2002 Lesabre randomly shuts off while driving - no codes (to cause this)

[dadymurano]

Possible cracked porcelain on plug number 6 or the spark plug wire may be arcing out to the O2 sensor cable.

As stated above, during my work on the car i got an occasional po306. Moved the coilpak down and randomly got a po304. Purchased a lifetime delco coil and havent had any more po30x misfires. The coilpack that whet bad was a replacement i purchased off amazon for cheap, with a 1 year warranty. That's about how long it lasted.
Now i don't believe that has been my issue, just a random occurance that can happen.

I took off the egr block spacer. Get the po401 each time i drive it along with hesitation as i give it gas sometimes. Not all the time. I also can hear a pinging from the engine when under load sometimes.

I have ordered a EGR valve. As stated above I took off the throttle body to make sure all was clean with the exhaust tube that comes up into the intake manifold. Very clean.

Not sure if i posted it or not but I've been marking some of the MAF sensors that are obviously not up to par. 1 cheap replacement that was purchased form a company off of amazon

	WCTFBA1002 Manufacturer ‏ : ‎ YCT ASIN ‏ : ‎ B08LCV6Z9B

causes the car to not start when installed. 1 of the used MAF sensors I got from pullapart caused a code p0101, basically said the airflow didnt corespond to what was expected with the throttle at that position..so I marked it and replaced it with another that seems to agree with the car. It also came off a 2002 - 2004 lesabre 3.8 from pullapart. Each of the last two were original GM.

I may use my laptop again to look at more pid info. If it comes to taking it to a professional for a quality diagnosis I will. I'm really curious what has caused my Lesabre to become so troublesome. I can still drive it now without the shutting off at random times, but I feel like I've accomplished very little of what started out as a thread to help someone with a similar problem.

(ps- the S-10 with the worn gears on the distributor rus as good as it has in years. So i got that going for me) 😊

 

[BuickGirlFromMars]

As stated above, during my work on the car i got an occasional po306. Moved the coilpak down and randomly got a po304. Purchased a lifetime delco coil and havent had any more po30x misfires. The coilpack that whet bad was a replacement i purchased off amazon for cheap, with a 1 year warranty. That's about how long it lasted.
Now i don't believe that has been my issue, just a random occurance that can happen.

I took off the egr block spacer. Get the po401 each time i drive it along with hesitation as i give it gas sometimes. Not all the time. I also can hear a pinging from the engine when under load sometimes.

I have ordered a EGR valve. As stated above I took off the throttle body to make sure all was clean with the exhaust tube that comes up into the intake manifold. Very clean.

Not sure if i posted it or not but I've been marking some of the MAF sensors that are obviously not up to par. 1 cheap replacement that was purchased form a company off of amazon

	WCTFBA1002 Manufacturer ‏ : ‎ YCT ASIN ‏ : ‎ B08LCV6Z9B

causes the car to not start when installed. 1 of the used MAF sensors I got from pullapart caused a code p0101, basically said the airflow didnt corespond to what was expected with the throttle at that position..so I marked it and replaced it with another that seems to agree with the car. It also came off a 2002 - 2004 lesabre 3.8 from pullapart. Each of the last two were original GM.

I may use my laptop again to look at more pid info. If it comes to taking it to a professional for a quality diagnosis I will. I'm really curious what has caused my Lesabre to become so troublesome. I can still drive it now without the shutting off at random times, but I feel like I've accomplished very little of what started out as a thread to help someone with a similar problem.

(ps- the S-10 with the worn gears on the distributor rus as good as it has in years. So i got that going for me) 😊

EGR cant work right if your MAF Isnt working right. Likewise, if these changes arent including a battery reconnect your possibly confusing the hell out of the PCM especially if normal working voltages or ranges happen to shift and it was assuming a "norma;" value(some things work like this)


Also, the MAFs, were they cleaned?

 

[dadymurano]

Thanks for the response, and very good advice. I did disconnect the battery for a while and charged it a few hrs due to not driving it very much. Keep MAF cleaner on hand.

My ex-wife just had her battery go dead on her new Nissan due to lack of driving and walking past it several time a day with the key fob waiking up the car. I got her a small battery tender and showed her how to use it.

The EGR valve was supposed to be delivered yesterday, but it now says today or tomorrow. I'm off until wed. due to meeting with my accountant and too much paperwork. Damn I hate taxes.

 

[BuickGirlFromMars]

Thanks for the response, and very good advice. I did disconnect the battery for a while and charged it a few hrs due to not driving it very much. Keep MAF cleaner on hand.

My ex-wife just had her battery go dead on her new Nissan due to lack of driving and walking past it several time a day with the key fob waiking up the car. I got her a small battery tender and showed her how to use it.

The EGR valve was supposed to be delivered yesterday, but it now says today or tomorrow. I'm off until wed. due to meeting with my accountant and too much paperwork. Damn I hate taxes.

