Replacing Head Gasket: parts list
#16
FloppyJoe - NPI is short for non-power improved. These were the early heads that Ford put on the 4.6/5.4 engines. They have larger combustion chambers (I've seen 49-51 ccs listed) and they don't flow as well.
The PI heads, Power Improved, have a smaller combustion chamber (42 ccs) and flow better.
So 1/2 your engine has lower compression and poorer intake/exhaust flow, so it won't perform as well as the other 1/2 of your engine.
Something definitely went wrong at Ford when you took it in. Either it was intentional or maybe the Tech got the heads confused between yours and another head that was off for service???????????
The PI heads, Power Improved, have a smaller combustion chamber (42 ccs) and flow better.
So 1/2 your engine has lower compression and poorer intake/exhaust flow, so it won't perform as well as the other 1/2 of your engine.
Something definitely went wrong at Ford when you took it in. Either it was intentional or maybe the Tech got the heads confused between yours and another head that was off for service???????????
#18
It seems like it might be tough to prove that Ford put the wrong kind of head on your engine, especially since you just took the engine apart.
I can't give you any guidance on long term damage, it certainly can't be good. There are variations in output among cylinders in every engine, but that variance has to be much smaller than what is going on with your eninge.
I can't give you any guidance on long term damage, it certainly can't be good. There are variations in output among cylinders in every engine, but that variance has to be much smaller than what is going on with your eninge.
#20
I'm sure they knew they what they were doing. I remember it took them like 3 weeks to do the job. They probably couldn't get the proper head in so they just threw some old one in there even though it didn't match. They prolly figured I'd never find out. I'm so pissed off. These bastards will pay for this.
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#25
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Simple stuff first. Is every connector pluged in? Look closely at the camshaft position sensor as well as the crankshaft position sensor. Did you trip the fuel shutoff valve? Id the TPS adjuated properly? If the PCM sees an off idle postion it could flood the engine. Try unpluging it if the rest checks out.
JMC
JMC
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