# Car running lean



## Jarzone (Aug 13, 2015)

I have a 2006 GTO with intake, headers, exhaust and tuned. I got the car tuned back in September and just yesterday my check engine light came on saying bank 1 and bank 2 are running lean. Need help on what it could be. Thanks


----------



## svede1212 (Nov 1, 2005)

Fuel pressure should be one thing to check. The MAF and connections would also be a good thing to check. Any vacuum leak past the MAF can cause a lean condition. What "intake" do you have?


----------



## Lemans guy (Oct 14, 2014)

Spot on advice, I would just build on that advice and say that both banks reading lean eliminates an individual fuel injector problem for example and points to any system that effects the total fuel air delivery......

It can mean too much air.......or not enough fuel.....

Too much air, vac leak as described or some other say,...stuck open dirty Idle air control....

Or too little fuel....such as clogged fuel filter, weak fuel pump, bad fuel pressure regulator.....

These modern cars are very sensitive to fuel pressure, just a few psi off and it will effect the systems, check that fuel pressure first!


----------

