2 bar 2010 Camaro - STS Twin kit - Very lean at startup

[Alvin]

Hey Guys,

I just did a 2 bar 2010 camaro that turned out fantastic. Car drives like stock but with almost another 200 rwhp. Fuel trims are all really close +/- 3% but when you first fire the car either hot or cold shes very very lean. On the order of 20-30% leaner than where I'm commanding in OL

Has anyone else had an issue with this?

I will say that on cold starts the turbos sit still, they do not spin until the car gets some heat into it. That doesn't sound normal to me but seeing how you can't normally see the turbo's exhaust wheel I don't know if it is or not. I almost feel like the turbos sitting there stopped is choking the car up. Once they start to move the car runs perfect again. If you rev it up a bit and get them going the car seems to straighten out.

[carlrx7]

if the turbos are blocking the air, why is it lean?

[DSteck]

I couldn't tell you, but until mine is in closed loop (ie: during warmup or during startup enrichment), the commanded AFR and actual AFR don't match. I just shrugged it off.

[Higgs Boson]

Mine don't match either for several seconds.

[EC_Tune]

EVAP plays a big role at/after startup. Log it and see.

[Alvin]

Hey guys,

Update..

We deleted the resonator (DOD) and no more problems. The turbos also spin now from a cold start where they where stopped before.

If you do a STS automatic 2010 camaro make sure you delete the resonator.

[99LS1SS]

EVAP plays a big role at/after startup. Log it and see.

What type of role? What should we be looking for?