It's just for trying to raise the fuel pressure and enrichen the mixture. It won't harm anything since the fuel pressure regulator will only increase pressure a little. See if it improves the symptoms you are having. If so then that would point to probably the injectors being restrictive.
Another Respected Tech Tosses In The Towel!
- Thread starter demarpaint
- Start date
- Status
Sorry Vikas, its a 1988, I have the scanner for it for many years. No codes. In fact nothing showed with the Ford Break Out box either, or any diagnostics the techs ran on it. This is truly a project for an ace trouble shooter, I kid you not! Now these tech could be handing me a line of B_S too, but I've gone over it myself the best a DIY guy can do. I can't dix it either!
I just can't seem to find that Ace Tech. OTOH it makes me feel good since I basically confirmed all their findings before I took it in. Not that does me one bit of good!
I want to be 100% certain it is the injectors before I pull the trigger on that. The cost is high if its not them.
I have a list of questions for later when I talk with him again, top on the list is the CYL balance test.
I just can't seem to find that Ace Tech. OTOH it makes me feel good since I basically confirmed all their findings before I took it in. Not that does me one bit of good!
I want to be 100% certain it is the injectors before I pull the trigger on that. The cost is high if its not them.
I have a list of questions for later when I talk with him again, top on the list is the CYL balance test.
Originally Posted By: mechanicx
It's just for trying to raise the fuel pressure and enrichen the mixture. It won't harm anything since the fuel pressure regulator will only increase pressure a little. See if it improves the symptoms you are having. If so then that would point to probably the injectors being restrictive.
Can I plug up that vacuum line and drive it for a day or so? See how the hot restart is, and if it has a bit more power when cold? That sounds like a pretty basic thing, I'd be surprised these guys missed it. Certainly worth a shot, and extremely easy to do.
Any chance of a massive dose of FI cleaner cleaning it up with that regulator disconnected with the increased pressure? I'm tossing thoughts out here! Thanks
It's just for trying to raise the fuel pressure and enrichen the mixture. It won't harm anything since the fuel pressure regulator will only increase pressure a little. See if it improves the symptoms you are having. If so then that would point to probably the injectors being restrictive.
Can I plug up that vacuum line and drive it for a day or so? See how the hot restart is, and if it has a bit more power when cold? That sounds like a pretty basic thing, I'd be surprised these guys missed it. Certainly worth a shot, and extremely easy to do.
Any chance of a massive dose of FI cleaner cleaning it up with that regulator disconnected with the increased pressure? I'm tossing thoughts out here! Thanks
I think it would be OK to run it for a day. But just see how it runs with it disconnected first. I don't think it will run too rich. I think another dose of FI cleaner would be good to try. Don't mean to knock your vehicle at all but I dislike EEC-IV's diagnostics and yours isn't the only one that has had a mysterious/unsolvable stumble. I hope Overk1ll doesn't read that.
I love the van, or would have pulled the plug on it. On the open road it runs like a top, it is in fantastic condition both body and paint and turns heads when I wash and wax it. I do agree with you about the EEC-IV diagnostics, it is not user friendly when it comes to resolving this kind of issue Even Ford couldn't solve it with thier tools and techs.
I like Ford Vans and I like the 300 L6. I even prefer it for the most part to the Chevy/GMC van. EEC-IV might be OK if you have all the expenisive equipment, but it's still confusing. I think GM's OBD1 and even Chrysler's was better, more user friendly JMO. I figure unhooking the FPR wpould be a simple way to see if more fuel pressure helps the symptoms. Hope it helps.
Is the gas tank suppose to pressurize on this model?
- Joined
- Sep 28, 2002
- Messages
- 39,799
two things that I don't think (I may have missed it) have been mentioned. Is it EGR equipped? If so, it could be not seating properly. Check by drawing on the vacuum line to the diaphragm. If the idle goes bonkers ..it's good.
