Over the last few week my car has developed a few new rattles and clicks that range from mildly unsettling to maddening. The first is more unnerving that anything else, and is very recent. Basically upon startup when the engines coldit will start right up I will hear this rapid clicking noise from the engine bay. It will click 10 times or so then fade away, not to be heard again until the next time I start it up cold. I can't seem to lock down where its coming from.
The second one is the maddening one. At first I thought it was engine pinging, and i haven't ruled it out, but its hard to know what the pinging could be coming from. The engine has stock compression, is running at about 12 degrees BTDC and has nothing aggressive done to the engine. Its also running in a pretty decent state of tune. So thats why I have ruled out pinging, for the time being. It may just be an exhaust rattle of some sort. Its a loud, high pitched rattle that only occurs in the upper rpms and when I get on it. It *seemed* to happen more under load, but it also happens when I'm on flat roads and while goind downhill as well. It sounds like its coming from the area where the motor meets the transmission, but its hard to isolate since I only hear it while driving (haven't been able to get it to happen while sitting in the garage and revving it, yet). It also seems to reflect off walls and such... when I drive next a wall on my left, the sound will seem to come predominantly from my left, etc.
Any ideas? While I'm certainly okay with most rattles and such, both these sounds have me a bit concerned...
The second one is the maddening one. At first I thought it was engine pinging, and i haven't ruled it out, but its hard to know what the pinging could be coming from. The engine has stock compression, is running at about 12 degrees BTDC and has nothing aggressive done to the engine. Its also running in a pretty decent state of tune. So thats why I have ruled out pinging, for the time being. It may just be an exhaust rattle of some sort. Its a loud, high pitched rattle that only occurs in the upper rpms and when I get on it. It *seemed* to happen more under load, but it also happens when I'm on flat roads and while goind downhill as well. It sounds like its coming from the area where the motor meets the transmission, but its hard to isolate since I only hear it while driving (haven't been able to get it to happen while sitting in the garage and revving it, yet). It also seems to reflect off walls and such... when I drive next a wall on my left, the sound will seem to come predominantly from my left, etc.
Any ideas? While I'm certainly okay with most rattles and such, both these sounds have me a bit concerned...