Rough Idle when warm!
#1
Racer
Thread Starter
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Hey All,
I have an 85 manual 32v. The car has recently started to idle rough, engine knock, hunting idle after I drive her and restart after about 30 minutes? Ive been told maybe a temp sensor 2?? Thanks for the help.
Dan
I have an 85 manual 32v. The car has recently started to idle rough, engine knock, hunting idle after I drive her and restart after about 30 minutes? Ive been told maybe a temp sensor 2?? Thanks for the help.
Dan
#5
Burning Brakes
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The throttle position switch on the '85 is on the throttle body, a three wire lead comes from the switch to an in-line connector near the inspection electrical connector on the front of the engine next to the oil fill (unless the connector has been eliminated such as in my case). You should be able to check the throttle position switch function without taking any of the intake system apart.
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#12
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Danny,
bring it over tomorrow night, we can do an intake on my truck, your car and have a good time.
Mine started doing the same thing yesterday.![crying](https://rennlist.com/forums/graemlins/bigcry.gif)
If it is the Temp II, we are out of luck, Rog is out of the country until Monday, but my driveway would look cool with 2 broke 928's and one truck with the hood up.
bring it over tomorrow night, we can do an intake on my truck, your car and have a good time.
Mine started doing the same thing yesterday.
![crying](https://rennlist.com/forums/graemlins/bigcry.gif)
If it is the Temp II, we are out of luck, Rog is out of the country until Monday, but my driveway would look cool with 2 broke 928's and one truck with the hood up.
#14
Addict
Rennlist Member
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The rough idle part doesn't sound like the TPS. More like the temp sensor. If the car is hunitng, it doesn't know what to do with it's flappy and fuel. It thinks its still cold when it is warm...and then realizes its warm, but thinks its cold...then realizes.....
#15
Racer
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Oh yes it does.... I've seen bad idle switches cause erratic rpm behavior when hot. Sometimes it is just a matter of adjusting the cable which is too tight, or lubricating the cable assembly which is fitted on the side of the intake assembly. The rpm moves slowly from 700rpm to 1000rpm and back.
Temp2 would be another option, as well as the LH ecu. When bad, the ecu believes the engine is still cold and creates a very rich mixture which makes the hot engine stall, and the idle stab brutely kicks in to prevent the engine from completely stalling. That gives a rough idle going 300rpm-2000rpm pulsating.
Temp2 would be another option, as well as the LH ecu. When bad, the ecu believes the engine is still cold and creates a very rich mixture which makes the hot engine stall, and the idle stab brutely kicks in to prevent the engine from completely stalling. That gives a rough idle going 300rpm-2000rpm pulsating.