P1294 WHAT ENGINE?
target idle not reached, (means idle is wrong)
4.0L or 4.7L
means the ISC was changed by the PCM (commanded) and the ISC
failed to adjust idle to the correct speed.
clean the throttle bore.
clean the ISC.
or find intake leaks.
see chapter emissions here.
http://www.jeep4x4center.com/knowledge-base/index.htm?utm_source=cj#service
it means IDLE controls are out of control.
only that. and many things can cause that.
lean fuel mixture, gross misfire.
ISC unplugged?
a tech, checks all these things. the engine is running right
and when sure the engine is right, and holds closed loop at idle !!!
then and only then start testing the ISC.
we make sure it can move through its range.
and that the throttle plate is not blocked. for (any reasons)
and then make sure there are no vacuum leaks.
on MAP based systems, any air leak cases the engine to race
and if bad enough the ISC fails to work right. (for sure)
those are the hit lists. the tests are extensive.
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