Hey guys, I've got a 03 VIII with 55k miles on it.

Recently, I've developed a strange issue with the A/C. When the car is idling, I turn on the A/C and the car's idle falls drastically. For example: If I'm going on the freeway at 70mph and push in the clutch with the A/C on, the car will stall out. No matter what gear I'm in the problem re-occurs when the engine falls to idle.

To top if off, if the A/C is on and the car is idling, it will actually stall out and die. It seems that once the A/C is turned on that it drags the engine down badly. Feels like it has such a load on the motor.

Just for reference, the A/C works wonderfully as long as I'm in gear at any RPM other than idle. If I'm crusing at 70, the A/C will do just fine - blow ice cold air. Also, the car is throwing no codes whatsoever, so I'm unsure which direction I should take to solving this weirdo problem.

The car has a 12" Kicker CompVR in it powered by a KX600.1 amp. Not so sure this would be important, but i figured I'd toss it in there just incase it could be relevant. Also the car has been tuned for the 264/264 cams it has in it. Once again, doubt it's relevant but I figured I would address this.

One time, when the car stalled out, it threw a check engine light. I scanned it and the code showed up as cam position sensor & crank position sensor. I'm assuming this is because it stalled out so abruptly. I cleared the codes and they have never returned.

I searched the forums looking for similar issues to no avail. If any of you guys have any ideas on where I could start looking for a solution to my problems, or if anyone has had similar problems, let me know. I'd definately be greatful.

Thanks in advance!
Jared

 

It could be your cams giving you the bad idle with the AC on. How long have you had them? Also, I would check to make sure that the pully on the AC compressor to make sure the bearing is ok.

 

maybe a reflash would solve your problem. Your in TN...pm Mellon

 

Thanks for the quick reply.

The cams have been in the car for about 30,000 miles or so. However, I just had it retuned not too long ago. It seems like the issue has started since the tune, or after the stereo install.

The tune and the stereo is the only thing that has been changed since this weird issue has started.

Good idea with checking the pulley. There isn't any noticable noise with the A/C on, but it wouldn't hurt to check with the car turned off by spinning it. I'm going to try that.

Once again, thanks for the reply.

Anyone else have any ideas?

 

I just got a kick-a** tune about 3,000 miles ago. Car idles very well with the A/C turned off. Before the retune, the car didn't idle well, but the A/C did fine

Go figure.

 

Turn A/C off and roll down windows.
ha jk

Good luck finding your problem. I would reinstall stereo and see if it gets fixed

 

Haha, that's funny because I "almost" never use the A/C. Which is probably what took me so long to discover the issue.

I go to school 100 miles away from home and like to use the A/C on the highway. I really don't use it around town which is where I mainly use the car at.

Thanks for the advice though!

 

do you have upgraded injectors? getting the injector latencies wrong in the tune will cause this problem.

 

No, my injectors are factory stock.

Can you elaborate on this Mellon?

 

well if you have stock injectors there wouldn't be any reason for the tuner to mess with the injector latencies within the tune so that's probably not the issue. however, if you want to send me your rom I'll take a look at it for you and I'll verify that it has the stock latencies so you can rule that out and move on.

 

Sweet, thanks Mellon.

How do I send you my rom?

 

I'd check the cam sensor and crank position sensor for physical condition. If you have excessive end play on your crank (also known as crankwalk) it will start to eat the sensor on 7 bolt motors... It also shows symptomatically on some cars when you push in the clutch, which puts stress on the crank position... Hope that's not your problem, but better safe than sorry.

 

Thanks for the advice CO_VR4. I'll check these just to be sure. Everything runs so perfect though. The car runs really strong and does well with everything other than the A/C. I doubt this would be relevant, but I'll look into it anyways.

Once again, thanks for the advice!

 

send me a pm about this and I'll send you my e-mail address

 

PM sent!