Bad IAC produce engine stumble at WOT?
Posted: January 20th, 2005, 10:30 pm
Brought the 94 RS into the dealer today hoping they could better diagnose what has become a time consuming thing to troubleshoot. The car has been down for a few months with the following symptom: Giving the engine hardly any air causes a severe miss/stumble/hesitation off idle. WOT from any engine speed makes the engine bog and the tach needle bounce from 1000 - 1500 rpm, never to improve.
There are no codes, timing's fine, new distributor, wires, and properly gapped spark plugs. Fuel pressure and regulator measurements all to spec...
But now the dealer tells me that the car needs a new IAC valve to start, potentially in addition to further diagnosis and repairs.
Since the problem persists at WOT (during which I thought the IAC valve isn't regulating airflow past the TB at all) I'm skeptical that this proposed $620 "first fix" is really a fix at all. I have no complaints about the way the car idles... it's everything *else* the car is supposed to do that it's no good at anymore (i.e. -- accelerate)
So what do you think? I'm sure it's true that I need the valve anyway. Should I have them order the part and keep working?
All input highly appreciated. -- especially if any of you BP swappers will sell me a working B6 IAC valve for $20.![Smile :)](./images/smilies/icon_smile.gif)
There are no codes, timing's fine, new distributor, wires, and properly gapped spark plugs. Fuel pressure and regulator measurements all to spec...
But now the dealer tells me that the car needs a new IAC valve to start, potentially in addition to further diagnosis and repairs.
![Shocked :shock:](./images/smilies/icon_eek.gif)
Since the problem persists at WOT (during which I thought the IAC valve isn't regulating airflow past the TB at all) I'm skeptical that this proposed $620 "first fix" is really a fix at all. I have no complaints about the way the car idles... it's everything *else* the car is supposed to do that it's no good at anymore (i.e. -- accelerate)
So what do you think? I'm sure it's true that I need the valve anyway. Should I have them order the part and keep working?
All input highly appreciated. -- especially if any of you BP swappers will sell me a working B6 IAC valve for $20.
![Smile :)](./images/smilies/icon_smile.gif)