Vibrations and bad sound after coolant Pipe Replacement

[cesarblanco]

Hello, after coolant pipe replacement in a S V8 the engine sounds like this and I can feel small vibrations. I would appreciate any advice.

Regards

César

Edited March 30, 2014 by Loren

[RFM]

The only thing that can affect the engine behavior, after replacing the plastic cooling pipes, is a leaking intake manifold gasket, a leak in the thin plastic tubes into the V of the engine or a small leak somewhere between both MAF and the manifold. If the CEL is not lit, is it still advisable using a diagnostic device, such as PIWIS, to check the engine actual values.

[cesarblanco]

Thank you very much for your support, RFM, I appreciated a lot your help.

I have removed the manifold to install it again very carefully (with new gaskets). In addition to that I will check the other two points you mentioned as possible origin of the problem. The thin plastic tubes into the V of the engine is this coolant vent line (94810601693) Picture 1? And the small leak somewhere between both MAF and the manifold could be in this part (Picture 2)?

Thank you

César

Edited March 31, 2014 by cesarblanco

[PKN]

Also check under the Y air intake. It is very easy to get the vacuum connection under there to hit the fan.....

Steve

[RFM]

So as to see and hear on your movie, it can be only a small detail. It is not that one of the cylinders is missing or so, therefor the engine does not shake enough. Check all the specified items, including the theottle/manifold connection. If you cant see anything, use a PIWIS or similar diagnostic tool to find out whats wrong.

[cesarblanco]

PROBLEM SOLVED.

Thank you for all responses. After reinstall the manifold very carefully with the help of a friend, now everything seems to work OK. In my first installation, with no help, probably the gasket at the rear side was bent slightly.

Here the engine with the new sound:

https://www.youtube.com/watch?v=PjOowlPzDoQ

Thank you for your support!

[RFM]

Properly resolved.