2nd, the battery. I had an off idle hesitation on my mother's Corsica for years. Just figured it was a characteristic (the liability of having gaps in new car purchases over the peaks and valleys of life). One day I just charged the battery for no good darn reason when I had it at work for a long weekend. The hestitation went away for a day or two.
The battery gave no trouble. No slow cranking ..no going dead. It was this way for YEARS. Come to find out ..just one cell was low and it could never reach full charge as far as the alternator's Zener's were concerned ..the alt was dragging heavy on the belt 24/7/365.
Just sweeping out my obscure corners of oddities in discovery.
2nd, the battery. I had an off idle hesitation on my mother's Corsica for years. Just figured it was a characteristic (the liability of having gaps in new car purchases over the peaks and valleys of life). One day I just charged the battery for no good darn reason when I had it at work for a long weekend. The hestitation went away for a day or two.
The battery gave no trouble. No slow cranking ..no going dead. It was this way for YEARS. Come to find out ..just one cell was low and it could never reach full charge as far as the alternator's Zener's were concerned ..the alt was dragging heavy on the belt 24/7/365.
Just sweeping out my obscure corners of oddities in discovery.
Originally Posted By: Eric Smith
Is the gas tank suppose to pressurize on this model?
No. As a side note it has dual tanks, and the problem is the same with both tanks.
Originally Posted By: Gary Allan
two things that I don't think (I may have missed it) have been mentioned. Is it EGR equipped? If so, it could be not seating properly. Check by drawing on the vacuum line to the diaphragm. If the idle goes bonkers ..it's good.
2nd, the battery. I had an off idle hesitation on my mother's Corsica for years. Just figured it was a characteristic (the liability of having gaps in new car purchases over the peaks and valleys of life). One day I just charged the battery for no good darn reason when I had it at work for a long weekend. The hestitation went away for a day or two.
The battery gave no trouble. No slow cranking ..no going dead. It was this way for YEARS. Come to find out ..just one cell was low and it could never reach full charge as far as the alternator's Zener's were concerned ..the alt was dragging heavy on the belt 24/7/365.
Just sweeping out my obscure corners of oddities in discovery.
The EGR is a Ford genuine replacement part about two years old, and was checked. I had a heck of a time locating one that was a FMC part. Aftermarket was easy to get. I might have forgotten to mention that.
That's interesting, I would have never thought of that. I have no problems with the battery, but I'm embarrassed to say the battery was last replaced 10/8/00, its having a birthday this week.
I don't tire easily or quit, but this has got me and a lot of others puzzled.
Is the gas tank suppose to pressurize on this model?
No. As a side note it has dual tanks, and the problem is the same with both tanks.
Originally Posted By: Gary Allan
two things that I don't think (I may have missed it) have been mentioned. Is it EGR equipped? If so, it could be not seating properly. Check by drawing on the vacuum line to the diaphragm. If the idle goes bonkers ..it's good.
2nd, the battery. I had an off idle hesitation on my mother's Corsica for years. Just figured it was a characteristic (the liability of having gaps in new car purchases over the peaks and valleys of life). One day I just charged the battery for no good darn reason when I had it at work for a long weekend. The hestitation went away for a day or two.
The battery gave no trouble. No slow cranking ..no going dead. It was this way for YEARS. Come to find out ..just one cell was low and it could never reach full charge as far as the alternator's Zener's were concerned ..the alt was dragging heavy on the belt 24/7/365.
Just sweeping out my obscure corners of oddities in discovery.
The EGR is a Ford genuine replacement part about two years old, and was checked. I had a heck of a time locating one that was a FMC part. Aftermarket was easy to get. I might have forgotten to mention that.
That's interesting, I would have never thought of that. I have no problems with the battery, but I'm embarrassed to say the battery was last replaced 10/8/00, its having a birthday this week.
I don't tire easily or quit, but this has got me and a lot of others puzzled.
