Re: '87 5KTQ performance trouble

["Douglas Hurst Quebbeman" <dougq@iglou.com>]

> I am looking for some answers regarding my '87 5TKQ (150,000 miles).  

I have an '86 5KcsTQ, basically, the same engine.

> I am currently experiencing some driveability/performance troubles that
> myself and the dealer have been unable to resolve.  
>    My first problem is the car starts to stumble about a minute after a
> cold start.  This continues until it is fully warmed up.  Even after is
> warms up there is very mild surging at partial throttle.  I have tried a
> warm regulator from '88 5KT that is running fine and that didn't help.

By "warm regulator" do you mean the control pressure regulator?
Or, do you mean the Idle Stabilization System?

>  Second,  the car very rarely  exceeds 1.2 bar of boost.  Once in  a
> while it seems to run great (1.4 bar I think is normal) only to return
> to it's pokey state after a couple miles or after restarting the car.

I've only seen 1.4 bar once or twice since I bought my Q last 
October. Most listers seem to indicate that this is normal.

> The throttle switch and ECU have been replaced and also various breather
> hoses so there shouldn't be any vacuum problems.

> Occasionally the check engine code 2141 for knock sensing comes on.  I
> have tried all grades of fuel so I don't know what to think there.

Ok, I was getting q 2142 for a while. I started tracing the wiring 
harness that leads to the knock sensor. I "jiggled" the wiring 
anywhere that it passed through a grommet or cable tie. The code
went away, so an intermittant break was causing my problem.

I got a bit more performance back after I cleared up that code.

Hope that helps,
Doug
 
--
-Douglas Hurst Quebbeman (dougq@iglou.com)            [Call me "Doug"]
    QuattroClub USA# 4536              Audi International # 100024
       74 100LS Auto, 77 100LS Auto, 84 Coupe GT, 86 5Kcstq   
"The large print giveth, and the small print taketh away."  -Tom Waits