My Dad has a 1995 Lesabre with the 3800 and 185k miles on it. Being a 1995 it has that oddball OBD 1.5 computer that won't blink codes, but also can't be read by a normal scanner. So far I've replaced the plugs wires and all three coils, and after he drives it for 50 miles or so it will begin to run rough and miss. Runs perfectly when cool. Any ideas what I should try next? Should note that the Check Engine light does come on while its running poorly, then goes off when it is running right again.
95 Lesabre running rough when warm
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have you checked egr valve?
what does it take to get the codes out of this model?
what does it take to get the codes out of this model?
ok if you have seemed to try everything else to no avail. it could be a fuel injector i had this problem with a 1990 oldmobile with the 3.1 ...You can check the fuel injectors with an ohm meter..This oldsmobile ran like new until it got warm then ran very rough. These are known bad injectors..
When they got really bad the car would run perfect for a couple of miles then would stall and not start until it cooled off..
Very very common.
Also your best bet would be to buy the fuel injectors new.. Forget the so called rebuilt they are just cleaned and will NOT solve the problem..Been there done that...On another note call the injector perfector he was a lot of help.
When they got really bad the car would run perfect for a couple of miles then would stall and not start until it cooled off..
Very very common.
Also your best bet would be to buy the fuel injectors new.. Forget the so called rebuilt they are just cleaned and will NOT solve the problem..Been there done that...On another note call the injector perfector he was a lot of help.
Test the ohms at the injectors if they are all in spec then try the hunt and peck.
Just for the record i too replaced the ignition module to no avail thinking it may be a cold solder joint.
Just for the record i too replaced the ignition module to no avail thinking it may be a cold solder joint.
Originally Posted By: crazyoildude
Test the ohms at the injectors if they are all in spec then try the hunt and peck.
Just for the record i too replaced the ignition module to no avail thinking it may be a cold solder joint.
I have never heard of fuel injectors being one of those things that could have 'hot failure'. I can check that though, but would they test good when cold? I looked and this car does have different injectors than a 91, but I'm sure they are similar.
Only other things I could think of at the moment are Fuel filter, O2 sensor and perhaps the crankshaft position sensor.
I had thought about the Ignition module too, but they are pricey and I hate to replace it on a guess.
Test the ohms at the injectors if they are all in spec then try the hunt and peck.
Just for the record i too replaced the ignition module to no avail thinking it may be a cold solder joint.
I have never heard of fuel injectors being one of those things that could have 'hot failure'. I can check that though, but would they test good when cold? I looked and this car does have different injectors than a 91, but I'm sure they are similar.
Only other things I could think of at the moment are Fuel filter, O2 sensor and perhaps the crankshaft position sensor.
I had thought about the Ignition module too, but they are pricey and I hate to replace it on a guess.
If anyone knows how to/where I could get something to scan a 1995 computer that would also be helpful.
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Originally Posted By: BigD1
Ignition module could cause that too because it could be malfunctioning when it heats up under the hood, and run just fine when the module is cold.
My 87 Trofeo would do this,except once hot it would completely die,and I'd have to pull over and wait for it to cool off,then it'd run perfect till warmed up again. Lesson learned,use OEM parts only. The [censored] aftermarket (Chief Auto Parts,Wells brand) ignition module was a piece of junk. If that's the prob with your dad's Buick,replace with an AC Delco unit only.
Ignition module could cause that too because it could be malfunctioning when it heats up under the hood, and run just fine when the module is cold.
My 87 Trofeo would do this,except once hot it would completely die,and I'd have to pull over and wait for it to cool off,then it'd run perfect till warmed up again. Lesson learned,use OEM parts only. The [censored] aftermarket (Chief Auto Parts,Wells brand) ignition module was a piece of junk. If that's the prob with your dad's Buick,replace with an AC Delco unit only.
crazyoildude's method is what I would do.
Just looked over my GM manual flow charts. Change the fuel filter first. Let the engine sit there and idle with the hood closed, and when it starts to misfire cut the engine off. Pull all the injector connectors, and then use tester to see if the signal is going to the injectors. If the injector is not getting the signal, then you know it could possibly be an ignition module with a bad cold solder joint. If it is getting the signal to all the injectors, then it could be a bad injector.
Also, about the O2 sensor. My manual says that if the sensor goes bad the engine will start running rich, and in turn the computer will compensate to lean it out which causes not enough fuel going to the engine.
