OT; need help with LT1 motor
 

I know someone on the board knows the LT1 very well. I just cant remember who it was .

The wife's car is running rich. its a 93 Firebird Formula, the tail pipes are turning black and it blows black smoke when you get on it. it also back fired once when I let back on the pedal after running it hard. It don't seem to have the low end power it should. I will drive the car and feel it load up. so I will put it in neutral and rev the hell out of it to blow it out and then she will run smoother.

this is what is done to the car.

BBK headers, no cats, and BBK pipes and muffler. ( she is load)
pullies
stage 2 chip
160 thermostat
K&N filter and pipe to intake.
That thing that goes in the throttle body.

I just changed the distributor & plug wires 2 months ago , it also has Bosh triple platinum plugs installed 10k mi. ago. The O2 sensors were changed about the same time. but this was all prior to the installation of the chip and K&N intake set up.


Also this car is an automatic. :( ( the price was right )

Thanks

Paul :)

Is it putting out any codes?
Gary

try checking the EGR or the IAC

no check engine light

would any of these give me a check engine light?? and what do they do ???

SELL IT and buy a CHEVY truck!:p :p :p

my mom has a 2k firebird, auto too, if only she would put 2k into it, it would fly.

Intake
Exhaust
Throttlebody
Mass Air Flow Sensor
Intercooler Lid

They may or may not. First try the easy stuff. Get some carb cleaner and a toothbrush and clean the throttle body. I thought the 93s were port injection?
Anyway, the IAC controls idle speed. Clean it or replace it (about $35). The car would probably idle poorly if it were bad.
The egr valve and control solenoid/valve adds exhaust to intake to increase exhaust temps, lowers NOX. It should close under throttle after engine is warm. May be carbon fouled. Clean it, check for correct operation.
I assume your chip maker reccomended the 160 degree thermostat with the chip.
O2 sensor was a good thing to change. You also might check the engene temp SENSOR. Not the sender for the guage. If it's off or there is excessive resistance in the connecteion, the computer may think the car is still warming up and stay in open loop operation. That's especially true with the 160 thermostat.
My $0.02
Gary

As Gary said it may or may not set off codes......i remember a GM tech telling me they had a tech bullitin for the 4.3 engine EGR valve where they had to reflash the computer and have the EGR "bounce" so to speak to keep its self clean!

You may want to check this site to see what if any TSB's there may be on that particular engine...

http://www.alldata.com/recalls/index.html

Mopar sells some stuff called Combustion Chamber Cleaner.....its in a spray can and works well! I used it on my jeep that has 116k miles. Its about $8 and you spray it down the throttlebody into the running engine...then turn the engine off and let it work for about 5min.....start it back up and drive it off.....will smoke for a bit but it goes away.

Check the temperture sensor. I had a Chevy pick-up that left black soot on the driveway. Turns out it was the plug that goes to the temp sensor. It was corroded so it was always reading cold engine. It was hard to start and when it did it was rough and blew black smoke.