HELP... 24 Valve rough idle
#1
09-30-2018, 06:25 PM
HELP... 24 Valve rough idle
Okay so i bought this truck and drove it with no problems except for having to rebuild the weak auto trans 
, but i was driving it for about 15 minutes and got it good and hot then i stopped at a store and when i came back outside to leave, when i started my truck back up the engine started revving uncontrollably up and down like i was stomping on the pedal really fast on and off. I turned it off and caught a ride from somebody else and when i came back later, it started up just fine and i drove it home. Ever since, this has happened maybe 4 times and once it happened while i was driving. I got to a red light and the truck shut off, when i tried to start it back up same thing happened. Ive always had a weird idle where it kind of sound like an intermittent miss, but now it seems more severe. Even when i rev the engine and hold it at a higher rpm i can still feel it missing intermittently. I checked the codes and i got P1690 and P0341. I have replaced the cam sensor, checked all the wiring between the TPS and ECM and the CPS and ECM. Since this started i have tried multiple repairs like replace the lift pump and injectors because of info found on other forums. I sure hope it isnt the VP44 or the cam reluctor wheel. What do y'all think? Any help would be appreciated
, but i was driving it for about 15 minutes and got it good and hot then i stopped at a store and when i came back outside to leave, when i started my truck back up the engine started revving uncontrollably up and down like i was stomping on the pedal really fast on and off. I turned it off and caught a ride from somebody else and when i came back later, it started up just fine and i drove it home. Ever since, this has happened maybe 4 times and once it happened while i was driving. I got to a red light and the truck shut off, when i tried to start it back up same thing happened. Ive always had a weird idle where it kind of sound like an intermittent miss, but now it seems more severe. Even when i rev the engine and hold it at a higher rpm i can still feel it missing intermittently. I checked the codes and i got P1690 and P0341. I have replaced the cam sensor, checked all the wiring between the TPS and ECM and the CPS and ECM. Since this started i have tried multiple repairs like replace the lift pump and injectors because of info found on other forums. I sure hope it isnt the VP44 or the cam reluctor wheel. What do y'all think? Any help would be appreciated
#2
10-01-2018, 11:06 PM
#3
10-02-2018, 06:26 AM
Something to try is when the truck is hot and acts up, shut the truck off, put a bag of ice on the top of the VP44 and let it melt down for 10 minutes. If it fires up and runs normally then it is an indicator that the electronics on the pump are in bad shape.
What year is the truck?
What year is the truck?
#4
10-02-2018, 11:26 PM
You need to concentrate on the Cam sensor and cam sync codes that you have. Until you chase those doen and sort them out, you may just be chasing your tail.
Pull the cam sensor and with a mirror and a flashlight (and a helper), roll the engine over and inspect the cam reluctor/gear. Then after that, if all appears well, reinstall the cam sensor. I don't know the voltages. So you will need to look it up. Check the output. If you have access to a scope, I would scope the output of the sensor.
Something you can try is to ohm the wires between the cam sensor and ECM. I would also do the same to the crank sensor.
Pull the cam sensor and with a mirror and a flashlight (and a helper), roll the engine over and inspect the cam reluctor/gear. Then after that, if all appears well, reinstall the cam sensor. I don't know the voltages. So you will need to look it up. Check the output. If you have access to a scope, I would scope the output of the sensor.
Something you can try is to ohm the wires between the cam sensor and ECM. I would also do the same to the crank sensor.
Thread
Thread Starter
Forum
Replies
Last Post
