Coyote Gen 4 start-up issue
Good morning Forum,
My step-son and I are trying to troubleshoot the engine refusal to start.
He put the current situation in the following words:
My step-dad is building a pretty nice MK4 roadster with a gen 4 coyote crate engine-TKX manual gearbox from Fortes/Ford performance. The build is in its last phase right now, but we had no luck starting the engine yesterday.
We might need help since we are out of ideas. Here is what we have done:
Engine harness has been connected to the RF harness
• orange wire from ‘ignition’ on the key switch to the light green wire of the Ford harness for waking up the ECM/PCM (which should prime the fuel pump)
• light blue wire from ‘start’ on the key switch to the light blue wire in the Ford harness for the starter request signal
• Thick gauge green wire from the Ford harness is connected to the relay (orange wire cut in half and spliced to the green wire to activate the fuel pump relay and leverage the roll over switch from the RF harness
Here are the symptoms:
• Car cranks fine when the key is on start
• Throttle-by-wire pedal is functional once the key is on ignition
• Fuel pump does not prime
• No spark when we crank the engine
For the fuel pump (because we have read a lot of posts on this forum related to the same issue of not being able to start the Coyote, thank you all btw!!!!):
• The RF circuit works fine. If we put 12v on the orange wire on the relay, the pump primes to a nice 65psi in no time
• In the ford PCM, all the relays and fused were checked and are functioning
• In the Ford PCM, there is power to all fuses and relays so power to the PCM is good
• In the Ford PCM, if we put power to the White/Yellow wire coming out the ECM, it triggers the pump
For the ECM:
• The light green wire gets a pretty good 12v signal when the car is in ignition and start
• Like I said earlier, the Throttle pedal is active, so the ECM most probably has a tune
Error messages from the OBDII port:
• After the initial attempt at cranking, we checked for OBDII with a cheap OBDII scanner, and we got a ‘P06B8: Internal Control Module Non-Volatile Random Access Memory (NVRAM) Error’ which we cleared and never reappeared
• If we disconnect sensors, like the MAF sensors, we get error codes, so this works
• Interesting observation: the OBDII scanner does not seem to access all the modules (like the fuel control module). I am not super familiar with OBDII scanners and the Ford architecture, so it might be fine.
Any help, even simple suggestions, is more than welcome. We need this bad boy running to terrorize the neighborhood!
