All of a sudden I am idling at 1300 rpm.
Checked all over for vacuum leaks and found none. I took the maf off and cleaned it lightly with either and it seemed to idle for about 10 seconds then back up?
What else can cause it?
To remove this ad, register today or login if you already are registered!
EDIT: On your 86.5 it is way easier to check the ISV than on an S4. Middle pin on the valve is 12v. Apply ground to each outer pin - one at a time - and you should hear the ISV move.
Last, on the S3 motors there is a shorty harness from the idle/wot switch to the main engine harness. It can also be a problem. Most original-equipment shorties are dead by now. The harness is NLA. You have to make a new one from new connectors. Or I think 928sRUs sells a pre-made replacement.
-- Dave C
Front-Engine: '94 928GTS 5sp; '91 928GT (Supercharged); '89 928GT
Mid-Engine: '14 981CS A$$-Engine: Soon
928 Owners Club Charter Member
Agree with Dave C., probably the harness for the idle/WOT switch. Mine disintegrated as most do. 928sRUs does sell a replacement since it is NLA from Porsche.
Automatic - Brand New 2.54 40% LSD Euro
Constantine (Black Sea R&D) Super Clamp
Porken Chipped, Ott X-Over
928 Spec Sway Bars
997 Carrera III wheels
2008 Cayenne S (Hers)
Fabspeed Secondary Cat ByPass