5ktq Possessed oil pressure auto check

[Huw Powell]

On 10/19/2010 8:02 PM, John Cody Forbes wrote:
>   It's interesting these days after 10 years and having owned 8 (as many as 4 drivable at once and currently 3) that 5000's can still come up with new issues to bug me.
>
> Patient: My "fast" '87 5ktq.
>
> Symptom: Auto-check oil pressure warning comes on only at idle and about 75% of the times the engine goes to idle (ie most stop lights).
>
>   I have checked the black .3 bar oil pressure switch, it seems to do it's job correctly. Oil pressure via mechanical gauge is great. Tonight I unplugged and made safe the wire for the black switch and the problem persists. I did verify via bentley wiring diagram that the correct wire is on the correct switch.
>
> Any BTDT before I start tearing in to this thing? The autocheck triggers on ground to mean low pressure so it can't be an intermittent open, it's got to be an intermittent ground or a bad autocheck.


Are you sure the low pressure switch is NO?  I thought it was NC so a 
broken wire would set it off.

You apparently have plenty of spare cars to swap the sender into and 
test, why not try that?

-- 
Huw Powell

http://www.humanspeakers.com/audi

http://www.humanthoughts.org/