They claimed all electrical connections and grounds were good and corrosion free. I have to take their word for it, it is something I didn't check.
Not as much as you'd think. All told about $400 over 2 years. The ECU was returned, as was the IAC, TPS, and several other hunches we had. The van is in mint condition, and I don't like the newer style Econoline Vans. This one is a hobby and a labor of love. Most Bitoger's would understand that.
Interesting you mention cost, in another thread of mine guys are telling me to replace an oil pan on a vehicle with over 120,000 more miles on it, and a beater. In that case I opted for a half arsed repair, and if it doesn't work I'll get rid of the vehicle. Different animal here, and different strokes for different folks.
Many of the parts changed were given to me from a buddy who owned an Econoline and they were NIB, other parts were wholesale.
Interesting you mention cost, in another thread of mine guys are telling me to replace an oil pan on a vehicle with over 120,000 more miles on it, and a beater. In that case I opted for a half arsed repair, and if it doesn't work I'll get rid of the vehicle. Different animal here, and different strokes for different folks.
Many of the parts changed were given to me from a buddy who owned an Econoline and they were NIB, other parts were wholesale.
That's got about 3,000 miles on it a Motorcraft part. All the plumbing is clean as well. I forgot to mention it in the list of what was checked and done.
Here's a quote from the 1988 OM, I guess Ford really wanted these changed out at 60K. Mine's been done every 35K.
Quote: NO COST PCV VALVE REPLACMENT.
The PCV valve on light trucks equipped with a 4.9L, 5.0L, 5.8L and 7.5L engine is a critical emission component. Your dealer will replace the valve at no cost at 60,000 miles/96,000 KM (except California and Canada).
I guess they didn't cause problems in Canada or California, or weren't used. LOL
Here's a quote from the 1988 OM, I guess Ford really wanted these changed out at 60K. Mine's been done every 35K.
Quote: NO COST PCV VALVE REPLACMENT.
The PCV valve on light trucks equipped with a 4.9L, 5.0L, 5.8L and 7.5L engine is a critical emission component. Your dealer will replace the valve at no cost at 60,000 miles/96,000 KM (except California and Canada).
I guess they didn't cause problems in Canada or California, or weren't used. LOL
Random Rants:
It is a cardinal sin to ever touch/adjust the idle hard stop on a Ford throttle body. That was the whole reason Ford came out with the IAC spacer/air bypass kit. Too bad it sludged up faster than a throttlebody rendering it useless.
If it were mine, I would reset the hard idle (IAC unplugged/warm engine) to spec, hook everything back up and reset the idle strategy correctly to eliminate that as a cause.
Pull the air temp sensor (I think it is in one of the intake runners #1?) and see if it is tarred up.
Hard to diag without the correct scanners/equipment to check it. If it is an early model (pre 91) then you need a shop with a 60 pin harness to tap into the PCM to get readings.
It is a cardinal sin to ever touch/adjust the idle hard stop on a Ford throttle body. That was the whole reason Ford came out with the IAC spacer/air bypass kit. Too bad it sludged up faster than a throttlebody rendering it useless.
If it were mine, I would reset the hard idle (IAC unplugged/warm engine) to spec, hook everything back up and reset the idle strategy correctly to eliminate that as a cause.
Pull the air temp sensor (I think it is in one of the intake runners #1?) and see if it is tarred up.
Hard to diag without the correct scanners/equipment to check it. If it is an early model (pre 91) then you need a shop with a 60 pin harness to tap into the PCM to get readings.
OVERKILL
$100 Site Donor 2021
Originally Posted By: mechanicx
I think it would be OK to run it for a day. But just see how it runs with it disconnected first. I don't think it will run too rich. I think another dose of FI cleaner would be good to try. Don't mean to knock your vehicle at all but I dislike EEC-IV's diagnostics and yours isn't the only one that has had a mysterious/unsolvable stumble. I hope Overk1ll doesn't read that.
