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Idle Problem

Trailbst

NAXJA Forum User
Location
Westerly, RI
87 4.0L Auto

I got this XJ for free.

It runs, it idled, then the idle would creep up, and up.

So I replaced the Throttle Position Sensor today.

When I restarted the Jeep, the idle immediately shot up to 3000 RPM.

What else could cause this?? Did I know off a vacuum hose?? Could that be the cause??

All help will be appreciated.

Thanks.

Erik
 
TPS Adjustable up to 1990

You don't mention adjusting it to get the output in spec- has to be 82% of input voltage if you have an auto tranny, at idle (throttle closed). Input should be about 4.8 to 5.0 volts. Back-probe the connector to test. 4xBob
 
I guess it's not as simple as just plugging it in.

Time to get a new Haynes or Chiltons for it.

How do you check the output??

Thanks in advance.


Erik
 
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