Hi Guys, Yesterday I was just outside the PA line in a 1999 24 Valve when the truck started to jerk around hard, I pushed the clutch in and it was revving to around 3000 r's then to idle then back up so on so on...after it shut it down for a while and started it back up it ran ok but with very low power and no tach. I put my OBDII scanner on it and I was only getting 15psi boost MAX. And a fault code: P1693 which is DTC Detected in ECM Or PCM.????....???? Any replys would be helpful. As far as I know this truck is BONE STOCK. 160000 miles.

 

1693 is a companion code meaning exactly what you said it does, so you need to get a scan tool that can read both PCM and ECM separately, but a running problem will most likely be found in the ECM.

 

OK do you think it could maybe, just maybe be an easy fix??

 

I would have thought that if it was the crankshaft position sensor, it would show a P0336 code on your scanner plus the CEL would be lit up. At least this is what mine did when the sensor went bad in mine. It took about an hour to change mine out after finding the correct tools. The starter bolts can be a BEAR to break loose, but it was an easy job.

CLICK HERE FOR SOME GOOD INFO ON REPLACING THE CRANKSHAFT POSITION SENSOR

I think I would find another scanner to check for codes again if I were you. I hate electrical problems and it gets kind of expensive when you just start throwing parts at it.

Good luck,,,,,,