Rough Idle at Startup

**Audi Mind Trick** · 06-24-2008 11:47 AM

Ok so i have spent hundreds of dollars trying to figure out whats wrong with my car. When the car is cold or even slightly cold the idle is very rough, like the car cant breathe and its going to cut off.

This only last for about 20 seconds, unless I rev up the engine then it only last a few seconds.

I have replaced the mass airflow sensor, the primary oxygen sensor, also some cracked hoses on the crankcase ventilation system.

I have taken it to my mechanic AND the dealership and they don't know what it could be. I thought it might be something with my APR ship going bad or something but the guy at APR said that if its something that goes away when the car is warmed up its not the chip. He suggested something about the secondary air injection pump.

Lastly there are no codes being thrown

If anybody has any thoughts on the matter, they would be greatly welcomed.

Thanks

**f15046** · 06-24-2008 01:44 PM

Sounds like the SAI system. mine did the same thing. when cold it would idle like it was running on 2 cylinders, but when warm it idles perfect. I just upgraded to a Big Turbo, and eliminated the SAI system, and now the car idles perfect.

**Audi Mind Trick** · 06-25-2008 10:22 AM

LOL! I like the solution you offer!

But alas I can't afford a BT right now, I just want my car to run right.

Did you get a quote on how much it would be to correct the problem in your SAI system?

**Nebone** · 06-25-2008 10:25 AM

Mass Air Flow sensor can cause rough idling and so can the coolant temperature sensor. Look into those.

**317ssayzarc** · 06-25-2008 10:34 AM

pull those plugs...

**f15046** · 06-25-2008 10:43 AM

No i didnt get a quote, b/c i knew i was eliminating the system.

**Audi Mind Trick** · 06-25-2008 10:43 AM

I have replaced my MAF and coolant sensor already.

You really think the plugs could be the issue? That is an interesting thought. I replaced them about a year and a half ago with the NGK platinum plugs. They are supposed to be the best right?. Could it be a gapping issue as well?

**seanko04** · 06-25-2008 12:01 PM

It won't hurt to take a look at then you might be surprised. When I first got my car it would idel BAD at stop lights or just when I came to a stop. So I changed the plugs and what a difference.

**Audi Mind Trick** · 06-25-2008 12:22 PM

lol, yeah mine will do that too when i come to a stop, i will definitely be checking that thanks!

Would suck to find out that is the problem after I spent so much money on it already

**willowtreexx** · 07-07-2008 08:50 AM

can i just have a quick update if you fixed the issue. mines doing the same and before i repost on something i would like to know if you were able to fix it?