Misfiring and 2 spark plugs keep backing out?

2007 CHEVROLET SILVERADO
200,000 MILES • 5.3L • V8 • 4WD • AUTOMATIC
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WANDAANDBUDDY
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  • 14 POSTS
The truck listed above is a classic 4wd. still has a misfire after changing plugs and wires. There is an exhaust leak at manifold and 2-3 bolts need to be replaced on manifold due to being loose or broken off. Fuel filler neck has leaked also. Fuel pressure is good coming from the Shrader valve under hood. The cats were removed and pipe replaced cats. I have O2 adapter things inserted to kind of take place of converters being removed. Truck still misfires and won't go. After flooring it, it usually has little acceleration and then takes off like a rocket. Then loses acceleration again. Could this be coil packs bad or injectors clogged up? Or could it be trash in tank since filler hose is leaking? Tried everything. Tired of working on it. Need help bad.
Oct 17, 2024 at 4:21 AM
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STRAILER
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It kind of sounds like you have a weak fuel pump, but can I ask if there are any trouble codes?

This guide can help:

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

I can tell you an exhaust leak is not good because it allows air to enter the exhaust in which case the PCM will richen the fuel intake of the engine up. Also, I would do a compression test to make sure the engine is not hurt.

https://www.2carpros.com/articles/how-to-test-engine-compression

Please go over these guides and get back to us.

Oct 17, 2024 at 4:44 PM
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