That's right. According to the FSM, the factory ECU only pulls timing if it detects a knock condition.themadscientist wrote:Just a hunch, but I would suspect the timing would get rolled back.
I drove the car today and wot it bogged and what happen to you happen to me.blownhemi wrote:That's right. According to the FSM, the factory ECU only pulls timing if it detects a knock condition.themadscientist wrote:Just a hunch, but I would suspect the timing would get rolled back.
Had a real similar problem last summer. Happened seemingly from one day to another, car would bog down 4200-4500-ish under high load. Both my boost gauge and AFR gauge was acting up, so I couldn't exactly tell if it was overboosting or not, or over/underfuelling. But it was definitely fuel cut, that kicked in.
We investigated some, and it turned out that the wastegage's diaphragm housing was leaking boost. Not much, but probably enough to cause overboosting. My builder fixed the leak with some teflon tape, that took care of the issue.
Did you look for boost leaks in that area, too?
Right now i don't know but my bf is going to test the wastegate pressure on the wastegate with a pressure gauge and see what psi its set on and i'll let you guys know. thanks guysfloat_6969 wrote:What boost pressure are you running on that turbo? It doesn't take much with the T28 to hit the factory boost cut. Maybe 12psi.
true what he said. we end up getting a chip ecu and now the car runs perfect! lol.s13drifter88 wrote:T28 and its cutting at 5500, sounds like the MAF is reaching peak resolution. Wastegate unhooked it prob made very little boost which didnt peak the MAF so it didnt cause the issue to present itself. Wire up a Z32 MAF and use your SAFC to translate it, I had this same prob with an SR T25 at 14psi. MAF swap and SAFC-1 later and it pulled all the way out to red at 14lbs