92 Z28 LS-1

iTrader: (1)

I installed a comp xer273 (224/230 .581/.592) and it has poor throttle response at idle but great at about 3500. I installed a wideband today and the idle AFR was 19.9 and at 4000 it was 14.0. I assumed the car was rich and flooding at idle but it seems exactly opposite. Any ideas?

PS Ordered HPTuners should be here this week.

Alvin

iTrader: (2)

Don't put 100% confidence in your wideband. You can be so far out or something else might be wrong like a misfire or exhaust leak which will screw up a wideband reading.

92 Z28 LS-1

iTrader: (1)

Thats a good idea, especially since i made my own headers. There very well could be an exhuast leak. Its hard to hear over the cam and chambered mufflers.

2002_Z28_Six_Speed

iTrader: (19)

I opt for exhuast leak! Disable DFCO but I bet that isn't it. The AFR should be far leaner for DFCO. Mine pegs 50 I think.

92 Z28 LS-1

iTrader: (1)

I just moved the wideband sensor to the opposite header and got same readings of 19.8 idle and 14.9 at 4000rpm. Another idea i had was either a miss fire at idle or my car is a 92 camaro still with the stock fuel pump. The stock pump is a 44psi multiport fuel injection pump not an LS1. It worked fine with a stock LS1 so i assumed it would be enough to idle the cam. I got a Walbro 255 pump and HPTuners on the way, so something is going to change.

92 Z28 LS-1

iTrader: (1)

Fixed the problem. It was something pretty stupid. After I put the motor back in I forgot to plug in the alternator energizing wire. The alternator was not charging and the pcm was operating at low voltage. After I pluged in the harness the idle AFR was bouncing around 14.6

2002_Z28_Six_Speed

iTrader: (19)

Anyother victory over the forces of evil --- or the like! Congrats man.