uh oh...

[r34 gtr]

i got the car running properly now (safc problem fixed). my dad said he was driving it the other day and he hit a boost cut. at 5000rpm it bucks like a friggin bronco and wont go anywhere until you let off completely and back off in the revs a little bit. the reason this is so damn puzzling is that ive got a friggin tuned ecu. i guess for now ill have to get a hks sld or something, anyone have any ideas? i guess i just got jipped. damn you swat tuning factory thingy!!

- tim

[Turbogixxer]

Check to see if he broke anything on the engine. Check the intake track behind the MAF and check for cracks and dumb stuff.

When a car breaks on a person that does not own the car, they sometimes lie to make it look like it is not their fault (no offence to your dad). Check the engine for damage.

[boost_boy]

i got the car running properly now (safc problem fixed). my dad said he was driving it the other day and he hit a boost cut. at 5000rpm it bucks like a friggin bronco and wont go anywhere until you let off completely and back off in the revs a little bit. the reason this is so damn puzzling is that ive got a friggin tuned ecu. i guess for now ill have to get a hks sld or something, anyone have any ideas? i guess i just got jipped. damn you swat tuning factory thingy!!

- tim

Run a diagnostic on the ecu to see what it codes you get. If you get 55, suspect the ecu is tuned for a little more than you have to offer which will warrant another ecu. "Turbogixxer" I don't think his dad will inadvertently damage his car and not share it with him. You haven't been around here long, so I'll tell you that they have been a team on this project and also, his father is a fellow speed-head that (IIRC) helped finance this as well.

Dee

[r34 gtr]

yeah, the car really is half his. he called me and told me that he had fixed the safc problem and that he got the car tuned properly, but that we were still hitting some sort of fuel cut at 5000 rpm. i just figure that its a boost cut seeing the size of the new turbo and stuff. the ecu says all is well and the car runs like a swiss watch except for the fact that it wont let you do high rpm's at full throttle in 3rd gear and up (probably 2nd if you really try).

dee, how would the cut mean that the ecu is tuned for more than i have to offer? (though i have always suspected it is). i would think retaining the boost cut would mean it is a very light tune.

- tim

[boost_boy]

yeah, the car really is half his. he called me and told me that he had fixed the safc problem and that he got the car tuned properly, but that we were still hitting some sort of fuel cut at 5000 rpm. i just figure that its a boost cut seeing the size of the new turbo and stuff. the ecu says all is well and the car runs like a swiss watch except for the fact that it wont let you do high rpm's at full throttle in 3rd gear and up (probably 2nd if you really try).

dee, how would the cut mean that the ecu is tuned for more than i have to offer? (though i have always suspected it is). i would think retaining the boost cut would mean it is a very light tune.

- tim

I figured maybe the ecu tuned for something a little bit more exotic like bigger injectors, etc, etc, but then it dawned on me that you have the super AFC thing. Answer me this one time, does it puff black smoke when it starts to buck and jerk? Maybe it's running out of fuel in that rpm range or your ignition is cutting out around that rpm range due to some kind of electromagnetic interference. Of course this is all speculation, Tim . Or just maybe you have some sugar in your tank .

Dee

[Def]

What's the S-AFC telling you the MAF % is when it hits the cut? You could try lowering the boost and seeing if that fixes it, and if it's always at the same MAF %, then you know what the problem is(at least I think that's how Nissan's stock boost cut works).

CAs are really easy to burn an EEPROM for(already socketed) - maybe you can get somebody on here to help you out and burn you a new chip and test that out.

[r34 gtr]

dee: well, this one time i went to start my go cart and found a whole peach in the gas tank, so i definately wouldnt put it past the sugar.

i cant give you specifics on what happens with the car as its not here. i did just realize that we have the boost controller running open so the actuator controlls the boost, but absolutely no idea what the stock actuator is set to. i also dont have the boost gauge hooked up yet. im thinking i need to do that ASAP so i can make sure it isnt set at like, 18psi and stuff. anyway, ill let you guys know whats up when i go home this weekend.

- tim