[V8] driveability 2

[Ingo Rautenberg]

OK, John.  Let's see.  Idles OK when cold (extra rich mixture when cold
anyhow).  As the car warms up and the mixture is leaned-out.  The idle
stabilizer will adjust as much as it can, but if you have a major air leak,
the idle stabilizer cannot adjust fast enough.  I would take the Oxygen
Sensor out of the equation (when old or fouled can cause surging).  Then
(assuming you didn't wash the engine bay), I'd remove the air cleaner cover
and the air cleaner and the air cleaner support (two 10mm nuts/washers
attaching the lower air cleaner hosing to the intake of the intake manifold.

Then inspect the following hoses for softness or brittleness:

The small vacuum hose that loops around the intake orifice.

The large diameter hose that connects both valve covers (usually gets soft
over time and cracks)

The two hoses that connect to the throttle body.

Btw, if you did wash the engine, skip all those and simply remove the
throttle position sensor plug (2" long plug) underneath the idle stabilizer
and check for water ingress and dry out with paper towel and plug back in.
Voila!

HTH

Ingo


----- Original Message ----- 
From: "John Dodd" <jidodd at shaw.ca>
To: <v8 at audifans.com>
Sent: Friday, January 13, 2006 9:27 PM
Subject: [V8] driveability 2


> Here is more info on my previous problem:
>      1. Started the car  after sitting for 2 days. Idled OK at 1000
> rpm.When it got warm it started to miss again.
>  Rpm fluctuates by about 200-400 rpm always lower (800-200 rpm.)
>  The car runs Ok for 10 -20 seconds at a time then starts again with the
> idle issue ,then runs normal and so on.
> Drove around the block ,feels less power. Reved the engine, while in
> park at 4000 rpm but with difficulty.
>
> 2 .Read the ECU codes again. Came up with 2413 .Is it possible that I
> have a vacuum leak ?
> 3. My O2 sensor and FPR were changed 20000 km ago so I assume they are
> OK.
>
> Any pointers on where vacuum lines are located so I can check them ?
> Also how do I check for a bad injector ?
>
> thanks
>
>
>
>
>
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