Ok i got a little bit of trouble wit my 98 24v. Sometimes i just lose power for about 3 seconds, the rpm drops and then the motor picks up to right where it should be.

It then puts the check engine light on and throws this code

P0121 APPS and Idle Validation disagree


Now is this the APPS screwing up, or could it be the crankshaft sensor. With the code i get i'd think it would be the APPS but could the crankshaft sensor be going and this is the code that it picks up?

I tryed reseting the APPS as per the tech facts but it still does this. Maybe i loose or bad connection?



Any help is much appriciated


Jeff

 

The APPS is the temporary loss of power and ,from what I understand, the CPS (CKP) will only cause a gradual loss of power.

The reset always worked for me until I got tired of doing it and finally replaced it. Had I seen the threads on here about re-setting the voltage, I would have done that first.

Look here.

 

When i reset using the method in the tech facts it only last me a few days. If i do the voltage reset method do you think it will last longer?

I've also heard the the APPS is grounded bad and that running the ground to the battery can make a difference.......anyone heard anything about this?

Thanks

Jeff

 

The re-set was only temporary for me too. I've heard about the grounding problem, but don't really have an answer.

I don't know how long the voltage re-set last. Good question.

 

My truck was doing the same thing for me but throwing the p0336 code.

IT turned out to be a bad crank sensor. cost about 76bucks at the dealer, changed it out and have about 1300 miles on it since then with no problems.