stalling at stop with A/C on

Topic: stalling at stop with A/C on (Read 857 times) previous topic - next topic

stalling at stop with A/C on

August 02, 2006, 10:49:26 AM

So I have a problem that started after I changed my alternator. When I have the A/C on sometimes the car will shutter when I come to a complete stop and stall and the charge light will beep and flash. Before I changed the alternator the car ideled at about 900rpms and with the A/C on it ideled at about 700 rpms. Now the car idels at 800 rpms and with the A/C on it idels at 600 rpms. I haven't done anything to the car but change the alternator. With the old alternator everything was fine and it didn't do this. With the car in gear and the A/C off the charge guage shows 4 bars (digital dash) and with the A/C on it shows 3 bars, same as before I changed the alternator. I can't figure out how changing an alternator would cause the car to have this problem or the idel to drop. That's all I did to the car and nothing else. Any ideas?

stalling at stop with A/C on

Reply #1 – August 02, 2006, 04:49:36 PM

The new alt. must be harder to turn. Maybe it's doing more work because it's not broke.

stalling at stop with A/C on

Reply #2 – August 02, 2006, 05:23:51 PM

same size pully on the alt. maybe the belt is too tight or something. its a stretch though...

stalling at stop with A/C on

Reply #3 – August 02, 2006, 06:27:56 PM

I tightened the screw on the bottom of the throttle body a bit to make it idle a little faster and it runs ok now. I don't know why changing an alternator would do this:screwy: . Any ideas as to why? The belt is at the right tension and the pully is the same on the new alternator. Maybe the car just wanted to be a pain in the ass because it's old:hick: .

stalling at stop with A/C on

Reply #4 – August 03, 2006, 07:40:18 AM

Quote

I tightened the screw on the bottom of the throttle body a bit to make it idle a little faster and it runs ok now

Make sure to check your TPS voltage now that you've adjusted the idle screw.

stalling at stop with A/C on

Reply #5 – August 03, 2006, 10:17:12 AM

Also check that Idle air control to see if it is dirty. Mine can be just fine then next time at a light it will idle low. Maybe you bumped it and some carbon is blocking the path. Flush it out just to be safe. The Iac changes the idle due to load. so when you turn on the a/c it should idle up not down.

stalling at stop with A/C on

Reply #6 – August 03, 2006, 10:17:44 AM

stalling at stop with A/C on

Reply #7 – August 04, 2006, 06:30:37 PM

Quote from: Paul Flockhart

Make sure to check your TPS voltage now that you've adjusted the idle screw.

I did that:D The first thing I did was clean the IAC. It wasn't really dirty but I cleaned it anyways. The car is running ok now. I took it for a hour drive last night and it ran fine so I guess it's ok.

stalling at stop with A/C on

Reply #8 – August 10, 2006, 07:18:18 PM

I have the Haynes Repair manual and it doesn't show the throttle body or IAC. I would like to try these out on my 85 because it idles really low and stalls out when going from park to reverse or drive unless the engine has warmed up considerably.

Also, while driving, the moment I take my foot off the pedal to coast down the street it very slightly jerks like i'm running out of gas (even though i'm not). Please help.

stalling at stop with A/C on

Reply #9 – August 10, 2006, 07:25:17 PM

Btwodu what engine do you have. If it is a 85 3.8 they have a really weird IAC on the side of the Carb type unit. If it is 5.0 it should still be the carb type EFI. Not shure about that one IAC. But also being the older model I think it still has the non computer controlled tranny. If that is the case it kinda sounds like the Modulator has went bad on the tranny.

stalling at stop with A/C on

Reply #10 – August 21, 2006, 02:38:43 AM

Cleaned the IAC on my 5.0 but nothing changed. It was quite dirty though. How do I check it to see if it still works?

stalling at stop with A/C on

Reply #11 – August 21, 2006, 10:31:54 PM

The bearings and such are probably better and tighter on the new alternator hense more pull on engine overall. I would suspect that was the problem. It's really the only thing that makes any sense.

tc