Rep Power: 0

Hi,

Was hoping someone could help with a major problem.

I have a 1.6i LS Coupe D16Y7 70k miles. The car runs great and has good fuel economy, BUT its running rich. On the tests running higher than legal CO & NOX.

I have replaced the manifold catalyst and the lambda sensor at great expense, but that only brought the readings down slightly, so a contributor but not the cause. I also replaced all the plugs and air filter. Cleaned the throttle body & IACV, helped to control idling surge.

One thing we noticed that doesnt seem right is that cylinder 3 plug is running black all the others are okay.

My guess is an injector, if anything else wouldnt all plugs be black?

No CEL light on.

Please help, all feedback very welcome!!

 
Rep Power: 246

Yes it could be an injector. You could have them cleaned and flow tested. You could try moving the injector to another cylinder and see if that plug turns black. Clean the plug first so you know for sure.

I've used this guy to clean and test my injectors:

http://cruzinperformance.com/fuelinj.html