You will need to find a way to scope the crankshaft position sensor as well as the ignition and fuel injector signals on this misfire condition. Anything else is guesswork.
p0300 2000 chevy 5.3
have a 2000 Silverado with a 5.3 and have a p0300. cylinders 1 & 8 are dead misfires at idle but when you get the rpms up the misfire moves and starts jumping around to all cylinders. have new plug wires and plugs have also had the injectors test and cleaned. tested wires from ecm to each injectors wire and they are good. have swap coils from cylinders. 1&8 are still dead till you get high in rpms then it moves to multiple cylinders. did a crankshaft and camshaft sensors and timing gear and chain. and i still have the dead cylinders on 1&8 till i get high in rpms then it moves to other cylinders and did a compression test on the motor have 150psi across all cylinders. pretty stumped any info or recommendations would be extremely helpful tired of throwing parts at it and nothing working.
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My case is different though.
I have 48 psi on my 2001 5.3L on my 2nd 150k miles tired fuel pump and still runs fine. It does not bleed off though when turned off.
Still runs very good at 309k miles.
There must be other causes of your misfires.
I have 48 psi on my 2001 5.3L on my 2nd 150k miles tired fuel pump and still runs fine. It does not bleed off though when turned off.
Still runs very good at 309k miles.
There must be other causes of your misfires.
Instead of pulling fuel rails, swapping injectors, then installing the fuel rails back to test, why not just pull the fuel rails with the injectors in place, lay it on top of engine with injectors visible, prime the fuel pump and observe if injector is leaking causing drop in fuel pressure. Fuel pressure gauge must be hooked up.
I already suggested that but I guess not everybody has access and know how to use and interpret signal value and synch.
You will need to find a way to scope the crankshaft position sensor as well as the ignition and fuel injector signals on this misfire condition. Anything else is guesswork.
1 - 4 of 26 Posts
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