rb25det not running like it should! HELP PLEASE!!

[skylinebeginner]

So my r33 gtst (rb25det) I got it just before winter so I only had a couple weeks to drive it in temps from -1 to +9ish and when I'm in first gear and I go wot it picks up rpm really quick and just hits the rev limitter but in second it will pick up to 3700ish rpm and start to sputter and not get up and go like it should till it sputters its way up to about 6000 ish rpm then it clears out.. the only gear it actually runs good and right in is first, any ideas what the problem could be ? I wanna get it running good before summer! It has the following mods: 3 inch straight pipe to fart can, fmic, mines tuned ecu, bov,turbo timer and that's about all... please and help or advice would be greatly appreciated!

[skylinebeginner]

Its a s1 if that matters

[h4X6]

Sounds like its in limo mode.

Check for codes on ecu

Sent from my Nexus 4 using Tapatalk HD

[SlidingSideways]

Check out the thread called "fix your hesitation" and go through the list.
Mine was doing the same thing, just between 4000-5500 rpm right when I got it
I did some stuff from that thread and it turned out to be my MAF

-got a Maf from a 96 maxima at the wreckers for 50$ and it fixed it

Not saying that's what it is in your case, but that thread will help you diagnose the problem

[bourquetc]

check ya plugs mine spluttered and thats wat it was could be the simplest thing

[Skym]

Missing at higher rpm = sparkplug gap and result of that is failed coilpacks (usually 2x coilpacks and the other coilpacks are ok).

If missing at around 3000-4000rpm, can be coilpack related or have intake airleak just before MAF if MAF has a clamp on type of airfilter setup (MAF makes ECU hit boost cut limiter, which is a fuel cut). Sometimes the airleak is just after MAF (loose intake hose clamp on MAF or intake hose clamp put a hole in rubber intake pipe, have crack inbetween ribs on rubber intake pipe after MAF). This airleak behind MAF causes stuttering, which can be easily mistaken for missing coilpacks (similar missing).

When MAF goes, get MAF error code on ECU, engines idles at 1500rpm when cold, hot. Sometimes MAF hotwire gets oil on it from wet type airfilter and can't burn it off, so attracts dirt and causes problems. Sometimes it's the solder on plug side inside square part of MAF (pop lid, resolder on plug side and look for bad solders). Bad solders is common on Skylines, inside engine ECU, HICAS ECU, behind dash, inside square part of MAF, etc. In some cases it can be wiring related, falling out of plug on ECU side or on MAF side or ECU plug not seated correctly in ECU and is bent when bolted down. Lightly tapping on wiring, MAF itself should reveal that wiring into plug problem.

[skylinebeginner]

what kind of plugs do these cars run and what gap?

[nick-nismo]

bcpr6es , gap them down aswell. 0.24 - 0.28