clunking noise when starting HHR.
 

I hear a clunking noise when I start the bugger. Just had an oil change done a couple days ago and this noise started. Only at start-up, hear it once and that is it. It sounds like something is just loose or not clipped.

I have to be honest- I haven't fiddled around with the engine since I bought it two years ago (I guess that is a testament to how well it has run). I have tried to locate the sound but to no avail.

Here is a couple quick q: is the air box supposed to 'float' on top of the engine? The whole plastic panel is loose. Again, never touched it before now so I have clue if that is how it is supposed to be. I think it might be what is making the noise, but I can't find anywhere that it ties down at.

did you change the oil or did you have it done if you had it done couple possibilities are they forgot to tighten the drain plug and now you are low or out of oil or they used the wrong oil

It could be that the cover over the motor is not snapped into its mounts and something moves with the first vacuum generated at start-up. The cover should not be loose. Check by feeling the two snap-in mounts at the back of the air box. Is the box firm at both of these points? Then check one more snap-in point on the passenger side at the front of the box.

Is it possible to start these motors with the hood up? If not you could fool the hood switch into responding as if the hood was down. Anyway, having someone start the motor whilst observing the engine compartment might give some clues.

Hey, thanks for the response. Yep- the plastic cover wasn't snapped into the rear mounts. I reset it and no more clunk. Thanks!