ANSWERS: 11
  • Well since the truck works fine, just has a problem cranking and starting, I would check the starter. This seems like the most likely culprit since you said it works fine and idles properly after the vehicle is up and running.
  • Thanks, but the starter is fine, the battery is fine, and the cranking speed is normal. I suspect a 'cold start' problem, but not sure if this is related to the PCM, temperature sensor, or what? Any ideas?
  • There are two sensors that would be the likely cause. The intake air temp. sensor, or the coolant temp sensor. If no engine light is on, it may not throw a code on a code reader, but you should have it checked anyway. (My f-150 showed no codes, but had a bad coolant sensor.) Your local auto parts dealer will usually do this for free. The temperature gauge sending unit, and the temp sensor for the fuel system are separate units.
  • Thanks! I had suspected the coolant temp sensor because the PCM doesn't seem to recognize the colder weather in the morning. I'll check both sensors.
  • Perhaps it could be the CAM sensor or the fuel pump check valve.
  • Possible - I can understand the CAM sensor affecting timing, but why would a bad CAM sensor affect the injectors? My understanding is that injector timing is controlled by crank position.
  • Fuel pressure supply or the regulator could be going bad- this is a pretty standard thing for and EFI system. when you turn off the engine the pressure should remain for at least a week at 5 lbs below spec or the reg. is not closing/sticking. just have a mechanic put a pressure gauge on it and see what it does overnight, also there is a pre-run for the fuel pump when you turn on the key for the dash lights, turn it on and listen for the "buzz" under the back by the tank, it's about two secs and this gets the pressure back up.
  • I've replaced the coolant temp sensor but that hasn't helped. Also, the cranking speed is fine and the starter is in good shape. Still no check engine light. I'll check the fuel pressure and the pre-run of the fuel pump next.
  • I've replaced the coolant temp sensor but the problem remains. I'll check the fuel pressure regulator and the fuel pump pre-run next.
  • I have the same problem . I have a 2002 2.3L. I have changed the fuel filter and the IAC. could someone explain the fuel pump pre run tst.and where is the regulator. Thanks Don
  • It is your fuel pump check valve. You can test for this by turning on your ignition key, wait for the abs light to shut off, turn off your key then immediately turn it back on and again wait for the light to shut off. On the third try, turn your key to the start position as soon as the light shuts off. If the car starts normally, it is your fuel pump check valve.

Copyright 2018, Wired Ivy, LLC

Answerbag | Terms of Service | Privacy Policy