Skip to main content
Topic: Idle Speed Sensor (Read 983 times) previous topic - next topic

Idle Speed Sensor

My 87 Cougar is having a little difficulty.  When I start it up and after it warms up for a little while the car will idle at a very low speed.  Then often times it will go ahead and just die. Would this indicate a bad speed sensor? Also as a side not when this happens the voltage goes down as well.

Idle Speed Sensor

Reply #1
Voltage drooping is simply because of low engine RPM.  Not uncommon. 
 
Knowing what engine/injection system you have would probably help diagnose the problem.  If it's the 3.8 with CFI, yes, the ICM is quite possibly dead, but I'd check connections to it first before replacing it.  That ain't gonna be cheap, IF you can find it.
:birdsmily:
(X2) '86 Thunderbird, 3.8L CFI, C5 Tranny
 
'92 F-150, 5.0L EFI (SD), M5OD Tranny, 3.08 Dif
 
'70 VW Beetle, 1780cc, twin Solex 43's.

Idle Speed Sensor

Reply #2
Does it idle ok with the IAC unplugged?
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.


 

Idle Speed Sensor

Reply #4
Ok so can a person have the same problem with a 2.3 ltr. I have the same issue after replacing the TPS I am still having problems with it idiling after worm up?
Can any body help
88 T/C 2.3ltr
gillis boost valve