94 f 150
302 V8, changed the plugs and wires, distributor and rotor, but it is not firing on two plugs, what's the problem?
You didn't mention that you replaced the cap, it could have a carbon track that is pulling spark energy away from those two cylinders.
If it is just not firing on two plugs,it may be bad wire,or the tpi is bad,if these are not the issue,you may need to check the compression on the two cylinders that is not firing.
All so agree with tennisshoes.
Thanks for the responses, yes new cap, changed wires on non-firing plugs, still not firing, changed plugs on non-firing cyclinders, still no fire. The problem plugs are the two cylinders second from front on each side.
Terry have you took a spare plug and removed the wire from engine and stuck plug in it and turned engine to see fire?
Your not firing on 2 and 6,they are side by side in the distributor cap,
But the bad news is the fire on the same piston,meaning you might have bad valves on it.
Double check the firing order if you actually have spark at the plugs.
Thanks once again for all possible solutions. Will try to get all relevant history into question this time. truck sat for two years, engine has less than 25 thou on it. yes double checked firing order, no fire on those two pulled plugs against block.put fuel injector cleaner in gas tank, I have considered sticky valves because of sitting and I will drive to store in town to get some sticking valve stuff, and see how that works. I also considered maybe timing off?
You indicated you were not getting spark on the two cylinders when grounded against the block. OK. Get a HEI spark detector (about fifteen bucks) and verify on those two cylinders. If still no spark, the problem is somewhere from the wire back to the distributor.
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