Cant tax someone who "lights their fire" wink wink

 

[2007LucerneCXL]

Light on fire, deductible

 

[mro1974]

I agree about the chineese knockoff parts. Problem is, that is where your name brand AC Delco parts are manufactured. I go to pull-a-part and get a few simple parts on occasion for test purposes.

I once took got a master cylinder and vacuum booster off an old '81 nissan to put on my 78 datsun after over 4 or 5 bad rebuilds out of the box from Napa and Auto Zone. The junkyard part works like a champ. Still does.

OK- so today I went to crank the LeSabre. It would almost start but never did. I unplugged the MAF, screwed on my fuel gauge. ( thanks to GM/Buick for putting a shrader valve on the fuel rail.) Turned the ignition far enough to hear the fuel pump come on. Got out and looked at the fuel gauge. 50psi. Got in the car and tried to start it with the MAF unplugged. Same result. Unplugged every sensor on the intake. (A normal running car will start up even with the EVAP, TPS, MAF, EGR all unplugged. Same issue NO start. Plugged everything back and read the codes. Obviously I had a code for each pid I unplugged. Cleared my codes. Kept trying to start it, as it usually will finally start but run very poor. Finally started. No throttle adjustment feathering the pedal to make it rev or idle. Was able to keep it running for a minute, but running very poor as I feathered the gas pedal. Then like majic it went back to normal idle, running fine. Read the codes. None.
I have a new Crank and Cam sensor. I'm gonna replace them and see what happens. Probably do it tonight if I don't drink too much.


While I'm just your average back yard mechanic, I've been able to fix every car/truck i set my mind to fix. Got my laptop on charge upstairs so I can see a large screen of certain pids i want to monitor while it's running, but may not use it until I replace the crank and cam sensor. - still no code indicating either is defective-

If it turns out to be a clogged cat I'm gonna be angry. (Exhaust flows vey well) But I've installed test pipes before. The frustrating part is no codes. Usually if you have no electronic codes look for lean or rich fuel trims, but even that doesnt usually shut off the engine with no start.

OK gettin off track a little bit.

I had a 98 Lesabre & a 2004 Lesabre. One would not start at all & the other one started but ran rough. Neither one threw a code. The ICM was bad on both of them. Replaced ICM on both & they ran fine. Just a thought.

 

[mro1974]

It seems that GM has stuck with .060 plug gap ever since the HEI from the 70s

GM HEI came out in 1975. I worked for a GM shop & we would bang the spark plug gap down to .045 when we changed plugs. I believe there was a GM service bulletin stating intermittent problems with the early HEI's spark jumping a gap of .060.

 

[dadymurano]

Light on fire, deductible
View attachment 36592

My 1st car was a 1978 buick regal sports coup with 3.8 turbo. Darker than sky blue but very nice color. Bleach white interior. Blue carpet. Automatic with consol shifter. I loved that car.

 

[dadymurano]

OK so when i moved the top coil pack down the p0306 changed to p0304? Which as Mrs Martian pointed out that coil pack doesnt control plug 4. So with two new delco lifetime coilpacks on the two uper slots I still got the p0304...so replaced the coilpack that actually sends spark to #4 and drove to the credit union. Ran great. No p0304.
Oh and the EGR valve i got off amazon....made so cheap couldn't even tighten it down. I got one from Autozone when i purchased the 2nd coil. Now 2 new coils and 1 that hasn't ack'd up. So it's running great at the moment. ....We'll see if anything starts malfunctioning. I did get the p0401 about 1 or two miles down the road. I don't even care if it just keeps running properly.

I'm not even gonna get ito the trouble it was to take out #4 spark plug just to look at it. Gotta be the hardest plug to reach on this car.

 

[Mad_Coachman]

I'm not even gonna get ito the trouble it was to take out #4 spark plug just to look at it. Gotta be the hardest plug to reach on this car.

#6 was the most difficult for me. I have secondary air injection adding to the obstacles. 😉

 

[dadymurano]

Drove the car again today. Also drove it to the store two days ago. It's running good, but i still get the po401 code. This is aftr the cheap EGR Valve never got put on because it litterly broke when tightening the two holddown bolts, and I purchesed and replaced it with a lifetime delco from autozone.

So thinking back as to what all I've done and some of the problems I may have had a MAF problem, a purge valve issue..and while trying to fix it at least 1 coil pack started to act up. The coil pack issue seemd to "almost" coinside with the replacement of the ICM. That ICM gets hot. I did use heat sink greas on it.
So the cranck sensor didnt fix it. The cam sensor did not fix it.

I need to drive it more to see if it's back to the old car it was. I think I had an O'shit post some time back.

I'm not getting any po30x codes and the acceleration is good. The idle is smooth. I'll update as I can.

Wish this thread could have an ah ha moment, but it might not? Very glad so many have tried to help.

