Thanks for your thoughts everybody
I'm gonna go through some of the checks you've suggested and report back later today.
Jeff
Jeff
misfiring Honda Civic
- Thread starter greenjp
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First I'll answer all g20ooh's questions as best I can:
Not quite. It definitely smooths out once you get to 3,500, but at WOT it stumbled a bit, and when doing this is when the CEL started blinking again and is now back on solid. Couldn't get it to 3,500 in 5th safely - too fast for the roads I was on
It definitely seemed to run smooth for the first minute of operation. It also runs ok with very light throttle positions at any rpm.
Here's the sequence of events. New cap, rotor, spark plugs, and wires installed last fall. Everything ran fine. A couple weeks ago one of the plug wires started popping loose off the plug, resulting in poor running. They were el cheapo generics and I discovered that they were falling apart. I replaced them on Tuesday with the new NGK wires. Everything was good. On Thursday, the FP3000 showed up and I put in a double dose along with filling up the tank since the car hasn't had any sort of gas additive for a few months. On Friday I drove the car about 60 miles, then gave it an oil change. Drove the car some more on Friday and Saturday. My wife took the car out for a 180 mile drive on Sunday, and called me about 50 miles in complaining of the symptoms.
All this seemed to check out. I don't have a voltmeter (need to get one of those) but visually the cap, rotor, wires, and plugs looked ok. I torqued the plugs too.
I replaced the cap and rotor last fall - in the process 2 of the bolts holding the cap to the distributor housing sheared off inside the distributor. One of those apparently common things that nobody mentions when you're planning the job! The cap is now held on by a stainless steel worm drive hose clamp - it's rock solid and has been fine for months.
It was replaced a couple of years ago, at 105k.
O2 sensors look to run $150 or so, so I agree
. Not sure when the fuel filter was replaced. Probably at the 90k service. I'll put on a new one as it's probably a good time for it regardless.
The dude on the radio show I called this morning suggested the same thing - but I don't think the EX has an EGR valve! The Haynes manual indicates that only models with the D16Y5 engines have it - the EX is the D16Y8, and I couldn't find an EGR listed for the EX on any parts websites. If anyone knows otherwise, I'd love to be filled in.
I'll be the happiest guy around if a fuel filter fixes it!
I believe the cap, rotor, wires, and plugs are all ok - none of those of course preclude something like coils or the distributor itself.
jeff
Not quite. It definitely smooths out once you get to 3,500, but at WOT it stumbled a bit, and when doing this is when the CEL started blinking again and is now back on solid. Couldn't get it to 3,500 in 5th safely - too fast for the roads I was on
Here's the sequence of events. New cap, rotor, spark plugs, and wires installed last fall. Everything ran fine. A couple weeks ago one of the plug wires started popping loose off the plug, resulting in poor running. They were el cheapo generics and I discovered that they were falling apart. I replaced them on Tuesday with the new NGK wires. Everything was good. On Thursday, the FP3000 showed up and I put in a double dose along with filling up the tank since the car hasn't had any sort of gas additive for a few months. On Friday I drove the car about 60 miles, then gave it an oil change. Drove the car some more on Friday and Saturday. My wife took the car out for a 180 mile drive on Sunday, and called me about 50 miles in complaining of the symptoms.
All this seemed to check out. I don't have a voltmeter (need to get one of those) but visually the cap, rotor, wires, and plugs looked ok. I torqued the plugs too.
I replaced the cap and rotor last fall - in the process 2 of the bolts holding the cap to the distributor housing sheared off inside the distributor. One of those apparently common things that nobody mentions when you're planning the job! The cap is now held on by a stainless steel worm drive hose clamp - it's rock solid and has been fine for months.
It was replaced a couple of years ago, at 105k.
O2 sensors look to run $150 or so, so I agree
The dude on the radio show I called this morning suggested the same thing - but I don't think the EX has an EGR valve! The Haynes manual indicates that only models with the D16Y5 engines have it - the EX is the D16Y8, and I couldn't find an EGR listed for the EX on any parts websites. If anyone knows otherwise, I'd love to be filled in.
