so when i revv up my GTA too like...4 or 5k it shoots out this black powder stuff but its kinda moist and oil like...stained my parents drive way too oops...so what could it be? maybe to rich??

 

Most likely soot from an overly rich condition.

 

i forgot about this thread
anyway..so do i just get it retuned?

 

Datalogging would be the first thing you should do.
You need to see what your BLM's, INT's, and O2 sensor are reading.

 

how would i go about doing that?

 

Get ahold of Dyno Don and let him data log your car.

 

Some is completely normal, especially if the car has been sitting and theres still a fair bit of water coming out the exhaust from condensation.

 

should water always be coming out??

 

Mine does most of the time when cool.

 

My '86 Plymouth does that when the choke gets stuck, more fuel than air.

 

Part of the composition of the exhaust is water, usually there is more on a vehicle with a cat.

 

Staining of the driveway usually indicates a rich condition.
I actually had to use gas on my garage floor to clean up my mess. I found that all 8 of my injectors were stuck open.
I guess there's a legitimate reason for the washers that go between the fuel rail and bigmouth intake.

 

bad knock sensor, it controls the timing especally over 4k

 

hmm...alright. what about the o2 sensor??

 

make sure your injectors don't leak, is it misfiring?

 

Had exactly the same problem with mine when I bought it, I was getting 8 miles per gallon too LOL.. i've still got the stains on my garage wall!

Could be a rusty old muffler, give it a shake if it rattles, replace it.. but most probably a high rich condition, so plugs, distributor rotor and cap, with wires are usually suspect.. start with the plugs.. I'd also check the resistance over the fuel injectors, they should all be the same.. and check the o2 sensor, which will put the computer in open loop if it thinks the sensor is lying to it.

There's a great vid on youtube for testing an o2 sensor
http://www.youtube.com/watch?v=vdn4Dk5PSwc

How quickly does it come up to temperature? an excessively rich A/F condition made my iroc-z hover around 110deg forever..

 

ok...i was gonna change my plugs soon anyways.
and no it gets to 190 and chills there...