Boost Issue

[180mph]

I don't think that running "lower boost" will mess with your afr.

My argument here comes with how I'm self tuning my new corksport turbo. For safety I set my wgdc to 0 across the board on first startup. This forces my boost to 14-17 psi off wg spring pressure.

Even though I'm "targeting" 20 psi and actually achieving 14 psi my AFRs stay around 11.2. The ECU is much better at correction than you would think.

If nothing mechanical has changed from log 93 to 94/95 I would really be suspecting an air leak with intake/vac etc.

Sorry I can't be of more help

PS... Confirming proper operation of the BCS also seems like a good theory to the problem... I have nevy experienced a failing one so this could be useful knowledge for me in the future

[Sensei]

Originally Posted by 180mph I don't think that running "lower boost" will mess with your afr.

I was refering to Pu Manchu's suggestion that a boost leak was the cause of the problem. If the car was losing that much air after the turbo I think we'd see it in the logs. AFR would be rich since the car expects more air to be going to he engine. MAF voltage/flow + boost wouldn't match between logs 93 and 94/95 which they do match. IIRC boost is measured at the intake manifold so low boost with a realatively higher MAF value and rich AFR is what I'd expect out of a substantial boost leak.