1994 Sable hot start problem

Every second day or so, it takes several cranks to start the car when left hot for half an hour or more. It appears that there is no spark, but since it
always starts it is hard to find the problem. Air bypass valve replaced by Ford as an attempt to fix it, first and last... I replaced coil, ignition module, wires, cap, spark plugs, coolant temp sensor, New fuel pump, filter and battery. Cold start no problem, runs excellent but this hard starting when hot gets me stumped. This started last summer and continues without getting better or worse. Code reader shows nothing. Any ideas? 3.8 engine, 237 000 km.
thanks,
Stan
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What is the evidence? How did you test for spark? Borrow OR buy a cheap timing light and have it ready.
One thing you HAVENT mentioned is adjusting fuel delivery while cranking. What's the effect of pedal to floor; or pumping the accelerator? Pedal to floor will overcome leaky injector syndrome, which is a possibility but not the ONLY cause, which could also be the tps. You also havent mentioned the TPS; unlike the TFI (which only needs serviced), and most other sensors, the TPS IS a wear item and should be replaced if it's the original. Echlin is a good mfr
Another tip: If it's having this fit, turn off key, and disconnect the MAF connector. If it then starts, clean the MAF and see if it reoccurs.
Also if your TPS is flaky then checking driveability without the MAF will point it out. - - - - - - -- - - -- - You've fallen into the worst of traps.
Apparently you've spent well over $750 attempting to solve this.
On the plus side, you might have replaced some of those anyway..
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stig wrote:

Maybe an injector(s) leaking when hot? Then either lack of fuel pressure for a time or a flooding clearing?
Bob
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