I'll be the happiest guy around if a fuel filter fixes it!
I believe the cap, rotor, wires, and plugs are all ok - none of those of course preclude something like coils or the distributor itself.
jeff
maybe the FP released varnish/junk and did clog the filter, that's what happened on my galant...thought she was having fuel delivery issues, etc etc....
Jeff ,
Good post that makes everything much clearer .
Wish I could say the same about what I posted - this is an attempt to say it better .Concepts make for shorter and better posts so some that matter follow .
We want to play and find under what circumstances we can induce/reduce or eliminate your miss . You have already developed much useful information here so we want to add to that and see how we can vary our results above that 3500-4000rpm . We also would like to know if possible that the engine will pull thru to 6000rpm in gear and if necc where it will and where it won't .There are many ways to do this and develop a profile of how your miss is "performing" above 3500 or even better in the 4000-6000rpm range .
So in conceptual terms you would vary your starting conditions ( vehicle speed in what gear before going to a higher gear/ fifth ( ie load ) and large/wot settings .
If you can , tip toe up what ever way makes sense in what ever gear to 3500RPM and then play with it in 5th from there .If that feels really bad try it in 4th , if it still feels bad try it in 3rd etc .You can work your way up or work your way down - either way is likely to be good .The reason to carefully try a 5th gear wot from say 2/3rd is that is the acid test in a sense for largely minimizing/eliminating some variables here ie you want to "get a load" on the engine at high/maxed throttle settings at different and esp higher rpm .If you are good here then you can rip thru the other combinations very quickly and less completely . (I am confident you know the difference between a misfire/no fire vs detonation/preignition and how to respond if you encounter the later).Short version -Misfire press on - anything else decrease the throttle/ load to eliminate but keep going "slower" if possible .If not , grab another gear and make note .
If there is a time constraint you can skip alot although possibly for a less useful effect later .Ideally we want all the combinations were it comes and goes or varies but by no means do we have to have them all .
It "sounds" like getting enough road to do this safely and sensibly maybe inconvenient so if neccessary/helpful we can get whats useful other ways such as using a hill etc .
As an example with a steep and long enough grade you could use 2 to 3 and then hit the throttle etc and get most of what we want here . I say most simply because modern engine control systems are very much gear dependent on what they decide to do but a big enough load with a big enough throttle setting for along enough period of time will largely minimize that effect .
Final thought just a maybe good to do or maybe a def. not needed .
In your mind is there any possibility that rotor could have moved ? Doesn't sound like it but I don't know how to picture this particular installation .Also when those screws gave you grief were you able to account for all the bits and pieces ? Thats interesting about the EGR - if correct "sounds' like they were clever enough to use strictly reversion .I "think" you can get that O2 sensor a little cheaper .
Finally again in a very bad WAG sort of way sounds more and more like fuel injectors (dirty not necc. shot ) , fuel pressure , fuel filter , etc rather than ignition as per Rob ,EDDIE , and chromes observation about EGR (effect) if you twist it a bit .Also "sounds" like its started to improve a bit which supports the previous .
Its the weekend and its spring so you just might want to screw the rest and throw a decent quality filter on there and see what happens .
In any case let us know what you find out .
I am assuming your throttle body is ok . If I was cruising by the right kind of parts store I might ask them to run a quick check on your battery and charging system - definitely just a third level nice to know at this point . Any chance of grabbing a vacuum gauge ? It can be phenomenally useful to run a long line to the cabin and have observation( informed second party ) while testing( not just at rest ) . Again not required just nice if easy .
Final thought - and I'm just thinking aloud here - keep in mind I'm lazy and crazy all at the same time but given my schedule I'd probably change the filter , throw in a decent fast acting injecter cleaner , top off the tank with some quality fuel and see what happens .Thats not a knock on the FP3000 and I would plan on continiuing on with it as you go . Maybe one of the FP people have a better or similiar idea .
Sorry for the way this rambles and needs editing I'm out of time .
Good post that makes everything much clearer .
Wish I could say the same about what I posted - this is an attempt to say it better .Concepts make for shorter and better posts so some that matter follow .
