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Electronicals / Forscan Expert
Joined: Fri Nov 24th, 2017
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- Cleaned the throttle body. I did this previously with it in the vehicle so I took it completely out and cleaned it again. Wasn't much carbon.
- Took coil packs off and clean the "grounding plate". Very corroded but I don't believe this really does anything but figured what the hell.
- Remove MAF sensor just to look at it and it is spotless.
- Tested fuel injectors using an injector timer and fuel pressure gauge (injector timer does 100 pulses at 3.5ms pulsewidths). Was able to get to injector 1,2, and 4 connectors and all 3 of those dropped from 63 psi to 52 psi when pulsed using the timer. So they all have the same flow rate.
As it stands right now I'm thinking it's one of a few things:
- Something sticking in the head (like a valve).
- Possible a coil pack cross firing?
- Something killing the ignition or fuel timing. Drop in crank or cam sensor.
I'm starting to pull away from the valve train just because it will flat out stall after a high rev or after wide open throttle and let off. I feel if a valve was sticking it would still run off losing a cylinder. To me the stalling would be more of something that affects all cylinders.
Would this be a crankshaft sensor issue? I know these use a 2 wire sensor so the signal frequency and the voltage amplitude increases with speed. I'm wondering if it is dropping out or shorting out just a hair? Looks like the sensor is behind the water pump inlet tube and you have to remove it to get to the sensor.
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2000 XLT 2.5L A/T 2WD
Mods:
Power Windows/Locks Mirrors using OEM harness and parts
Explorer Sportrac White Face Cluster
Explorer OHC and Auto-dim Mirror
Auto Door Locks
Full HID Projector Retrofit