Thread: Alt. Died. I replaced, Now my idle is wierd.

Last night when going to work i noticed my battery indicator light on. I was told by a fellow member to test the ALTERNATOR and go from there. I drove 30 miles to the nearest Advanced had it tested. Car showed 10volts and sure enuff it was bad.

Ok.... Figured as much anyways. I bought a new one. $182.00

On the way back home. ABS light and TCC comes on. Ok... this is weird.

SO 10 miles later the lights and power start fluctuating and it's holding in 3rd. It's not going to OD either. But as long as i keep my foot at a consistant 3k it will stay running.

5 more miles, i loose all electrical. I decide to try to make it 15 more miles to my residence. I get into town start to slow down and it dies for good. I cost a mile and let her rest.

Get tools, get a charger and change the alt in the County fairgrounds lot.

Start her up and the idle sounds like I have a cam.

I just replaced the MAF last week. I unplug it and it idles smoothly but at 1500k and will not "Kick down" to it's normal idle. I get home put it on the charger for the rest of the day until the wife gets home. It has a full charge and showing 12.5 volts.

I start her up tonight to go to work and the idle is still funky. I unplug the maf again and the idle smooths out. Then i plug the MAF back in while running and its still idling smooth but at a higher RPM around 1500k.

I put it into Neutral at a stop light while waiting and it goes above 2000k on the tach. Put it back in drive down to 1400k. I drive it to work and shut it off then start it back up.

Idle sounds like i have a Cam again but lower around 800 to 1000k.

I am stumped. Did the power fluctuation when i was driving it Screw some sensor up? Did i miss something ? Everything is plugged in. I've looked at the vac lines. I can re-examine them though.

One member said it could be a bad ground causing Hell

Please help me out guys i'm in great need.

Thanks in advance.

-Ryan

PCM Maybe?

And re-check all the vac lines and T's

Ya i'm gonna give it a good rundown on all of the Vac Lines. I could have knocked something off. (Hopefully that's all it is.)

I don't need these problems right now. I'm in the process of buying my first home.

EDIT: Just looked over the Vac Lines here at work and they all seem good. I'm still stumped.

TTT Need Help Guys...

First thing I'd do is allow it to idle in gear with the wheels blocked and ebrake on. Sometimes it can take up to 30 minutes for a car to relearn idle.

Being that your battery went very low, it's possible a sensor or pcm may have fried, although that's less common. Most likely the car is merely pissed at you for not swapping the alt in the parking lot at the store.

Originally Posted by BillBoost37

First thing I'd do is allow it to idle in gear with the wheels blocked and ebrake on. Sometimes it can take up to 30 minutes for a car to relearn idle.

Being that your battery went very low, it's possible a sensor or pcm may have fried, although that's less common. Most likely the car is merely pissed at you for not swapping the alt in the parking lot at the store.

LOL

I have an all data account and just came across this idea.

Could it be a IAC ? "Idle Air Control

Description From Alldatadiy.com:

The position of the IAC pintle affects engine start up and the idle characteristics of the vehicle. If the IAC pintle is open fully, too much air will be allowed into the manifold. This results in high idle speed, along with possible hard starting and a lean air/fuel ratio. DTC P0507 may set. If the IAC pintle is stuck closed, too little air will be allowed in the manifold. This results in a low idle speed, along with possible hard starting and a rich air/fuel ratio. DTC P0506 may set. If the IAC pintle is stuck part way open, the idle may be high or low and will not respond to changes in engine load.

Anyone think the IAC could be the culprit ?

I think a 100 things could be the issue. Could also be that the car lost it's memory on a few things when it was low voltage.

If you think it's an IAC or a MAF, go ahead and spend your money. It definately reduces the amount of things for us to try and diagnose.

If it were me, I'd ask myself.. what work was done, did any vacuum likes or wiring get pinched doing the work and what happens when the battery is unplugged for a long period of time or a pcm is swapped? That's the basic thing that occurred by running low voltage.

And yeah..I've been wrong before..and will be wrong again.

I hear ya. I've already asked others these issues. They said that it shouldn't affect the PCM, and it already has a new MAF took care of that last week. I looked at all of the vac lines twice last night and they are good as well.

Are you sure your still getting proper voltage from the alt&bat? Maybe a wire is crossed or something.

(Just brainstorming)

Try google-searching Grand Prix Idle Problems

are you sure that you didnt wreck your battery with the low voltage? Is the voltage at the proper levels now(what does it read exactly) that you have had the new alternator in there. You should not have to charge it now.........

Ok guys I feel really dumb. I went and bought an IAC and started to take it off at the store to put the new one on and noticed the Vac line on the TB was off. Put it back on, started it up and purred like a kitten. I went over those lines 3 times and never noticed it.

Good thing is that Oriley's took the part back since it wasn't installed and my car runs well again.

Vac Leak FTMFL!!!

Originally Posted by rynoman03

Ok guys I feel really dumb. I went and bought an IAC and started to take it off at the store to put the new one on and noticed the Vac line on the TB was off. Put it back on, started it up and purred like a kitten. I went over those lines 3 times and never noticed it.

Good thing is that Oriley's took the part back since it wasn't installed and my car runs well again.

Vac Leak FTMFL!!!

Thanks for all the help guys!

How'd you pop that off working on an alternator?

Originally Posted by rynoman03

Ok guys I feel really dumb. I went and bought an IAC and started to take it off at the store to put the new one on and noticed the Vac line on the TB was off. Put it back on, started it up and purred like a kitten. I went over those lines 3 times and never noticed it.

Good thing is that Oriley's took the part back since it wasn't installed and my car runs well again.

Vac Leak FTMFL!!!

at least it is fixed now........congrats