We want to play and find under what circumstances we can induce/reduce or eliminate your miss . You have already developed much useful information here so we want to add to that and see how we can vary our results above that 3500-4000rpm . We also would like to know if possible that the engine will pull thru to 6000rpm in gear and if necc where it will and where it won't .There are many ways to do this and develop a profile of how your miss is "performing" above 3500 or even better in the 4000-6000rpm range .
So in conceptual terms you would vary your starting conditions ( vehicle speed in what gear before going to a higher gear/ fifth ( ie load ) and large/wot settings .
If you can , tip toe up what ever way makes sense in what ever gear to 3500RPM and then play with it in 5th from there .If that feels really bad try it in 4th , if it still feels bad try it in 3rd etc .You can work your way up or work your way down - either way is likely to be good .The reason to carefully try a 5th gear wot from say 2/3rd is that is the acid test in a sense for largely minimizing/eliminating some variables here ie you want to "get a load" on the engine at high/maxed throttle settings at different and esp higher rpm .If you are good here then you can rip thru the other combinations very quickly and less completely . (I am confident you know the difference between a misfire/no fire vs detonation/preignition and how to respond if you encounter the later).Short version -Misfire press on - anything else decrease the throttle/ load to eliminate but keep going "slower" if possible .If not , grab another gear and make note .
If there is a time constraint you can skip alot although possibly for a less useful effect later .Ideally we want all the combinations were it comes and goes or varies but by no means do we have to have them all .
It "sounds" like getting enough road to do this safely and sensibly maybe inconvenient so if neccessary/helpful we can get whats useful other ways such as using a hill etc .
As an example with a steep and long enough grade you could use 2 to 3 and then hit the throttle etc and get most of what we want here . I say most simply because modern engine control systems are very much gear dependent on what they decide to do but a big enough load with a big enough throttle setting for along enough period of time will largely minimize that effect .
Final thought just a maybe good to do or maybe a def. not needed .
In your mind is there any possibility that rotor could have moved ? Doesn't sound like it but I don't know how to picture this particular installation .Also when those screws gave you grief were you able to account for all the bits and pieces ? Thats interesting about the EGR - if correct "sounds' like they were clever enough to use strictly reversion .I "think" you can get that O2 sensor a little cheaper .
Finally again in a very bad WAG sort of way sounds more and more like fuel injectors (dirty not necc. shot ) , fuel pressure , fuel filter , etc rather than ignition as per Rob ,EDDIE , and chromes observation about EGR (effect) if you twist it a bit .Also "sounds" like its started to improve a bit which supports the previous .
Its the weekend and its spring so you just might want to screw the rest and throw a decent quality filter on there and see what happens .
In any case let us know what you find out .
I am assuming your throttle body is ok . If I was cruising by the right kind of parts store I might ask them to run a quick check on your battery and charging system - definitely just a third level nice to know at this point . Any chance of grabbing a vacuum gauge ? It can be phenomenally useful to run a long line to the cabin and have observation( informed second party ) while testing( not just at rest ) . Again not required just nice if easy .
Final thought - and I'm just thinking aloud here - keep in mind I'm lazy and crazy all at the same time but given my schedule I'd probably change the filter , throw in a decent fast acting injecter cleaner , top off the tank with some quality fuel and see what happens .Thats not a knock on the FP3000 and I would plan on continiuing on with it as you go . Maybe one of the FP people have a better or similiar idea .
Sorry for the way this rambles and needs editing I'm out of time .
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Jeff,
Nothing more than things that run around in my head here - like to know stuff really .
1)Valve adjustment ? If required when done ?
2) VTEC operating parameters ? I know they are usually somewhat vague .
3) Since its so quick and easy .... take a look some pitch black evening while the engine is running and warm and observe if you can see or hear any arcing vv ignition .
Nothing more than things that run around in my head here - like to know stuff really .
1)Valve adjustment ? If required when done ?
2) VTEC operating parameters ? I know they are usually somewhat vague .