Ran great today. We'll see. PO401 is consistent, as it has been from the time I've owned this vehicle. That problem could be due to my replacing the Intake and MAP sensor when I got the car, although it ran great (several years but not a ton of miles) until it didnt.

 

[dadymurano]

1 more thing that I really didnt want to confess, but must is the MAF sensor I 1st bought after the fuel pump replacement didnt fix the problem is cheap chineese Amazon MAF that no longer will work properly on this engine. Maybe it never did. The pull-a-part ones off the 2004 lesabre seems to agree with this engine.

 

[lilpoindexter]

Damn dude, use good quality parts. They are cheaper in the long run. I had the stalling problem after you did, a maf and crank sensor got me fixed up proper. Listen to the mad coachman advice.

 

[dadymurano]

Time will tell. The cheap MAF sensor has been replaced, several parts ago. If I had to say it's fixed right now I'd say the ICM and or the Vent control Vale "Possibly" was the original cause.
I still want to drive it more and look at the info from some of the pids.
After I replaced the ICM It seemed like I sterted gatting the P030x on occasion, which was corrected by replacing a coil or two.

Anyway, I've driven it a few times now without an issue.

 

[John Canon]

Time will tell. The cheap MAF sensor has been replaced, several parts ago. If I had to say it's fixed right now I'd say the ICM and or the Vent control Vale "Possibly" was the original cause.
I still want to drive it more and look at the info from some of the pids.
After I replaced the ICM It seemed like I sterted gatting the P030x on occasion, which was corrected by replacing a coil or two.

Anyway, I've driven it a few times now without an issue.

Go, Daddy, Go !

 

[Designmore]

The pictures are just the work I've done since i first got the car many miles ago.. The one picture shows where i replaced the intake manifold with aluminum water elbows, new MAP/speed density sensor, evap switch new plugs and wires. --- Did great for a long time.

I bought a new pressure regulator that goes on the fuel rail. Got the fuel pump/module from rock auto. It is doing fine. The one time the car shut off the pressure guage still said 50psi.

Today I just received a crank position sensor - AC Delco Gold along with a cam position sensor, also AC Delco Gold. I don't buy junk.


The car has run prefect with an occasional po401 and the dash msg to check my gas cap. This has never affected my car/engines performance.

It's my hope that an intermittently bad crank and or cam sensor can cause my problem even though there are no codes.
I'm going to change them both. If that corrects my issue I will not know which one was intermittently defective. I'm OK with that as long as the engine quits dying and running like shit.

I've moved on past a fuel pump or fuel regulator issue. I suppose an intermittently bad injector could be an issue. But a fuel injector stuck open should cause poor fuel psi and very rich with a po30x associated with the cylinder it feeds.

I'll update after replacing the cam and crank sensors. It's a somewhat perplexing issue.

Although you replaced the MAF sensor, disconnect it and see if there's a change.

Hi: I have a somewhat similar problem. I unplugged the MAF sensor and there was no change. Does that mean the MAF is bad?

 

[Designmore]

Checked for vacuum leaks, but was pretty sure I'd not find any and didn't. I't not be so intermittent if i had a vacuum leak. Unplugged the purge valve and it had no effect. It's running fine at the moment just idling in the drive. The iat shows the proper temp. I can unplug all the sensors on the intake - iat, maf, map, egr, evap sensor, tps, and it continues to idle fine. Obviously it will not rev up properly with all the sensors unplugged but it will start right up and idle.

Left the fuel gauge connected for 45min with the engine off with no leak down in pressure. Went from 50psi to 49.8psi over that time period. I see no reason to check the gas flow specks. The pressure gauge stays steady at 50psi when revving the engine.

I'm gonna find my old laptop with the diagnostic program and elm connector so I can drive it around while monitoring live data. It's that or throw more parts at it trying to guess at the issue.

Hi: Shouldn’t the engine die if you unplug the MAF sensor? If it doesn’t die, doesn’t that indicate a bad MAF sensor?

 

[John Canon]

The PCM uses inputs from multiple sensors to determine spark and fuel outputs. If you have a code showing, then follow the preliminary checks and tests from the factory manual. It's called DTC Descriptions.

 

[Homer Jay]

Designmore,
Start a new thread and provide as much detail as possible to your specific issue(s).
Include mileage, maintenance history, what you have tried.

 

[BuickGirlFromMars]

GM HEI came out in 1975. I worked for a GM shop & we would bang the spark plug gap down to .045 when we changed plugs. I believe there was a GM service bulletin stating intermittent problems with the early HEI's spark jumping a gap of .060.

1974 but I think corvette got it a year earlier than others, or possibly medium duty got it a year later. I think I6 hei came out a year late too. i could be wrong but 74 a sbc definitely, under normal situations, had HEI
Later HEI with better coil, modules, advance weights, distributor other things, cap design is the best. like 77 or something maybe..