Strange Problem with the engine

[OutbackDiesel]

I have a problem with my 98. 5, the engine will on occasion, maybe once a week (so far) die out. It only happens at maybe 5 to 15 mph. I'll be running not very high RPMs maybe around 1600 to 1800 and the engine will just drop right to idle. It will Idle fine and I can get no response what so ever from the accelerator. Then a few seconds later, whatever it is stops and everything works fine again. I then have a check engine light which will go away after three or four times of cycling the engine on and off. Any idea of what this can be? My fuel pressure is good. Never lower than 5 psi and that's at WOT. Otherwise it's 9 to 11.

 

[CumminsAholic]

I dunno if I'm right, but it could be a TPS. (Throttle Position Sensor) A lot of guys have them go bad and this seems like a symptom that they'd have. Maybe someone that had one go out will chime in.

Corey

 

[Vaughn MacKenzie]

It's the APPS, aka TPS

OutbackD, I had a '98. 5 QC 4x4 5-speed for awhile and I had the EXACT same symptoms. It kept getting worse and worse. Replacing the TPS cured the problem. The downside is, it ain't cheap. This occured a 49,000 miles.



I bought the '98. 5 used and it had this problem when I got it. Between myself and the original owner, we got the dealer to replace it under the 100,000k mile warranty. You might try that route but it all depends on your dealer. In my case the dealer snitched one off a new truck and gave it to me then wrote up the new truck as having a bad APPS.



Good luck,



Vaughn

 

[Steve Campbell]

Vaughn, I am impressed with how "suave" you must be talking a dealer into doing "that" for you. Were you probably Oo. Oo. Oo. out to your truck after leaving the dealership.

 

[OutbackDiesel]

I'm not sure there is a throttle position sensor on my truck. Arent they on the automatics only? I would think there would be one on all of our trucks, but I was looking at a repair manual and it said on automatic only pointing to the TPS... .

 

[Mark_Kendrick]

All 24v must have a TPS as they are computer controlled. We don't have a lever or the like on the injection pump to pull to set the throttle.



Someone correct me if I'm wrong.

 

[RustyJC]

Originally posted by OutbackDiesel

I'm not sure there is a throttle position sensor on my truck. Arent they on the automatics only? I would think there would be one on all of our trucks, but I was looking at a repair manual and it said on automatic only pointing to the TPS... .

Are you sure the book wasn't pointing to the cable that transmits the throttle position to the automatic transmission? Only the automatic would have that cable.



All of the computer-controlled trucks should have APPS's - that's where the computer gets its signal from what you're doing with your right foot.



Rusty