I JUST PURCHASED A 1983 Z-28 WITH THE CROSSFIRE INJECTION AND WHEN I GIVE IT MORE THEN ABOUT 1/3 TO 1/2 PADLE IT SPUTTERS REALLY BAD AND HAS A REAL BAD FUEL SMELL AND BACK FIRES SOME TIMES. BUT IT SEEMS LIKE WHEN I FIRST START IT AND GO IT RUNS FINE. I HAVE CHANGE CAP, ROTOR, PLUGS, WIRE, INJECTOR CLEANER, AND AJUSTED THE TIMING TO 6 DEGREES ADVANCE ANY IDEAS WHY IT RUNS THAT WAY.

 

what about fuel filter? Do a search on the TBI board.

also http://www.crossfire.homeip.net/

 

First welcome to the board.I agree about the fuel filter.Mine did that when I first got her.I did a full tune up but forgot the fuel filter...duh.I changed that out and it improved but she had been sitting for a long time so I added some fuel stabilizer and after a couple tanks of gas and another new filter she runs good now.The one thing I haven't done is change the filters that are one each injector.Also when you set your timing did you put the ESC in bypass by disconnecting the black/tan wire?It's a single wire connector at the rear of the passenger side valve cover.
And thankyou phess I had forgotten to save that link.

 

Something else I found on my '83 I just thought of.When you change the filter check the fuel line feeding up to the front TBI unit. The line on mine was kinked where it passes under the alternator bracket.This is similar to what happens to fuel lines on quadrajet carbs when 2 line wrenchs aren't used to loosen the lines.She was being fuel starved under load.I was just going to replace the line but thought it would be better to modify the fuel inlet setup to move the filter away from the heat of the exhaust manifold/block.Just another idea to try.