Just looked over my GM manual flow charts. Change the fuel filter first. Let the engine sit there and idle with the hood closed, and when it starts to misfire cut the engine off. Pull all the injector connectors, and then use tester to see if the signal is going to the injectors. If the injector is not getting the signal, then you know it could possibly be an ignition module with a bad cold solder joint. If it is getting the signal to all the injectors, then it could be a bad injector.
Also, about the O2 sensor. My manual says that if the sensor goes bad the engine will start running rich, and in turn the computer will compensate to lean it out which causes not enough fuel going to the engine.
This engine has GM Multec which are a real problem, 50% fail on the bench. Taking the Ohms is no good other than to tell you if has a open or short but the real test is the inductance measurement, the amount of mA the injector is drawing from the fuel injector driver. Many times the Ohms are fine and the current draw is way off.
What you need is a replacement that is a more modern design with an old EV1 plug. PM me if your interested i have access to new ones that are Gen III with EV1 in the correct length and flow with a better spray pattern so no adapters are needed, plug and play.
What you need is a replacement that is a more modern design with an old EV1 plug. PM me if your interested i have access to new ones that are Gen III with EV1 in the correct length and flow with a better spray pattern so no adapters are needed, plug and play.
@Trav
So you are saying the injector/injectors are over heating causing them to malfunction when they get hot, at least that's what I think you mean?
Are the Gen III Bosch injectors? If so, would a reconditioned set of those be a safe bet to use instead of spending a bundle on new?
So you are saying the injector/injectors are over heating causing them to malfunction when they get hot, at least that's what I think you mean?
Are the Gen III Bosch injectors? If so, would a reconditioned set of those be a safe bet to use instead of spending a bundle on new?
Exactly, when they get hot they could be failing, I cant say for sure what they are doing unless i had them on my machine but its common with these injectors.
I can get good low mile, wet cores and redo them, they work fine.
I can get good low mile, wet cores and redo them, they work fine.
I emailed tech support at Actron and they told me the CP9185 scanner should be able to read the codes on the car, so I'm going to give that a shot. If anyone else wants a fairly fancy scanner that does OBD I and OBD II there is a company that has them on ebay for around $40 shipped ($130 on amazon)
Since you are working on that Buick come on over to www.w-body.com/ and hang out. Lots of information over there.
Which years was the Buick LeSabre a W body ?
Originally Posted By: BigD1
Ebay link please.
On the Actron you mentioned, the chart at Amazon says that it needs the optional cables.
I'm at work so I can't get on ebay but this is the model:
https://actron.com/content/elite-autoscanner-trilingual-obd-ii-enhanced-and-can-optional-obd-i
If you have the OBD II style plug you can read it with no additional cables according to tech support and the reviews I read. If you have the older OBD I connector you will need an additional cable that is $10 on amazon. Also noticed this on Actron's website:
https://actron.com/content/autoxray-codescout-2500-bilingual-obd-i-and-obd-ii-code-reader
Comes with all the OBD I cables EXCEPT the one you need for a 95 GM, which is an extra $40.
Ebay link please.
On the Actron you mentioned, the chart at Amazon says that it needs the optional cables.
I'm at work so I can't get on ebay but this is the model:
https://actron.com/content/elite-autoscanner-trilingual-obd-ii-enhanced-and-can-optional-obd-i
If you have the OBD II style plug you can read it with no additional cables according to tech support and the reviews I read. If you have the older OBD I connector you will need an additional cable that is $10 on amazon. Also noticed this on Actron's website:
https://actron.com/content/autoxray-codescout-2500-bilingual-obd-i-and-obd-ii-code-reader
Comes with all the OBD I cables EXCEPT the one you need for a 95 GM, which is an extra $40.
Originally Posted By: Merkava_4
Which years was the Buick LeSabre a W body ?
Never said it was. Similar engines, and there's a lot of information about those engines. Even OBD swaps to OBD 2. Use it or don't. Don't matter to me. If you take a look under Power Train, http://60degreev6.com/ is a sub forum now of w-body too.
Which years was the Buick LeSabre a W body ?
Never said it was. Similar engines, and there's a lot of information about those engines. Even OBD swaps to OBD 2. Use it or don't. Don't matter to me. If you take a look under Power Train, http://60degreev6.com/ is a sub forum now of w-body too.
Just wanted to update. I replaced the O2 sensor the fuel filter and cleaned the MAF sensor and that seems to have fixed it. Thanks for all the responses
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