97 Lumina, Random Stalling on warm startup

[1979lee]

Ok folks, Got a toughie for you...

backstory first, biught this 97 lumina with 78k on the clock(94k now), in august 2013...

NEVER a problem till last month. reliable quiet chevy, like i like.

3100v6 4t60e

on to the problem...

 

start up the car and totally random it stalls... but it will fire right back up. and them die again...

then it starts and the problem goes away for a few weeks, the BAM_O!!! does it again..

 

yesterday it did it to me and i mashed the gas and it stayed running. i proceded to drive it 25 miles with no problem.  it only does this crap AFTER its warm. never cold.. up to normal temps.

totally random.. not check engine light, i scanned it and no codes,

 

 

the only this ive done to the car recently is

 

july 2015  engine bottom mount

 

oct 2015  trans mount

 

nov 2015

alternator changed (old delco reman stopped charging)., and spark plugs. i went with the EXACT factory plugs and gap setting.

 

december 2015  oil/filter.

 

thats it!

 

the car runs normal, same mpg's, same power 

 

the only, only! things different the stock are

2005 3400 throttlebody

descreened maf (did this 2 1/2 years ago never a problem)

and the duel outlet catback off a 98 3800 monte.

 

thanks folks.

 

[1979lee]

Well... it happened again today...same thing...startup the car...a few seconds later...sputter and die

ARRRRRRRRRG..

.this is worrying me!

i have a trip planned for this weekend, about a 6hr drive...

 

anyone got a clue here?

 

halp!

[Cutlass350]

If there aren't any codes, my best advice is that you'll need to data log the problem. If you have an Android device, there's a good app "Torque" that works fine with an ~$20 dongle you buy at Amazon.

https://play.google.com/store/apps/details?id=org.prowl.torquefree&hl=en

 

I suggest getting the Pro version, since it's cheap and helps the developer to be able to spend more time and effort with the app.

 

Otherwise, the crank position sensor (CPS) is a known flaky problem across many GM lines. It's over a PITA to replace, since it's often behind/near the starter. And, you should get only a Delco CPS. The other brands are even worse. So, that's $30-$60 for the part and 1-2 hours for the R&R.

Some Torque App screen captures from my car:

 

 

 

 

 

Good Luck!

[RobertISaar]

I'd hook up a fuel pressure gauge to rule out fuel delivery issues.

[Schurkey]

Schurkey's Usual Advice:

 

Plug in a REAL scan tool, look at the data stream.

 

I'm betting on a failed Idle Air Control, but it could be other things.

[1979lee]

thank you all

dont have android phone...so no torque app.

i was thinking crank sensor, behind the balencer/pully right? is there a second crank sensor?

i know the cam sensor is near the p/s pump.

yes fuel pressure needs checked, anyone rent the tools for that?,cost?

I swapped out the IAC for another one i had. problem remains(i did this a month ago).

throttle body is clean, cleand the egr passage when i did the tb, it was clear and the egr itself was clean. very little blowby and very little oil use with this car.

 

gonna change the fuel filter , i changed it 2 years ago at 80k. so 15k on this filter... the one i changed was perfect inside totally clear.

 

so who would be able to put a real scANNER on this? not the stealer-dealer i hope!

 

thanks all.

[Cutlass350]

Also, ignition modules (for just about all EFI cars) are notorious for doing what you're describing.
If you wanted "to throw parts at it", I'd try that first.

 

You can get a good OBD-II scanner with data logging for ~$100->$200 dollars.

 

Heck, even my old scan-mate (it was $500+ when I got it) has good data logging. But, it does have a rather limited data capture amount.

 

 

[1979lee]

thanks cutlass,

 

nah, dont want to toss expencive parts at her.

i do have 2 spare ignition modules.. ill drop by autozzone, have them checked. if they test good ill try one.

that scan tool would be nice!.

in ten years driving a W, never been stranded or have major problems KNOCK ON WOOD,CROSS FINGERS!.

i hope this thing pops a code next time it stalls out.

been a good car. it sat a lot over the last few years. previous owner was elderly,but treated the car well.

my only real annoyance besides this, is a belly leaker a/c compressor. 

