95 Tracker engine noise on acceleration

I had a stalling problem which I diagnosed as a sticking EGR valve. I replaced the valve and the stalling issue seems to be corrected (it was intermittent so I'm not 100% sure yet). After replacing the valve, I get a heavy buzzing noise on acceleration that I'm pretty sure wasn't there before. It seems to start just before the regular sound of the revvnig engine as I depress the accelerator. I've tried checking the hose connections to make sure they are secure but I haven't vacuum tested anything yet. Just to eliminate the easy stuff I replaced the air filter, checked/gapped the spark plugs, used a fuel injection additive, adjusted the idle speed and set the timing. But the noise persists. It gets worse with more rpms but it doesn't seem to effect performance that much...there may be a slight loss of power.

Has anyone seen this before or have any clues as to what to do next? Any help will be appreciated Thanks.

I had a stalling problem which I diagnosed as a sticking EGR valve. I replaced the valve and the stalling issue seems to be corrected (it was intermittent so I'm not 100% sure yet). After replacing the valve, I get a heavy buzzing noise on acceleration that I'm pretty sure wasn't there before. It seems to start just before the regular sound of the revvnig engine as I depress the accelerator. I've tried checking the hose connections to make sure they are secure but I haven't vacuum tested anything yet. Just to eliminate the easy stuff I replaced the air filter, checked/gapped the spark plugs, used a fuel injection additive, adjusted the idle speed and set the timing. But the noise persists. It gets worse with more rpms but it doesn't seem to effect performance that much...there may be a slight loss of power.

Has anyone seen this before or have any clues as to what to do next? Any help will be appreciated Thanks.
where abouts is the noise coming from?

I wish I knew. It's coming from the engine but I can't tell exactly where. The buzz seems to be related to the EGR valve replacement. I actually removed/cleaned the old EGR valve and when I re-installed it I first heard the buzz...only it only happened at higher rpms during acceleration. I decided to replace the valve with a new one and after that...the buzz was slightly worse in that it started at lower rpms. Thanks.