Oh, I'm not going to dig you for that one, I agree. Diagnosing EEC-IV can be an absolute nightmare. It was very advanced for its day, but there was not much in the way of a good "interface" to provide a means of being able to view the feedback from all that "advanced" stuff.
I had a bad ground in a main harness that caused all kinds of weird issues. It wasn't a ground to the block or body, it was one of the "sensed" ECM grounds. Ended up splicing in a wire to the engine as a troubleshooting measure just out of pure frustration, and low and behold it fixed it! LOL!
BTW, your suggestion about spiking the fuel pressure is an excellent one. I've used it for testing for lean conditions on EEC-IV before.
This is very common (surge) with EEC-IV and sometimes very hard to get rid of. It usually happens due to a (sometimes perceived) lean or rich condition that the ECM is trying to compensate for. This causes the idle to "swing". VERY common on modified cars that don't have a chip-style tune on them.
The Lincoln surges like crazy if the battery is out of it and resets the ECM. Takes quite a while for it to be "right" again. This is due to it being modified (heads, cam, intake) and still running the stock ECM tune.
I think it would be OK to run it for a day. But just see how it runs with it disconnected first. I don't think it will run too rich. I think another dose of FI cleaner would be good to try. Don't mean to knock your vehicle at all but I dislike EEC-IV's diagnostics and yours isn't the only one that has had a mysterious/unsolvable stumble. I hope Overk1ll doesn't read that.
Oh, I'm not going to dig you for that one, I agree. Diagnosing EEC-IV can be an absolute nightmare. It was very advanced for its day, but there was not much in the way of a good "interface" to provide a means of being able to view the feedback from all that "advanced" stuff.
I had a bad ground in a main harness that caused all kinds of weird issues. It wasn't a ground to the block or body, it was one of the "sensed" ECM grounds. Ended up splicing in a wire to the engine as a troubleshooting measure just out of pure frustration, and low and behold it fixed it! LOL!
BTW, your suggestion about spiking the fuel pressure is an excellent one. I've used it for testing for lean conditions on EEC-IV before.
This is very common (surge) with EEC-IV and sometimes very hard to get rid of. It usually happens due to a (sometimes perceived) lean or rich condition that the ECM is trying to compensate for. This causes the idle to "swing". VERY common on modified cars that don't have a chip-style tune on them.
The Lincoln surges like crazy if the battery is out of it and resets the ECM. Takes quite a while for it to be "right" again. This is due to it being modified (heads, cam, intake) and still running the stock ECM tune.
Originally Posted By: punisher
Random Rants:
It is a cardinal sin to ever touch/adjust the idle hard stop on a Ford throttle body. That was the whole reason Ford came out with the IAC spacer/air bypass kit. Too bad it sludged up faster than a throttlebody rendering it useless.
If it were mine, I would reset the hard idle (IAC unplugged/warm engine) to spec, hook everything back up and reset the idle strategy correctly to eliminate that as a cause.
Pull the air temp sensor (I think it is in one of the intake runners #1?) and see if it is tarred up.
Hard to diag without the correct scanners/equipment to check it. If it is an early model (pre 91) then you need a shop with a 60 pin harness to tap into the PCM to get readings.
Punisher we tried with and without the spacer plate the symptoms are exactly the same. Even with different IAC valves installed. I allowed it to relearn the idle strategy, which takes a bit of time. In fact each time I changed a part I disconnected the battery.
Two of the first parts replaced early on in this PITA saga were the CTS and Air Temp Sensor which is in one of the runners. Those to me measured temperature and were logical choices after vacuum leaks were first to de ruled out. The Air Charge Sensor was actually pretty clean, but it was a PITA to get out so I replaced it. I felt there was not point in using the old part over again in that instance. I've tossed quite a few parts at this thing.
Originally Posted By: OVERK1LL
BTW, your suggestion about spiking the fuel pressure is an excellent one. I've used it for testing for lean conditions on EEC-IV before.
