First I noticed my Z was sounding like it was putting a little last week. Wasnt sure because I havent driven it in a few weeks and maybe I was hearing things. Then a friend mentioned it sounded different too out of the blue. Then today it was really noticable. The difference sounds like someone took of the air box on a stock car. Z is still boosting but Im not sure where to start looking.

Im thinking an IC pipe might be loose. Possible a crack in the headers (they are Stillen and it sounds like its coming from there). Also, what should my boost guage read when car is off, key is in and still off and when its started? Thanks for any insight.

 

does the engine sound off for example bad plugs.. different exhaust note or you have "extra noise" rattle or leak of some kind?

 

No rattling sound. Different exhaust note but more like its soming from the intake. The plugs should be ok. Changed them about 8 months ago and don't pile the miles on my Z. But I have been running rich for some time now.

 

do a compression test.. make sure all your cylinders are working properly? if you think its intake related check those pipes and clamps

 

Just took off the blower belt and it still doesnt sound right. Sounds like the intake has a deeper throatier sound.

 

How do you run a compression test?

 

get a comp tester, heres a little info i found quick, oil and coolant looking good?

http://www.aa1car.com/library/compression.htm

 

Dropping it off at Dr Todds in the morning for some diagnostics. Also if everything is ok he's going to tune for the 2.87 pully.

 

I think its the blow off valve. Had my wife give it gas while I had my hand on it. I think its supposed to close when you give it gas. It stays open.

 

Also check for exhaust leak. This could make the car suddenly louder as well...

 

well good luck hope its something minor!!

 

Got under the car to swap the bov and saw my HFC was cracked right on the weld.