 

thanks all. keep ya updated.

 

heres the craiggslist add from 2013

 

[1979lee]

Installed my extra ignition mod today. no corrosion on the old one or the coils.

we'll see...... probably just in my rattle box aka HEAD but it seemed to run better with the different module. come to fine out the module is off my white 1998 3100 lumina, sold it 2 years ago!. see i was at the junk yard and i came across a almost new module, didnt cost me much, so i swapped them.

 

damn goofs af aauuto zone lost there test leads,so i can check the old module... i swear i'm never going there again(I say this each time i leave there)

 

lee

[wlkstout]

My neighbor had this problem with his 1992 3.1 cutlass supreme and it was either the ignition module or the ignition control module. I am leaning towards the icm if memory serves me right.

[worb4me]

Just throwing something out there, though it sounds sort of like but doesn't necessarily resemble identically probs I had with my old 1992 Lumina (ignition module and ecm). But perhaps suspect the fuel pressure regulator. Not likely, but to whatever degree your 97 resembles 3.4 Venture, it's a possibility. Godspeed.

[1979lee]

My neighbor had this problem with his 1992 3.1 cutlass supreme and it was either the ignition module or the ignition control module. I am leaning towards the icm if memory serves me right.

 

 

Just throwing something out there, though it sounds sort of like but doesn't necessarily resemble identically probs I had with my old 1992 Lumina (ignition module and ecm). But perhaps suspect the fuel pressure regulator. Not likely, but to whatever degree your 97 resembles 3.4 Venture, it's a possibility. Godspeed.

thanks fellas.

 

well so far no problems. drove well this weekend.

 

that spare ignition module is working good.

 

i pulled the vacumme line off the fuel pressure regulator, no gas present/smell.

it is the original.

so here's to lucky fix....

[1979lee]

WELL HELL.....

did it again today.....

engine up to tem.

 

went to the local fast food place drive thru. parked and ate our food. engine off, sat like oh 15 minutes.. started her up back out drove 100 feet and it starts stumbleing  i pop her in neutral and mash the gas... it clears up..... damn near died but didnt....

drove the rest of the evening fine. even spun the tires leaving the store( mini burnout) NO i wasnt trying!!!  besides that shiz is rough on an 19 year old car.

 i guess is time to take it in and have a pro look at it.  i dont know what else to do

 

STILL NO CODES or check engine lite.

 

i watched the tach while it was fouling up and is was droppping notmal is like 800 i think, dropped down to 500 before i revved it up and stableized .

 

          

[cutlassdude96]

try to get that fuel pressure check

[1979lee]

mini update,

 

 

no more stalling since 1-20-16... all i did was swap relays( the a/c compressor relay had the same numbers so i swapped the two) 

will this be the fix? i have no idea. but my a/c still works, and im not stumbleing or stalling right now.

 

I did Wiggle every harness i could get to under the hood.

[1979lee]

Update,

 

well it hasent stalled in quite a while . 

but yesterday i got a P0341 Camshaft sensor code.

see pic., will be getting a new sensor soon.

 

[Padgett]

When you replaced the IAC, did you clean out the passage, I have seen them really get gunked up and keep the IAC from moving properly.

 

Key is if the IAC command goes up while the RPM goes down then the pintle is probably not moving.

 

To reasd the IAC command everyone needs a ScanTool and some of the best (Torque Pro -$5) and a mini BT dongle (ELM -$8.98) are available for any Android device.

 

If you do not have an Android device then there is a very good one (I have the Pro version) for a Windows machine that is under $30. ( Also available from Amazon ).

 

Of course if you have an Apple there are scan tools but are not cheap.

[1979lee]

Ok folks, changed out the sensor this evening, wires going into it were all mangled , no insulation left on them, and the sensor was CRACKED and full of oil!.

 

iac is clean, i checked that (see my eariler post),thanks thought

 

 

Pics!

 

 

 

 

much thAnks everyone