P0171/4 Codes - About to torch the car...
Thread Starter
Teching In
Joined: Jun 2015
Posts: 19
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No cats, brand new plugs, and holds 58 psi consistently, fuel pressure regulator was replaced a year ago, but I suppose it could have gone bad already, I do have the truck intake and stock rails with the stock FPR
Thread Starter
Teching In
Joined: Jun 2015
Posts: 19
Likes: 0
Thread Starter
Teching In
Joined: Jun 2015
Posts: 19
Likes: 0
Borrowed an inline spark tester and power probe from work, the signal to the plugs on every cylinder is weak, I checked every wire to the coils, I have good ground, positive and signal to the coils but they're all firing very dim
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TECH Fanatic
Joined: Jun 2014
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I would triple check all my grounds, put a fresh set of plug in, check crank, and cam sensors . Battery up? Needs 12v while cranking to start. Check ecm power wire for 12v while cranking. This happens a lot , batt gets run down . Will crank, but ecm not getting enough juice
Codes P0171/4 Got a real head scratcher there. Car ran fine, then acted up, then would not start. At some point thru codes P0171/4. Noid light confirms injectors working, pressure at the rail is 58 PSI and plugs are firing but weak. Could this be a broken ground wire that still has the cover on it? Is the engine grounded? Have you tried starter fluid? Just before it quit did you do any work on it? If it won't run with starter fluid then the focus should be on spark. Let us know what you find please.
Thread Starter
Teching In
Joined: Jun 2015
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figured it all out... you're not going to believe this ****...
So when i took the intake manifold off to replace the gaskets, I decided to clean it while i was waiting for the gaskets to arrive. After spraying it and scrubbing it i set it off to the side on the garage floor to dry, while it was sitting there for a week or so, a mouse decided to make a nest inside it out of papertowels and such that were in the garage, when I got back to working on the car I installed the intake and buttoned everything up and tried to start it... The paper towels sucked against the intake valves and partially through causing zero compression on all cylinders, ended up slightly bending one.
pulled the head so when the gasket, valve and head bolts come ill hopefully finally get it running after 7 months... just in time to put it away in storage
So when i took the intake manifold off to replace the gaskets, I decided to clean it while i was waiting for the gaskets to arrive. After spraying it and scrubbing it i set it off to the side on the garage floor to dry, while it was sitting there for a week or so, a mouse decided to make a nest inside it out of papertowels and such that were in the garage, when I got back to working on the car I installed the intake and buttoned everything up and tried to start it... The paper towels sucked against the intake valves and partially through causing zero compression on all cylinders, ended up slightly bending one.
pulled the head so when the gasket, valve and head bolts come ill hopefully finally get it running after 7 months... just in time to put it away in storage
