[V8] Missfire with A/C on

[Kneale Brownson]

On my 200q20v I had the same issue that was the subject of an Audi recall
fix way back when.   Seems the clutch in the A/C compressor kicks up a jolt
of power that gives the ECU  a shock.  Another symptom common to this
problem is a loud pop heard on the radio when the jolt occurs.  The fix was
to replace the A/C relay and install a little wiring harness insert into
the wiring to the compressor clutch.  There's discussion of this issue on
Scott Mockry's website:  http://www.sjmautotechnik.com/elec.html#click
That little harness and relay were pretty pricey from the dealer.  Scott
may have a better price.

At 12:23 PM 2/19/2004 +1000, greg.moyle at mainroads.qld.gov.au wrote:
>
>
>
>
>Help,
>My 90 V8Q auto has developed a misfire or more a total cut-out but only
>when the A/C is running. It seems to only be a problem above 2000rpm so
>cruising around town isn't to much of a problem. When highway cruising the
>motor seems to cut out momentarily every 40 seconds or so but sometimes
>will run for a couple of minutes before doing so. The cut-out is so bad
>sometimes the box will drop into limp mode but a restart will fix that.
>Without the A/C on no problems even under heavy acceleration. This weekend
>we have 41 degrees Celsius so the Black Audi will be staying home I think,
>not much fun in a black car in that heat with no air.
>
>Any advice would be greatly appreciated.
>
>Cheers
>Downunder Greg
>
>
>
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