3) Since its so quick and easy .... take a look some pitch black evening while the engine is running and warm and observe if you can see or hear any arcing vv ignition .
g20ooh, thanks a ton for your help with this
I'll be driving the car for 180+ miles Sunday, mostly on lightly traveled highways so I should be able to play around. Maybe not 5th gear much past 4,500 rpms or so (don't want any reckless driving tickets
) but I should be able to do the rest.
The valve adjustment is a 90k service item, so it was done then. Not due again until 180k.
Not sure about the VTEC. I know it's a simple one step version, not sure at what rpms it switches.
That's a good thought on checking for arcing. I should be able to do that tomorrow night.
jeff
I'll be driving the car for 180+ miles Sunday, mostly on lightly traveled highways so I should be able to play around. Maybe not 5th gear much past 4,500 rpms or so (don't want any reckless driving tickets
The valve adjustment is a 90k service item, so it was done then. Not due again until 180k.
Not sure about the VTEC. I know it's a simple one step version, not sure at what rpms it switches.
That's a good thought on checking for arcing. I should be able to do that tomorrow night.
jeff
Ok, I'm home from my trip with some more observations.
First, when I started the car this morning the CEL was no longer on. Not sure what to make of that. The main thing that's really cooking my noodle is this - the car runs almost perfectly for the first few minutes in the morning. I got in, started it, and immediately started driving. It ran smooth & strong - no hesitation, no misfiring, in every gear, any rpms, heavy throttle. Probably got three minutes of that. After shorter stops, there will be a shorter period of good running, as little as 15-20 seconds. I'll check this again in the morning when I head to work.
The misfiring slowly came back then. My first good WOT test was from a standing start heading up a long, steep hill. This was 6 or 7 minutes into the drive, so the "normal" misfiring was back. I got into second quickly, it smoothed out after the 3,500 rpm point and ran strong up over 5k. But, the CEL came on around 4,500 - no blinking, it just lit up and stayed on the rest of the day. Into 3rd gear it kept running smoothly.
I then tested out a bunch at highway speeds (65+) in 3rd, 4th, and 5th gears. The misfiring is consistent under 3,500, if I dip into the throttle any more than a tiny bit the engine stumbles. Above 3,500, regardless of gear, it responds pretty well. However, at WOT it does occasionally misfire - it's not nearly as bad as at the lower rpms, but it's there.
So that's that. I've got a new fuel filter sitting in the garage, probably install that in a day or two.
Speaking of fast acting fuel system cleaners, ironically when I was on the phone with the radio guy (Pat Goss for those in the DC area) I said the "BG winning word" so I'll have a can of 44K showing up sometime soon.
jeff
First, when I started the car this morning the CEL was no longer on. Not sure what to make of that. The main thing that's really cooking my noodle is this - the car runs almost perfectly for the first few minutes in the morning. I got in, started it, and immediately started driving. It ran smooth & strong - no hesitation, no misfiring, in every gear, any rpms, heavy throttle. Probably got three minutes of that. After shorter stops, there will be a shorter period of good running, as little as 15-20 seconds. I'll check this again in the morning when I head to work.
The misfiring slowly came back then. My first good WOT test was from a standing start heading up a long, steep hill. This was 6 or 7 minutes into the drive, so the "normal" misfiring was back. I got into second quickly, it smoothed out after the 3,500 rpm point and ran strong up over 5k. But, the CEL came on around 4,500 - no blinking, it just lit up and stayed on the rest of the day. Into 3rd gear it kept running smoothly.
I then tested out a bunch at highway speeds (65+) in 3rd, 4th, and 5th gears. The misfiring is consistent under 3,500, if I dip into the throttle any more than a tiny bit the engine stumbles. Above 3,500, regardless of gear, it responds pretty well. However, at WOT it does occasionally misfire - it's not nearly as bad as at the lower rpms, but it's there.
So that's that. I've got a new fuel filter sitting in the garage, probably install that in a day or two.
Speaking of fast acting fuel system cleaners, ironically when I was on the phone with the radio guy (Pat Goss for those in the DC area) I said the "BG winning word" so I'll have a can of 44K showing up sometime soon.
jeff
Although I'm not as experienced as many on this site, i think it works better if it's installed on the car...
