R33 "surging"

[Rolls]

Check the timing and TPS volts with ECUtalk when the revs are jumping with static throttle.

If either of them are changing it sounds like a buggered TPS or possibly CAS or knock sensor, any of these as the potential to change the timing causing weird issues like this.

ECU talk should be able to diagnose this problem for you. Another thing to do is enable datalogging and do some 0-redline launches and compare the datalogs of when it 'surges' and when it doesn't, should show which sensor is causing the issue, if none then look at fueling and ignition sources.

[nsdq]

mate curious to know if you have discovered the cause?

my 33's behaving similarly lately.

cheers

[Rolls]

everyone wants a fix but no one is willing to datalog, it is simple and should show the problem.

[Mr. Pav]

+1 TO ROLLS

[Dasmbo]

mate curious to know if you have discovered the cause?

my 33's behaving similarly lately.

cheers

Hi i had a similar problem with my r33 and did the new spark plugs then new coils with very little improvementi then i checked the timing and it was at 20deg so i changed it to 15deg and cleaned the ACC valve as it was really gunked up and now it is going like a bullet again and the fuel comsuption is back to normal.

hope this is some help to you

[Rolls]

Maybe the extra timing was making the knock map cut in? Or maybe it was just hitting richer and more retarded maps due to it for some reason, certainly sounds odd,you would think extra timing would make it perform better and get better fuel economy.

[Logikal]

mate curious to know if you have discovered the cause?

my 33's behaving similarly lately.

cheers

Almost 100% sure it was the coilpacks alone - After I got new splitfires put in, she purred like a kitten. Nice and smooth to drive.

Surged a little bit after the new coilpacks were put in but I replaced the AFM just for the hell of it and seems like the issues are gone.

Thanks to everyone who gave constructive ideas/feedback.

[Rolls]

Sounds like the typical too much boost with stock tune blowing out spark with old aged coil packs. Two issues, one the spark is weak due to old coilpacks and two the engine is running very rich (rich retarded upper quadrant of stock map often called R&R) making blowing out a spark even easier.

New coilpacks will often fix the problem, or only make it slightly better, a full remap with a nistune or aftermarket ECU will fix the problem completely, add more power and increase fuel economy.

Other faulty sensors such as AFM, O2 sensor etc that can make the car run even richer can also make the problem worse.

Sounds like you have a little from all areas, good to hear you fixed it!

Edited November 28, 2010 by Rolls

[Logikal]

New coilpacks will often fix the problem, or only make it slightly better, a full remap with a nistune or aftermarket ECU will fix the problem completely, add more power and increase fuel economy.

How much do nistune remaps go for these days? I was under the impression that only manual ECUs can get it done?

[ZED X]

How much do nistune remaps go for these days? I was under the impression that only manual ECUs can get it done?

Fairly certain you can use an Auto ECU with Nistune.

Depends what workshop you run through, however im looking to remap/tune my 32 GTR within the next month or two, was quoted $700 installation and tune. Assuming no other issues are found during the process of course