Need Help?

2004 Chevrolet Colorado 1SB LS Z85 Crew Cab 126.0 WB

2004 Chevrolet Colorado
Trim Info:
Rear Wheel Drive, Crew Cab
20 mpg city / 27 mpg hwy
Other Trims
Do you own this car?
Estimated Mileage
 Miles
Enter current mileage for most
accurate info about this vehicle


Track Your Service Records
Get Recall Alerts
Get Updated Value Estimates on Your Car.
back to question list

Ask the Community

Ask Our Auto Mechanics


August 10, 2013, 2:04 pm

Richard S
 

Question: Why will truck start sometimes and sometimes it wont?

Every once in a while truck will not start. Fuel pump is building pressure and starter turns over fine but it wont crank.


August 14, 2013, 8:57 pm

Ron W
Expert Mechanic

May be the Crank Position Sensor is not working well. It sends out the RPM signal to the PCM. If it is bad, there is no RPM signal, and the PCM will not command the injectors to fire and/or the ignition coils to spark. Easiest way to see if it works is to hook up a scantool and crank the engine. Monitor the datastream for RPM. If you see RPM then the sensor is working, if it reads zero RPM, then there is a problem with the Crank Position Sensor circuit.


0/0 users found this helpful.

Ask our panel of certified auto mechanics a question. We pay for their advice so you don't have to