Contour Enthusiasts Group Archives Forums General Troubleshooting Another noise question...

Ok I cleaned out my UIM/LIM and now I have this weird noise that seems to come from the intake manifold (IM).

My process of cleaning the IM was the same as everything posted on the forums. I went through the full disassembly of the intake. I used B12 spray to clean out the UIM/LIM and for the real gunk I used a wire brush as well as an old tooth brush to get in small areas. Rinsed everything and used a vaccum cleaner on the LIM to make sure nothing fell down that wasn't supposed to. Reassembled everything with new gaskets on the UIM and TB and torque the intake bolts to spec and did it in the correct sequence.

The car runs great now, however on the initial start up I hear a rattle that sounds like metal on metal whirling about in the IM. This sound only occurs on startup. If I turn the car off and then restart it right away sometimes it won't do it, but the majority of the time it does. So you could say if you start and stop your engine and repeat this like 5 times in my case the sound happens 4 out of 5 startups.

I disassemblied the IM to see if anything was lodged in the MAF screen or the TB, but there wasn't anything. Any ideas? It sounds like its coming from the back side of the IM.