ChrisMitchell

2000 a6 2.7

I just changed the Auxiliary water pump, so I had to take the intake manifold off. And after putting everything back together I had multiple misfire code. And actually the car lost power while driving and started shaking. Its all good though, got a tow and it still drives.

Bolts are tight.
Spark plugs are good.
coils should be fine but I can try changing them.
Cannot think of anything else though, and this started immediately after the job, so I really dont think coils will do it.
Any ideas?

georgeb944

Probably a vacuum leak due to a misaligned intake manifold gasket.

If you can, do a boost leak test (google for DIY boost leak tester) or smoke test (if you have that available.

Of course, it could be an electrical connection that you have missed, etc.

ChrisMitchell

Thanks a lot. If I need to realign the manifold do I need new gaskets?

georgeb944

If the gaskets are damaged, then, yes, you will need new gaskets.

The purpose of the gasket is to completely seal the intake manifold from air leakage into or out of the area. If the gasket is bent, torn, rippled, or otherwise damaged, it will not do its job.