95 gsx, power stops at 4k. runs like a n/a motor.

[blktalon95]

This is a dramatic car!
i'm not new to cars, so its nothing like a slipping clutch, the engine is rebuilt and has exelent compression all round.
but as the turbo spools, the car pulls hard till it reaches [email protected] {my max boost} but then it just hangs there and slowly revs higher, as minivans pass my slow ass.
I have replaced fuel filter and pulgs NGK BPR6ES .28, and wires and have a new CAS sensor.
I have boost leak tested, and i'm sure i have some little leaks but it holds 20psi for about 20-30 seconds. shouldn't that be O.K?
i feel like i shouldnt have to buy any more parts at this point, so any help is welcome....


My only other ideas would be a clogged cat? bad MAF or ECU? Car just wants more of my money?

 

[mhuffman]

This is a dramatic car!
i'm not new to cars, so its nothing like a slipping clutch, the engine is rebuilt and has exelent compression all round.
but as the turbo spools, the car pulls hard till it reaches [email protected] {my max boost} but then it just hangs there and slowly revs higher, as minivans pass my slow ass.
I have replaced fuel filter and pulgs NGK BPR6ES .28, and wires and have a new CAS sensor.
I have boost leak tested, and i'm sure i have some little leaks but it holds 20psi for about 20-30 seconds. shouldn't that be O.K?
i feel like i shouldnt have to buy any more parts at this point, so any help is welcome....


My only other ideas would be a clogged cat? bad MAF or ECU? Car just wants more of my money?

My problem is similar. below 4k rpm's, it pulls and boosts strongly. above 4500rpms, it stutters and i have NO MORE acceleration like a rev limiter.

 

[booostedGSX]

I sounds like for some reason the ECU is drastically retarding timing. If you can, find an ECU that is good and try it out. If it helps, you've solved your problem. If not, you have eliminated a possibility. If I think of anything else I'll post up.

 

[mhuffman]

I sounds like for some reason the ECU is drastically retarding timing. If you can, find an ECU that is good and try it out. If it helps, you've solved your problem. If not, you have eliminated a possibility. If I think of anything else I'll post up.

i have been thinking ECU as well. timing wasnt pulled (verified with datalogger) but that doesnt mean the ECU was sending spark.

 

[blktalon95]

Well it's fixed?
I have no idea why, but the day after i posted this query, the eclipse pulled hard all the way to red line!
It runs great after six months of gutless performance, and i didnt even pop the hood!
Is it just me or are Mitsubishi's spooky? perhaps you really do need a data logger to fix anything on these things?

I guess that the ecu woke up and started working, or perhaps i had a clog in my cat and it burst?
Who knows?
But i can do 4wd burnouts now, and i am loving the boost! i only got 200 miles on my last tank!

 

[96mitsugsx]

Check your cat. That's one of the symptoms of a clogged cat.