Hey everyone,

I recently noticed that when my V8V reaches about 3K RPM there is a high-pitched harmonic resonance/buzz that appears to eminate from the front dash/steering column/speedometer area. I'm usually in first or second gear when I notice the sound...and only in residential and city driving (not on the highway). If I get the RPMs up to just over 4K and then take my foot off the pedal, I can also here the sound as the RPMs come down between 3K and 4K RPM.

Has anyone here ever experienced or dealt with this issue?

In terms of recent changes/updates to my car, I had the AM Sports exhaust system installed about 3 weeks ago and also had my windshield replaced at the same time (all done at my local AM dealer).

Immediately after is when I began to notice the high-pitched harmonic resonance/buzz I desribed earlier, as well as a bunch of squeaking/rattling coming from the front vent areas.

My sense is that when the windshield was removed, something got knocked out of place to cause all the squeaking/rattling along the vents.

However, in terms of the high-pitched harmonic resonance/buzz, I don't think that's necessarily because of the windshield replacement. I sounds more like a heat shield issue from the research I've done. Maybe related to the exhaust that was installed? But, the exhaust upgrade was only to the muffler located in the back of the car, so I'm not sure that is the cause

My car is obviously going back to the dealer next week, but I just wanted to get any thoughts from the forum in the meantime....

 

I have heard two things that may cause this,
1: The heatsheild at the rear of the car can rub on the subframe causing a really loud buzz.
2: I have seen the vin plate on the windsheild touch and cause the same buzz noise.

 

Thanks AMFixer - I will have my dealer take a look at these two areas.

 

The screws that hold down the vents near the base of the windshield used to loosen on my V8V. I had to tighten them every month or so or the vents would vibrate and give off a high frequency noise. I was planning to use some Loctite on them, but traded in the car before I had an opportunity to try it.

 

The constant (and very annoying) squeaking that I am now hearing all the time seems to be related to a bum install job on the windshield. My dealer keeps insisting that the installation was done correctly, but after I showed them my fix to the squeaking (see pic below), I think they might have to concede that the windshield was not set properly. Seems to make total sense as this squeaking only start AFTER the windshield was replaced.

I spoke to a windshield installer who explained that the windshield actualy floats on a layer of urethane glue. Sometimes, if you add too much or too little, it affects the height at which the glass floats on the car frame and in my case, it looks like its sitting too close to the plastic vent area (i.e., too little urethan was applied).

The trick now is trying to figure out how to wedge something in between the glass and the front vent without (i) replacing the entire windshield or (ii) removing the whole dash.

I'm leaning towards having them replace the windshield as I fear removing the dash will need to a host of other problems....such a mess (something I expected to aviod by going through my local AM dealer).

 

Do NOT drop the dash. I agree that you would be asking for trouble.