Jeff ,
Good stuff !
You got enough of the right kind of info that you can proceed with a lot more confidence !
Remember we don't have the big boy toys to do this really rightously but just by the seat of the computer I'd say its about 80/20 that your ignition is not the primary problem and working with what you got I'd just assume the rest for now .
So....lets review a useful oversimplification and see where it takes us .
In the real world to avoid a misfire/no fire we really only need 3-4 things . ( Do not confuse this with best,optimal, clean or oem intended "firing")
So we need some kind of compression ,some kind of useable fuel/air mix , and some kind of useable spark/ ( spark timing ) to avoid a misfire or really to avoid excessive misfiring which is what you really have here .
Well , although we haven't discussed it you obviously have compression , at least enough fuel volume to support 5000RPM IN 5TH with a fairly wide throttle opening and enough of a spark at good enough timing to fire that . (Your timing appears close enough at most/all times in general) . Don't forget all the codes you didn't trip either .
So ......waving our hands over all the yea buts and basically ignoring anything that gets in the way of our conclusion it really starts to look more and more to be an issue of the fuel/air charge being either inadequate in volume or improperly distributed/mixed or some combination of all three . In a practical sense it doesn't matter what combination it is ... for now but its at least a little more likely to be distribution ie dirty and /or leaky injector(s) .
Well , lets not get ahead of ourselves .
In general then .... that gets us back to the fuel/fuel air system , throttle body , vacuum leaks ,the non egr egr or some emissions control system component ie anything that would limit or messup the mix and or the AF distribution within a/ each cylinder .
Bottom line , although the injector - filter thing is looking very likely it don't forget the vacuum leak throttlebody - at least a quick visual to be sure .
LT's observation on the exhaust manifold could conceivably explain much of all this as well esp since this engine doesn't appear to have a conventional egr system .
FWIW that trip you took and the way you did your testing was probably a real good thing to have done to the car .
Let us know .
Good stuff !
You got enough of the right kind of info that you can proceed with a lot more confidence !
Remember we don't have the big boy toys to do this really rightously but just by the seat of the computer I'd say its about 80/20 that your ignition is not the primary problem and working with what you got I'd just assume the rest for now .
So....lets review a useful oversimplification and see where it takes us .
In the real world to avoid a misfire/no fire we really only need 3-4 things . ( Do not confuse this with best,optimal, clean or oem intended "firing")
So we need some kind of compression ,some kind of useable fuel/air mix , and some kind of useable spark/ ( spark timing ) to avoid a misfire or really to avoid excessive misfiring which is what you really have here .
Well , although we haven't discussed it you obviously have compression , at least enough fuel volume to support 5000RPM IN 5TH with a fairly wide throttle opening and enough of a spark at good enough timing to fire that . (Your timing appears close enough at most/all times in general) . Don't forget all the codes you didn't trip either .
So ......waving our hands over all the yea buts and basically ignoring anything that gets in the way of our conclusion it really starts to look more and more to be an issue of the fuel/air charge being either inadequate in volume or improperly distributed/mixed or some combination of all three . In a practical sense it doesn't matter what combination it is ... for now but its at least a little more likely to be distribution ie dirty and /or leaky injector(s) .
Well , lets not get ahead of ourselves .
In general then .... that gets us back to the fuel/fuel air system , throttle body , vacuum leaks ,the non egr egr or some emissions control system component ie anything that would limit or messup the mix and or the AF distribution within a/ each cylinder .
Bottom line , although the injector - filter thing is looking very likely it don't forget the vacuum leak throttlebody - at least a quick visual to be sure .
LT's observation on the exhaust manifold could conceivably explain much of all this as well esp since this engine doesn't appear to have a conventional egr system .
FWIW that trip you took and the way you did your testing was probably a real good thing to have done to the car .
Let us know .
I'm just wondering who's going to give me the $20.
like I said ...unplug the injectors one at a time..see if when you do...that one of them doesn't increase the misfire..that is the bad one ....
