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Hi, car cranks, has spark and pulses ok, crank and cam sensor signal ok. No fuel pulse with noid lights plugged in.
Car was running after head replacement. Would run fine until switched of hot, then no restart.
Got progressively worse from there until now no start at all.
Igition Key antenna is working, but have not checked key chip yet, tester for this in transit. I am leaning towards security/anti theft issue.
Could someone get me back on track with a diagnostic plan.
Previous mechanic tried used ecu, immobiliser and key from wreck.
This has now been in my yard for over a year and i am determined to get this running.
No security light on. Car actually ran (poorly, very rich, black smoke). Today access i drove it around the block.
Plenty of spark, must have been firing injectors as was running. Once warm up, no injector pulse, no run except with external fuel dorce (engine starter in a van).
Will scope crank and cam sensors in morning.
I swapped to spare ecu and security light started flashing and stayed flashing, no pulse on injector, sparked ok.
Cam sensor is brand new, crank is as well i believe.
Without being familiar with that engine, I'd be looking at the cam sensor first. Seeing as you seem to have good spark all the time, that's a good indication the crank sensor is probably okay. Heat can cause intermittent cam or crank sensor faults when the sensors are hot. If the CAM sensor is failing when hot, the PCM won't know where in the 720 degrees of rotation the engine is and potentially won't fire the injectors.
As for the rich condition, maybe look at the fuel pressure regulator. There could be an internal leak. Check the fuel pressure regulator vacuum hose for any sign of fuel in there (there shouldn't be). Also, check your fuel trims with a scan tool. Negative numbers on LTFT and STFT would indicate the PCM is trying to take fuel away. Positive numbers would mean the PCM is adding fuel. Look at your upstream O2 sensor to ensure it's reading rich with a rich condition (probably somewhere up around 800mv or so). If the upstream O2 is reading lean (under 450mv) and never switching to rich, it could be a wiring problem or the O2 sensor itself. NOTE: if the upstream O2 is reading lean, that could mean the O2 sensor or wiring is causing a rich condition, however if it is reading rich with a rich condition, that indicates the O2 is okay. Make sure you're warmed up in closed loop. If it's in open loop, the PCM won't use O2 data to control fuel trim.
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