Bogging/Backfire @ High RPM

[Young Z]

So I'm having a bit of a dilemma with my L28et swap in my 280z. All is fine and dandy for the most part but I've been stumped by the problem that has been with me from the time that the car ran with the new engine.

 

The problem is that the car bogs/backfires at any rpm over 3k. If I try to force it through the "wall", it stalls and backfires very badly and then returns to normal.

 

So far I've replaced the fuel filter, checked all of the connections in the engine bay and sprayed it down for vacuum leaks on the intake manifold. My FPR reads a steady 35 psi at idle and it doesn't have this problem unless its under load. One other thing to mention is that my boost gauge that I have mounted rarely shows the turbo creating boost and the most that I've made was .4 bar. So hopefully you guys can help me solve this problem. I've read through the efi bible,searched for the past month on HBZ and looked through the online FSMs with no luck.

 

Oh and specs are L28et, stock ECCS, stock turbo, etc. Only modifications are a Auteq FPR and a MSA Downpipe.

[Challenger]

Do you have a stock fpr to swap out? Might try it just in case.

 

Also have you checked the ecu connections? Might get lucky and thats the problem.

 

Also your boost level seems about right. .4 bar is about 6 psi.

[Young Z]

Do you have a stock fpr to swap out? Might try it just in case.

 

Also have you checked the ecu connections? Might get lucky and thats the problem.

 

Also your boost level seems about right. .4 bar is about 6 psi.

 

Ya but the thing is with the boost gauge i'm always in vacuum even @ WOT. I've been meaning to borrow someone's boost gauge to see if mine is faulty but haven't had the chance to.