Wait a minute, you mean I've got to install the new filter
I plan on doing that tonight. I figure I'll do that one simple step before going deeper into fuel injectors or exhaust manifolds.
This morning the car once again drove perfectly for 2-3 minutes. Anybody got theories on why that would be?
As for fuel injectors - I'm asking because I'm trying to learn as much as I can in this process - if the miss is on all cylinders and predictable, but not ever-present, how would one bad injector be the source of the problem?
For inspecting the exhaust manifold - any special tricks? I know how to remove the heat shield (it's been a rattling nuisance in the past) anything to look for aside from obvious cracks?
jeff
I plan on doing that tonight. I figure I'll do that one simple step before going deeper into fuel injectors or exhaust manifolds.
This morning the car once again drove perfectly for 2-3 minutes. Anybody got theories on why that would be?
As for fuel injectors - I'm asking because I'm trying to learn as much as I can in this process - if the miss is on all cylinders and predictable, but not ever-present, how would one bad injector be the source of the problem?
For inspecting the exhaust manifold - any special tricks? I know how to remove the heat shield (it's been a rattling nuisance in the past) anything to look for aside from obvious cracks?
jeff
My galant had somewhat the same issues:
http://theoildrop.server101.com/forums/s...rekqc2daqe2ll3d
http://theoildrop.server101.com/forums/s...rekqc2daqe2ll3d
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Wait a minute, you mean I've got to install the new filterYes . Make sure its of decent quality as well . (Also keep Rob's experience in mind ) .BTW , what type of filter do you have on the vehicle now ? Just as importantlyyou need to get either an acceptable , effective fp3000 big jolt going again or better yet
something else for the injectors ( think synergistic effect ) and perhaps some/ all the other fuel system components we haven't discussed yet . ( fuel pump , fuel pressure regulator , etc ) .The reality of fuels systems is unfortunately that you have two filters - the "fuel filter" and everything else most esp the injectors .
I plan on doing that tonight. I figure I'll do that one simple step before going deeper into fuel injectors or exhaust manifolds. Its not perfect but if you look at ALL your info its the direction to go - as long as you understand the IMPORTANT likelyhood/usefulness for injector cleaning/cleaner . Keep in mind what all this is doing to things like your other O2 sensor and CATALYTIC CONVERTERS , etc .
This morning the car once again drove perfectly for 2-3 minutes. Anybody got theories on why that would be? TIME AND OR TEMP for sure . Could be many , many things . Given all the rest its probably fuel enrichment/emission control scheduling thats overcoming the problem(s) . Same type of logic for above 3500 rpm operation (PLUS VTEC ) etc , etc . Also could be an exhaust manifold leak opening up , coil or fuel pump or something else getting to temp . ,etc , ( the list is endless ) but again , considering everything else ...... and playing percentages ...
As for fuel injectors - I'm asking because I'm trying to learn as much as I can in this process - if the miss is on all cylinders and predictable, but not ever-present, how would one bad injector be the source of the problem? YEP . One very unlikely - two - possible but still .... You are thinking correctly . As other posters noted at the beginning more likely but NOTcertain to be a "central" or "systemwide" problem Think - all your codes including 1399 plus how it runs out ....
For inspecting the exhaust manifold - any special tricks? I know how to remove the heat shield (it's been a rattling nuisance in the past) anything to look for aside from obvious cracks? This is strictly a judgement call . If you can eliminate /determine this quickly with some kind of accuracy go for it - maybe .If its going to prevent you from getting that filter,more injector cleaner in and the TB /Vacuum leaks etc rechecked do it later . (Sometimes its useful to remove the shield and look at night for the little blue light ) . Do you have a Mechanics stethoscope ? Maybe some of the Honda people know the ins and outs of this particular installation/problem ie the best wheres and hows to save time
jeff
There are many many many scenarios that could fit here and all we are really doing is playing percentages . As an example of playing percentages and what can happen you can make decisions with perfect information on outcomes and probabilities and come out short . Say as an example you take the big side of a bet that is definitely a 100:1 shot and if its your unlucky day you lose .That doesn't mean your decision method was faulty . So some /much of what I'm suggesting here is based on having none of the proper equipment at hand and the desire to minimize your time "expense" with a high probability of error decision making process thats the best you have .
