ok i have a 93 z28 and i have the hot cam kit and ported heads. my exaust smells very rich and im getting a black build up on my tips. i have the stock injectors with a stock power chip so will this make my car barely want to idel and some times die? but when take off and run it it does ok and makes ok power just wont idel i ran a 13.6 with a 2.73 rear end and poor 60' times. any help would be great.. what should i do were should i start.. my little bro wants to drive this car to his high school dance so any fast help would be great thank you very much

sorry about the spelling and grammer

 

Sounds like the car has never been tuned for the mods, get the PCM tuned.

 

is that the only thing i can do or wht else can i look at??

 

If you have high mileage on your O2 sensors, that will tend to make the car run rich also. Also pull the vacuum line off the fuel pressure regulator and see if any gas comes out. A defective fuel pressure regulator can cause gas to enter the intake via that vacuum line (there shouldn't be any gas there). Also check your fuel pressure by attaching a fuel pressure gauge to the Schrader valve on your fuel rail. Your fuel pressure at idle, with the vacuum line pulled off the fuel pressure regulator, should be 41 - 47 psi.

 

Check the accuracy of the MAP and IAT sensors. If they are "off" in a speed-density setup, it will screw things up quite a bit.

 

The other sensor to check is the coolant temp sensor in the waterpump. A troubleshooting guide from Shoebox's site: http://shbox.com/1/4th_gen_tech2.html#ect