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Topic: 1988 cougar 5.0 idles high after using cruise control (Read 1348 times) previous topic - next topic

1988 cougar 5.0 idles high after using cruise control

after using cruise control the car will idle at about 2000 rpm for a few days then return to normal, i replaced the trottle position sensor no change any help would be great

1988 cougar 5.0 idles high after using cruise control

Reply #1 –
Tps?

1988 cougar 5.0 idles high after using cruise control

Reply #2 –
It almost sounds like the cable from the cruise servo is binding, and in turn, holding the throttle blade open a small amount.

It's easier to eliminate the other variables. You've already replaced the TPS, so why not remove and clean the IAC valve. They tend to get carbon build-up and have negative effects on the idle quality. If that checks out, you can look into the cruise servo and/or its cable to the throttle body.
[SIGPIC][/SIGPIC]

1988 cougar 5.0 idles high after using cruise control

Reply #3 –
clean the IAC made a huge difference in my car somtimes it would idle fine and then it would idle at 1400. make sure you buy a new gasket because i tryed reusing mine with some rtv didnt work that well.  when i cleaned mine i took it off and let it soak in a gallon can of carb cleaner and then cleaned it more with a spray can then put it back on and it makde a world of difference.

also take the intake tube off and start the car and shoot some throttle body cleaner in that too at the very top of the throttle body i found alot of junk
 

1988 cougar 5.0 idles high after using cruise control

Reply #4 –
pull your codes with a paper clip.

you can also pop the cruise cable off the throttle body and see if the cable slipps easy in and out.