Now the really short version is this ;
Lets stop being a mechanic and lets just be a detective and develop a working hypothesis - just after the problem developed .
The last thing of note that changed on this vehicle and its environment was you did some work and later added the fp3000 .Adding any fuel product to any 7year old vehicle with 144K has some known/predictable risks and outcomes . One of this would be in gross terms moving material from various places to other places such as the filter and the injectors .Using that as a working hypothesis lets now consider your data/experience with the car since the problem developed . Short version : all of it is consistent with that hypothesis . Is it consistent with other explanations ? Yes - big time -and combinations as well .
We can rank them a little bit if you keep the big picture and all your data in mind . . Well , again simple version is that whatever went wrong happened soon after you worked on it and more accurately the fp went in so considering say an exhaust manifold leak as an alternative hypothesis do you think the manifold cracked or opened up enough to matter then or do you think a fuel system problem developed or something got disturbed ? ie taking your working hypothesis and considering the alternative hypothesis which is more likely ? That does not mean that could not have happened or a bunch of other things as well , but consider the timing of events .( Lets just put aside but not forget the possibilty of several things at once as well . )
Lets also back up a bit .
Gary Allan gave you a great example of how something after service gave a problem . The second/equally likely cause here is that something similiar could have happened . You have already greatly reduced ( not eliminated but very usefully reduced ) the likelyhood of many things but you could usefully still further "reduce" the odds against your working hypothesis by rechecking for anything that might have been "disturbed" (and then from vibration or heat etc gone caflooy ) during the last two times the vehicle was worked on such as a connector , wire , ground . and some sort of vacuum hose leak . Same/slightly different logic on the throttlebody . I don't rate any of this as likely because I have a feeling you have been doing this all along but you never know and its quick and easy to do and therefore to get a useful "increase" in your percentages .
Two things . Any chance you could get a vacuum gauge ? A useable quality gauge is inexpensive ( 10 - 30 $ ) and would not only be really useful here but would be down the road as well .
Does your manual discuss anything like a two speed or two stage fuel pump and or regulator ie variable fuel pressure under different operating parameters - such as VTEC operation etc ?
No criticism intended IN ANY WAY WHAT SO EVER but we are getting pretty close to paralysis by analysis here - esp when we think of the miles you have already driven ,your CAT. CONV. , your #2 O2 sensor , and possibly some other things such as your exhaust valves .
Not telling you what to do but its a prudent observation ; time to get going and get a positive change - to avoid some other stuff .
You know , the H*** with it . SINCE the fp3000 people haven't spoken up here and your time is valuable and you are waiting on the mail I'm going to suggest you get youself ( now ) some Injector Cleaner NOT all purpose - unless you can figure a double double dose of the FP3000 or something like that .
Just some to consider in no particular order - don't go cheap .
TECHRON , REDLINE's product , anything professional grade by 3M ,Valvoline Synpower ,RXP ,Gumout REGAINE and the others that work .It would be nice if somebody knows of an effective combination in this situation using the FP3000 AND something else .
I'm not listing everything possible or knocking anybodies product just to save time and controversy but stay off the lower end stuff .
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1) I'm putting g20ooh on retainer
2) Techron WAS on sale at AAP BOGO free, not sure if it still is.
2) Techron WAS on sale at AAP BOGO free, not sure if it still is.
2) Thats a good to know !
1) Well ,I 'm flattered but keep in mind if this one was mine I would consider this a perfect opportunity to experiment ( not cure - bandaid to buy time for good things to happen ) with all kinds of things ..... like Bosch Platinum +4s
Now where is it you want me to send that retainer back to ?
1) Well ,I 'm flattered but keep in mind if this one was mine I would consider this a perfect opportunity to experiment ( not cure - bandaid to buy time for good things to happen ) with all kinds of things ..... like Bosch Platinum +4s
Now where is it you want me to send that retainer back to ?
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