Ok, my problem started when I installed an A'pexi intake on my stock S5 TII. I installed it, everything looked fine, but when I tried to start the car, it would like start, rev to about 1,200rpms and drop down and die. Everyone was saying pretty much AFM wasn't plugged in right, or air wasn't getting in. It turned out to be the tubing was not tightened over the turbo with the screw clamp thing, and had come off completely. So at the time, I couldn't remove my air pump to get to the thing to tighten it. I drove home, having pushed it in as far as possible, and the car started up, but at stops my idle would drop below 1k and a normal idle, and bounce up and down like it was about to die, so I just tapped the gas to hold the idle until I got home.

I got home, and took the air pump out to get to the turbo, and I tightened the screw clamp on the turbo to give it a nice fit. Then I put the air pump back into its place and but the belt back on. Started the car up, and took it for a drive to find out that the idle problem had gone away. I drove around for the next few days without the idle going under normal, and keeping an eye on it. Then suddenly (I think when it started getting colder this week, and i'm not sure if that might be at all related) the problem slowly started coming back, and at some stops, it would idle fine, then the next stop it would idle like crap again. That lead me to believe that the clamp was still on, because if it had come off, wouldn't it idle like crap all the time, and not stop and go like that?

Then today it seemed like now at every stop it idles like crap, and its back the way it was before it was tightened fully. Now the wierd thing about all of this, is the fact that it seems like it may be electrically related to other things in the car. When I was at a light, after my car had warmed up inside, I turned off the blowers inside the car for the heat and the idle seemed to go up. When I got home, I played with this more to notice that it seemed like it was making a difference in the idle, when it was off, the idle would go up closer to normal. Another thing I noticed, when I didn't use the brakes, the idle would seem to stay better than when I used them. I put the e-brake on and pushed the brake pedal in and out and it seemed like that too effected the idle.

Another thing is the fact that my parking brake light is on. I thought it was just another screwy electrical problem until I read in another thread that the e-brake light being on all the time is a warning of something with the brake fluid? Could someone elaborate on that one for me?

So the short version to this all is:

- If the belt or something on the air pump was a little off, could the air pump cause a low idle?
- Could the low idle be too much electrical load and having extra stuff on be screwing with the cars electrical system?
- Does the e-brake light have anything to do with this crap? If so/not, whats the deal with it being on?
- Maybe the damn intake tubing just came off again and i'm too lazy to take out the airpump again? (althought I did try and tighten it down really hard).

- Brian

 

Somebody humor me and at least say you read the damn thing, lol

 

^^bump

 

sounds like there is some kind of faulty reading from the MAF. It could be the MAF itself but since it is speratic it could be the contraction of the connectors in the cold making some kind of leak. They are silicone right? Its a must for a turbo car. A possible vaccum leak could be the cause. hope that helped some

 

The parking brake light comming on is a warning that the brake fluid is low. It could also be a fault in the sensor or the switch on the brake handle itself.

The fact that your car is dying when you are using electricity (blower, brake lights, etc) tells me that you have a chargin system problem. This could be several things.. we'll start with the easiest 1) clean your Battery contacts (sounds dumb, but if they are corroded it'll mess everything up) 2) check your grounds and get an engine grounding kit anyway... 3) check your alternator.

I had a similar problem on my 88, when i hit the brakes, everything went bezerk... turned out to be a wire that i had pinched against the body of the car and it was grounding out and taxing the electrical system. Even after fixing the problem, i noticed that at idle, when i hit the brakes, the rpm would drop. I got a 3rd gen altenator off Silverrotor, set the idle a bit higher and the problem dissappeared.

Check all your vaccume lines and your gasketts.... do this by spraying carb cleaner on suspect areas. Whe you hit a leak, the car will die as the carb cleaner gets sucked through the lines and into the intake. example.. after installing my downpipe, the car wouldn't idle for ****, couldn't figure it out, then, i started spraying carb cleaner around and found that when i had taken the UIM off, i had screwed up the gasket and it was sucking air (I sprayed under the UIM where the secondary fuel rail is and the car fell flat on its face).

 

By carb cleaner you mean the carbon clean stuff?

 

It's an aerosol can that actually says carb cleaner on it. Any local automotive shop should have it.

 

Ok, thanks

 

First check that the damn thing is nice and tight.
Car idle drops with eletrical load? Sounds like a BAC problem.
You might also want to check and make sure tps is adjusted right.

 

Yea, Turbonut (he lives closeby and helped me out with my car before) suggested checking the BAC. He said:

I didn't get a chance to PM him back yet, but when he says remove the electrical connection, is there just like a single plug that I should pull and it will drop the idle even more, and if it does that, then its working properly and I should adjust the TPS?

 

yes there is one single connection to BAC, at least on my S5 N/A.. but should be same with turboII.

And yes adjust TPS.