When I'm idling at a stop light, clutch in, I get this weird ping sound every 30 seconds or so. It sounds like a rock is falling on my hood or something. For some reason it only happens when I'm in the car on the road because I never hear it when I'm standing in front of the car with the hood up. It runs fine when accelerating (except for a secondary boost leak).

This may just be my imagination, but I think the noise started after I changed the plugs and put in a thing of techron.

Anybody have any ideas what it might be?

 

Are your plug wires hooked up correctly? This would make your car consistently run bad, but it's worth a shot.

 

I'm pretty sure they're hooked up correctly, I did the plugs one-by-one. Also its much smoother overall. Just this damn pinging.

One thing that may be related is that my ABS warning light is on since I had some electrical trouble. Maybe my brakes are making weird noises...