This is very common (surge) with EEC-IV and sometimes very hard to get rid of. It usually happens due to a (sometimes perceived) lean or rich condition that the ECM is trying to compensate for. This causes the idle to "swing". VERY common on modified cars that don't have a chip-style tune on them.
The Lincoln surges like crazy if the battery is out of it and resets the ECM. Takes quite a while for it to be "right" again. This is due to it being modified (heads, cam, intake) and still running the stock ECM tune.
I like the FP regulator idea myself and plan on doing it. I'm going to hit it with two bottles of Red Line FI cleaner in the rear tank which is the bigger of the two IIRC it holds about 22 gallons of gas the front tank holds about 18 gallons, and see if that does anything.
Surges like crazy on a hot restart pretty much sums it up OVERK1LL. One tap of the gas pedal fixes it. Although today it seemed better, the only thing new is the throttle body gasket. Ford had some kind of upgrade to it.
Once the engine is warmed up it alway ran a little better in the colder weather than the hot weather. Slight but enough to notice.
Again thanks for the interest and help!
Random Rants:
It is a cardinal sin to ever touch/adjust the idle hard stop on a Ford throttle body. That was the whole reason Ford came out with the IAC spacer/air bypass kit. Too bad it sludged up faster than a throttlebody rendering it useless.
If it were mine, I would reset the hard idle (IAC unplugged/warm engine) to spec, hook everything back up and reset the idle strategy correctly to eliminate that as a cause.
Pull the air temp sensor (I think it is in one of the intake runners #1?) and see if it is tarred up.
Hard to diag without the correct scanners/equipment to check it. If it is an early model (pre 91) then you need a shop with a 60 pin harness to tap into the PCM to get readings.
Punisher we tried with and without the spacer plate the symptoms are exactly the same. Even with different IAC valves installed. I allowed it to relearn the idle strategy, which takes a bit of time. In fact each time I changed a part I disconnected the battery.
Two of the first parts replaced early on in this PITA saga were the CTS and Air Temp Sensor which is in one of the runners. Those to me measured temperature and were logical choices after vacuum leaks were first to de ruled out. The Air Charge Sensor was actually pretty clean, but it was a PITA to get out so I replaced it. I felt there was not point in using the old part over again in that instance. I've tossed quite a few parts at this thing.
Originally Posted By: OVERK1LL
BTW, your suggestion about spiking the fuel pressure is an excellent one. I've used it for testing for lean conditions on EEC-IV before.
This is very common (surge) with EEC-IV and sometimes very hard to get rid of. It usually happens due to a (sometimes perceived) lean or rich condition that the ECM is trying to compensate for. This causes the idle to "swing". VERY common on modified cars that don't have a chip-style tune on them.
The Lincoln surges like crazy if the battery is out of it and resets the ECM. Takes quite a while for it to be "right" again. This is due to it being modified (heads, cam, intake) and still running the stock ECM tune.
I like the FP regulator idea myself and plan on doing it. I'm going to hit it with two bottles of Red Line FI cleaner in the rear tank which is the bigger of the two IIRC it holds about 22 gallons of gas the front tank holds about 18 gallons, and see if that does anything.
Surges like crazy on a hot restart pretty much sums it up OVERK1LL. One tap of the gas pedal fixes it. Although today it seemed better, the only thing new is the throttle body gasket. Ford had some kind of upgrade to it.
Once the engine is warmed up it alway ran a little better in the colder weather than the hot weather. Slight but enough to notice.
Again thanks for the interest and help!
Originally Posted By: onion
What year is this van? What engine?
Great question! I can't believe I didn't put that in the very top post. I'm slipping.
1988 E-150 4.9L 73,000 miles.
What year is this van? What engine?
Great question! I can't believe I didn't put that in the very top post. I'm slipping.
1988 E-150 4.9L 73,000 miles.
- Status
Similar threads
