slvr05vette

Need some help. I have an 05 corvette and recently removed the intake manifold to replace a failed oil sender unit. After installing a new oil sender unit I re-installed everything but now have a check engine light and a P0300 code indicating random/multiple engine misfire. The engine is idleing very rough and the exhaust has a strong fuel odor. I double checked all injector,and spark plug wires and they are all secure. What could be causing the engine to misfire and the strong fuel smell? Any advice would be appreciated, thanks!

bobeast

The fuel smell is probably just a symptom of the misfire. i.e. if gas is not getting burned in one or more cylinders, then that fuel has to go somewhere. You said the engine is running very rough. You might try pulling the plug wires one at a time. The pull that does NOT change the roughness is likely the cylinder that is not firing.

See if you are getting spark from that plug, and work backwards from there.

SUB VETTE

Vacuum leak?

0Jared@RPP

Possible you have pinched an intake gasket? Causing a vacuum leak on one or more cylinders which will set a misfire code.

erick_e

The fuel rail and injectors may not be fully seated. I had a similar issue when my injector o-rings were damaged.

slvr05vette

had the car checked out by a mechanic and he stated that I'm getting no compression in cylinder #1! why would I be getting no compression after just removing and reinstalling the intake manifold?

erick_e

Manifold gasket probably isn't sealing, allowing the cylinder pressure to escape back into the manifold.

slvr05vette

Yeah I probably should have mentioned that I broke one of the intake manifold bolts while tightening down the manifold. Bolt #1 was over tightened and broke. Could this possibly be the cause for the compression?

JakeC6Racing

+1 on this. Installed a Boss 302 manifold on my 5.0 and one of the o-rings on a fuel injector had fallen off during the switch and caused a misfire.

tennblkc6

yes..most likely. did you repair it after you broke it?

slvr05vette

No I didn't repair the bolt I just made sure to tighten all the other bolts correctly. I got 44 lbs-inches mixed for lbs-ft.

SUB VETTE

You going to have to replace that broken bolt to get a good seal.