Hey Guys, I have a problem with my check engine light coming on. The problem seems to occur when driving around in the city at about 1300 to 1500rpm's, I can feel me truck sort of bump down and the tach goes back to idle speed, no matter where my foot is. The engine will only idle for 3 to 4 seconds, then it pops back to life. I have found that after a few cranks the CEL goes out. I have noticed no difference in fuel mileage and/or power after this happens. I took it to the dealer and they upgraded my PCM, this did nothing but cost me $63.00. They also said the TPS/PPS and crank position sensor would need to be replaced if the problem continued. At $500.00+ I thought this was pretty expensive, as they couldn't tell for sure if these were even the problem. I respectfully hope some of you have had this same problem and can help. My truck is a "98/2500/24 valve, 106K miles.

 

Have you checked your codes?
Here is a site that might help with that. Some of the supply houses will read them for free (Advanced Auto, Auto Zone)
http://www.troublecodes.net/chrysler/

 

Thanks for the reply, I forgot to mention, I can hold in my odometer/trip reset and cycle the key 3 times and the check mode starts but when it finishes no codes are displayed. Sometimes when I do this the CEL is reset. Also my mechanic says that the brake control boxes can sometimes play havoc with the PCM, I called a tech at Hoppy and he agreed but didn't know what to do about it.

 

Hey Stout Ram, Welcome to the site! ;D

Have you read the article concerning the Crankshaft Position Sensor ? It sounds like you may be having the same symptoms as described by folks who have had the CPS going bad. I've heard cases of the TPS (throttle position sensor) doing almost the same thing, but the CPS is cheaper to replace at only around $65 bucks or so. I have read cases where some guys were able to clean the TPS with electrical contact cleaner and it would take care of the problem for a while, but not a permanent fix. The article for the CPS is in the RECENT ARTICLES section to the left of the screen or you can click on the blue link above.
Another note is that I don't know if your 1998 will show codes on the odometer like some of the other year models. I know that the 1999's will not do it.
You might also try to do a search and see if you find any helpful info concerning the crankshaft position sensor or TPS.
Maybe someone else will chime in with more info also. Hope this helps and let us know what you find out.