car wants to stall after being stored

philsls1 · 03-04-2006, 12:24 PM

can anyone help me out? i have a 00 ws6 m6. it has been stored for 5 months in non heated garage with the negative taken of battery. I decided to go out and check the charge on battery and was at little over 11 volts. it was a warm day so i decided to start and let warm up. i hooked up negative and let sit for 3-5 minutes to let computer set. Car started right up and seemed to have low idle. After letting idle for few minutes i reved it up just a little maybe 2k rpms and seemed to want to stall when rpms dropped back down but it never did stall. It just fluctuated in rpms between 500-900 rpms. The car was stored with full tank of 93 octane fuel. can someone tell me why the low and rough idle? Does it just need ran a little or what? thanks in advance.

**2001NBMZ28** · 03-04-2006, 12:44 PM

Sounds like it's just relearning the idle because the battery was disconnected which reset the PCM. There's an idle relearn procedure but you shouldn't need it, just start it a few times and put some miles on it.

**2002Z** · 03-04-2006, 02:07 PM

i agree with nbm z-28 let it run it will come out of it

**Orcus79** · 03-04-2006, 02:11 PM

there could be many things why, fuel could have went bad if you didn't add stabilizer or there could be some moisture in the gas that may contribute.

**02z28ls1** · 03-04-2006, 02:26 PM

Go to the store and buy some Stabil fuel stabilizer and add per instructions. Otherwise drain fuel tank and run in your daily driver-if it's still any good. You have a summer blend of fuel in there-it will run different in the cold weather. I've had my car run exactly like that after letting it sit overnight in the cold for the first time. It's normally parked in a garage since it was new,the first cold night it went through it ran like you described,never did it again after that.

**iLIKEtransAMS** · 03-04-2006, 03:06 PM

I have a really stupid question, but it was said that when the battery was disconnected it computer had to "reset" and "relearn" the idle. If you had the car proffesionally tuned and then disconnected the battery would you have to have it tuned again?

**2002Z** · 03-04-2006, 03:16 PM

i store my car 4 the winter, and last winter the stock battery went dead,,,i didnt unhook the negative cable.....i went out and bought an optima battery.......started it up and it ran just like philsls1 car....ran like that for about 10 minutes or so.....havent had a problem with it since.....and i had stabil in my tank.

**01nhrata** · 03-04-2006, 03:21 PM

it's normal if the battery is unhooked, it's happened to mine every year since new. Just drive it once or twice and it's back to normal

**2001NBMZ28** · 03-04-2006, 03:21 PM

Originally Posted by iLIKEtransAMS

I have a really stupid question, but it was said that when the battery was disconnected it computer had to "reset" and "relearn" the idle. If you had the car proffesionally tuned and then disconnected the battery would you have to have it tuned again?

Nope, tune will still be there.

**SeVeReDiStOrTiOn** · 03-04-2006, 03:33 PM

Originally Posted by 2001NBMZ28

Nope, tune will still be there.

The tune is flashed in there...think of it as a mp3 player....even if the batteries die the songs are still in there until you delete them or record over them.

**chaman** · 03-04-2006, 04:00 PM

Recently this happened to me. I did the idle relearning procedure (as stated in the Helms Manual) and car has been running so well, even better than before. I think the procedure is there for a reason IMO.

**02z28ls1** · 03-04-2006, 04:35 PM

Wanted to clarify-I don't believe the problem is because of the old fuel,but it will be the cause of future problems.

**SeVeReDiStOrTiOn** · 03-04-2006, 09:42 PM

Part of the prob at first sounds like the intial relearn from having the batt off...i've forced re-learned a few times and it always dies the first turn over. The rpm fluctuation isn't good though...mine never does that, but I also don't store mine

Try adding some stabilizer in the fuel like the other guys said...also check the motor and make sure there's no critters under the lid or around the maf.

**y2konyxss** · 03-05-2006, 06:15 AM

my car does the same thing exactly after storage

i let it run for awhile then get the PCM to relearn and the battery to have decent charge then the car runs perfect about 10 minutes after driving.

philsls1 · 03-05-2006, 07:25 AM

thanks for all the info guys. i didn't put stabil in it before i stored it. didn't think it needed it with premium. guess ill go and get some and put in tank. cant wait until weather breaks up here in ohio to get it out and have fun! One more question. should i due the idle relearn anyway? i have read numerous post which say that their car ran better after they had done that.

**chaman** · 03-05-2006, 12:13 PM

Do it,

1: Disconnect battery for 2-5 mins aprox.
2: Start car
3: Holding the brake put it in "drive"
4: Let it idle in "drive" for 5 mins.
5: Put it in "park"
6: Let it idle for 5 mins more
7: Turn engine off for 30 secs
8: Have a beer......

After doing this my car just purrrs like a kitten!!

**02z28ls1** · 03-05-2006, 12:20 PM

What about a stickshift car-like your embryo is driving there.......

**chaman** · 03-05-2006, 12:33 PM

Originally Posted by 02z28ls1

What about a stickshift car-like your embryo is driving there.......

...ask your mom....

**iLIKEtransAMS** · 03-05-2006, 02:19 PM

Originally Posted by SeVeReDiStOrTiOn

The tune is flashed in there...think of it as a mp3 player....even if the batteries die the songs are still in there until you delete them or record over them.

thanks man

**ZeeVert** · 03-15-2006, 08:41 PM

I'm glad I found this thread. My Z has been parked for a few months, battery went dead, and I just got around to replacing it. The low idle freaked me out. I never heard of a car having to relearn idle. But that could be my problem. Thanks!