Lean idle when warm, checked basics - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

di-devol · 04-16-2012, 11:14 AM

Walbro 255, removing the gascap, there usually is a pshhh sound yes, Fuel pump sounds normal, Manifold to turbo, s15 gasket, studs, nuts tack wleded, with locking tabs ahaha(I had problems previously with that).

I did have an exhaust leak where the DP meets the Cat when I was on the dyno.
When we upped the fuel pressure to 85psi, when building boost it showed rich about 10afr, then as started to climb to about 15afr at 5500rpms. I know an exhaust leak would show lean, but I wouldn't think it would get worse exponentially(ish) like that(especially starting off rich).

04-16-2012, 11:14 AM	#11
di-devol Zilvia FREAK! Join Date: Jun 2010 Location: Woodinville Age: 43 Posts: 1,412 Trader Rating: (5) Feedback Score: 5 reviews	Walbro 255, removing the gascap, there usually is a pshhh sound yes, Fuel pump sounds normal, Manifold to turbo, s15 gasket, studs, nuts tack wleded, with locking tabs ahaha(I had problems previously with that). I did have an exhaust leak where the DP meets the Cat when I was on the dyno. When we upped the fuel pressure to 85psi, when building boost it showed rich about 10afr, then as started to climb to about 15afr at 5500rpms. I know an exhaust leak would show lean, but I wouldn't think it would get worse exponentially(ish) like that(especially starting off rich).