tjohnson07

I have a 2002 Camaro Z28 with a 6.0 LQ9 motor. I am getting a code for multiple cylinder misfire. The car idles weak and fluctuates rpms with clutch and brake pushed in while coming to a stop from around 800-1200. The rpms level out when at a complete stop. The car is also hard to get into gear sometimes. I have changed plugs with Tr5ix and got new accel plug wires. I also changed the fuel filter. Any other ideas greatly appreciated.

Mercier

iTrader: (15)

Clean your MAF, IAC(if equipped). Check for vacuum leaks. Have you ruled out bad gas? Checked your fuel pressure? How does it run at higher RPM/load?

tjohnson07

Cleaned maf and iac. No vacuum leaks and a fuel pressure of 55.

Mercier

iTrader: (15)

How does it run outside of idle and under load? Have you ruled out bad gas? Have you checked your grounds?

dogger

iTrader: (1)

Are you running the stock Lq4 fuel rail? If so dirt gets into the end of the fuel rail at the number 7 cyclinder and builds up til it falls into the number 7 injector. Causes a random misfire at light medium loads. Clean the fuel rail and have the injectors clean and balanced to make sure they are good.

Mercier

iTrader: (15)

Dogger, that's interesting. Is that only the LQ4 rail and why? Or is it truck rails in general?

Thanks.