New Battery = Chaos

[93euro]

Ok so I had a new battery installed today (it was in dire need of one). when it was done, the guy who put it in said "well, the batt. and alt. test out OK...but you STILL have a stalling problem". i thought that was odd, because i haven't had a stalling problems since the ECM bit the dust 2 years ago. well i went out, fired it up, and chaos ensued. the revs were all over, and it stalled several times as i was driving around the mall parking lot. I was about to go back to Sears when it started to mellow out. it stopped mostly, so i left. all had returned to normal. I stopped up at my work for a little bit, and left. it started acting kinda funny again. then it stopped. now the only thing that happens is the lights dim a little at idle. what gives?

 

quick info - new alt at 93k, ECM @ 76k, thats about it. i got it at 70k.

[Crazy K]

my guess is ecm trying to relearn your car... which may mean you need a tune up.... One of my cars is really hard to start if you disconnect that battery. I think my oxygen sensor is giving a poor reading and I have seen inconsistances between both the temp sensors... (fan turns on with engine cold sometimes and not when hot... wtf?) and it runs rough and stalls for a few minutes when started after a battery disconnect... So i'm doing the temp sensor tomorrow

[Justin]

I agree with crazy k, I think it was learning the idle. If it really gives you problems I'd unhook the positive again for a few minutes and then reconnect it and start it without your foot on the gas, it'll probably die. Just keep starting it until it idles by itself. That's how I've gotten the nicest idles out of my cars, but I've never had much of a problem with them. The lights dimming was probably there before, maybe you're paranoid from the stalling? Either that or the learned idle is a bit low, but I wouldn't worry too much about it.

[manitcor]

yeah, prob just relearing, leave it idle for 10 mins or so let it get warm then take it on a nice highway crusie for about 30mins then hit the city and cruise around for 30mins or so

 

that should be enough to get the PCM to go through all its various learn cycles,

[3pt1lumina]

idle relearn, I never have a good time when I disconnect my battery even if I do this. My car is special. There is a short in the wiring for the IAC so everytime I cut power then reconnect, it blows the IAC out. Sucks for me but I highly doubt its your problem.

[nebojsa_o]

So if the car is in need of a tune up, and that's causing the big trouble re-learning, what all would need to be tuned up. o2 sensor, and what else is considered a "tune up", I've seen it used a million times, but I'm not sure what is all included in tunning the car... Fuel filter? Air filter, sparks? All that stuff, or is there a lot more?

[93euro]

yeah, you're probably right. this car has gone 40k without many things done to it at all. god for all i know the spark plugs could be original to the damn car.

[Crazy K]

most likely a sensor near the end of it's life, one that the engine bases fuel "metering" values on. I would say:

most likely:oxygen sendor

possibly: temp sensor for the ecm (located near the thermostat)

other to do stuff:

unbolt the EGR valve and clean the port, 3.1s clog there alot.

acdelco spark plugs, basic ACD plugs are fine. (NO BOSCH they FOUL!)

wires if they look old.

 

And my personal favorite... take the plenum off to inspect and replace everything, the injector O-rings, the PCV valve, distributor drive gear gasket... but only if your ready for a job! (let me tell you about the fuel rail I found that had been installed with a sledge...:! I DO Do this but it's not critical for you.

 

And don't hesitate to ask if you have questions on how to do any of this.

[19Cutlass94]

Weird, I can disconnect my battery all the time and I NEVER have any sort of problems, or anything mentioned above. The only thing it does, is idle a tad rougher, thats it, everything else is normal.

 

 

But just try a tune up. Plugs, fuel filter, and wires. if that doesnt work out, then try looking into what else could be going on. but if it has 40k on it with old shit on there, its better to do it reguardless

[Crazy K]

I stand with my recommendation

oxygen sensor (try autozone

plugs

wires if worn

and i forgot to mention fuel and air filter.

none of these would trigger a check engine lit if in poor but "operable" condition.

[93euro]

I've been thinking, and I'm REALLY pissed now. The guy at sears effing lied to me!!!! we he told me about the stalling problem, and i started to tell him that it didn't have a stalling problem, he told me that it "stalled on the way into the garage". Poor old lumi wouldn't do that . i told him that again that it hadn't stalled since the days of its failing ECM, and he just walked away!!! i wish i would have known about the idle re-learn thing then!!! eff Sears!!! i feel like going back there!!!! i wish this thing would have been all their fault!

[nebojsa_o]

Well, how is it running now? You said it was getting better, if I understood that correctly. Is it still stalling, or are you just pissed off now because he lied?

[93euro]

idle is a bit lower than it used to be. around 500. but its all good for now.as for that guy....GRRRR. he did other things that pissed me off, too. when he initially came in to get the keys and stuff, he saw that it was a Lum, and said "Oh i hate those cars! you have to take the windshield washer bottle off!!" i was standing right next to him. he just seemed cocky altogether. grrrrrr .

[1990lumina]

Mine has the bottle beside the battery ...still gotten rmeove that strut brace though

 

I'd do an idle relearn as well dude. Instead of disconnecting the battery, you should just be ab;e to ull the ECM fuse under the hood (right side the aux. postive terminal)...

 

Then start her up and put it in drive....let it idle with the brakes pressed for 6 minutes. Shut car off (I shut it off in gear)...start it up again after a couple seconds...put it into drive for another 6 minutes....if anything wrked properly idle should be learned.

[93euro]

i shall consider it. its ok for now though...as long as it's not stalling like earlier. that was scary!!!

[AWeb80]

when i had my battery unhooked for a week when i was relocating it....and then i hooked it back up and the car idled fine.....even with out power to the ecm for a week....how would my car idle fine on the first start....and all of yours has to do the idle relearn?

[Garrett Powered]

Your previous problems with the car indicate a poor ground on the battery IMO. Nobody has mentioned that all electronics rely on that one ground from the battery to the core support. the most common electrical problems like failed ECM and dimming lights, well all of them are usually because they don't sand off the paint before they thread in the ground bolt there, then it gets green and corroded.

[Crazy K]

AWeb80, it varies. if your car is in real good shape, tune-up wise, it may run fine when reset, the reset setting is the base values that the car would normally run at. The car only varies them when relearning the idle until satisfied.

In the case of the original lumina in question, those values are too low, so it stalls until the ecm tries using higher values. -Ken

[supreme_style21]

Did you do the idle relearn like everyone mentioned?? You'd be suprised what kind of things that can fix. Shops must make a TON of cash off these cars ,just by doing that.

I had bought an 89 GP a few years ago. It ran great. I changed the fuel filter the day I bought it. It would NOT run after I changed the filter. All I did was unthread the old filter and thread up the new one and it wouldn't run. It would crank, choke, sputter and stall. Yes it had to build up the fuel pressure and whatnot, but it had plenty of time to do that. I tried the idle relearn FOUR times and it ran great. After each attempt at the 'relearn' it would run a LITTLE better. You'd just be suprised at how much that stupid relearn can fix!