Ford Repair Questions? Ask a Mechanic for Answers ASAP
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Ok and the theft lamp?
Do you have a 12 volt test lamp and are you comfortable doing some circuit checks with it?
At the moment its freezing outside. Otherwise I would. Well here is what happened. Eariler the car was running rough I checked it on my computer but before i could move it to my garage the car just lost power then stalled out. the code that came from the computer before the car stalled out was a misfire in cylinder 2. so this is where now i changed the coil pack. the other one had little cracks/ at the time i changed the spark plugs and wires still no go on the spark to the spark plugs. so i changed the crank sensor. still nothing
Ok when you said the other 3 are not getting power when cranking I assume you mean there is no flash with the test light connected to battery positive. The other three should not have power they should have a pulsing ground from the PCM when cranking. You had the test lamp on the positive side while cranking correct?
If it was checked correctly and there is no ground on all 3 wires then the PCM is not sending the ground pulse from any of the drivers. I doubt all 3 wires have a problem.
There are some more checks that need to be done. Using a long screwdriver hold it against the fuel injectors one at a time ( the ones you can access) while cranking the engine. Hold your ear against the handle and see if you can hear the injectors clicking when cranking the engine.
Using a voltmeter check for 12 volts at one of the injectors with the key on. One of the wires should equal battery voltage. Now find the DPFE sensor. Back probe the brown / white wire with the key on this wire should have 5 volts with the key on and the connector plugged in to the sensor. Let me know what you find. DPFE picture below. The DPFE is near the ignition coil. It might look different then the picture if it has been changed. It will have the 2 hoses going to it.
Ok theft system working normally
Hi, just like Kenny Z described above, with a test light, put the alligator clip on the battery positive (red one or will see a + sign on the battery) Next, with the coil pack disconnected, put the probe on any of the other 3 wires than the red one, and have an assistant crank, the probe should be touching the contact on the connector, not the wire itself. The light should blink. Test the other 2 while you are at it. If all 3 blink, then its time to check fuel pressure, using a fuel pressure gage, hooked up to the shrader valve of the fuel rail above the injectors (will look like a tire stem) Need to have atleast 45 psi here with key on or cranking to ensure engine is getting good fuel pressure. Thinking tests may have been done incorrectly, so lets double check for a pulse to the negative 3 wires on the coil, even if no flash, check fuel pressure.
Thanks! If fuel pressure bad, fuel pump is likely at fault.
Great! Where getting somewhere now, thank you for your patience. Really quick, any repair done recently prior to the problem happening? Or, has there been a heavy rain/ snow prior to problem happening?
It certainly does, recheck to make sure you have no codes in PCM (same a ECU ford terminology calls it a PCM for power train control module), if no codes, and no major repairs done, then yes, PCM sounds to be at fault, due to not being able to transfer the crank sensor information to control the firing (not a fact, but just my thought of the system). I would first definetly follow all wiring from the crank sensor to the pcm visually to see if a harness or wire is broken, if looks good, remove connector at pcm, and check all pins, make sure not corroded. If still looks good, reconnect after being disconnected, and try to start, if still no start, I strongly recommend checking all fuses in the engine compartment and in the car, with a test light with key on. Fuses should have power on both sides with a lamp connected to the negative terminal. If you find one with no power on both sides, disregard. If you find one with power on one side, and not the other, pull it out and visually inspect the fuse. Once all above steps have been taken, a pcm is possible, and should be installed at the dealer. Please request before pcm replacement that all modules be scanned for continuous codes, if still a pass, then yes the pcm is likely at fault. PCM's are usually never at fault, so that is why I recommended all of the above steps to help make sure 99%.