Today my mechanic installed some Senki Revo Sport headers on my 2002 Honda Accord SE, however, i knew something was wrong the second i pulled out of the parking lot, as i accelerated, i heard a weird whistling noise coming from the engine bay, along with the distinct smell of burning, i got out and checked to see what it was and everything seemed fine, i drove back to my mechanic and told him about the problem, but he said that's the way it was supposed to sound, i think that's a load of bull. So im guessing that there's a leak somewhere, any opinions on what it could be?

Edit: On further inspection, it kind of sounds like its coming from under the bottom of the car, so now i think it still might be a leak, a crappy welding job or the test pipe is cracked.

 

If you don't see a leak - theres a good chance its probably coming from the corrugated wall in the flex. If theres no flex in the header its from a poorly mated pipe merge or weld joint.

 

did you check all the bolts and make sure everything is still tight?

 

Checked all the bolts and everything is solid. I checked the flex pipe out, and the whistle isn't there either, checked the O2 sensors, there tight on there as well. I can't find any signs of leaks anywhere. i get the "whistle" around 2000 to 3500RPM and going, any ideas what it might be, also, i checked welds, no cracks from what i could see.