S13 SR20DET into S14 Kouki.. will not rev past 4k rpm

[Rican_Nick]

i have been trying to help a buddy resolve a strange issue on his SR swap that was completed last weekend.

Car info..97 Kouki with s13 blacktop sr20det Stock e6 ecu. The swap itself is very stock.. SMIC, Stock BOV, stock downpipe. Only known mod on the motor is a M's K&N intake. HKS Wastegate actuator.. from waht we can tell it is set to stock boost.. but not sure if we are building full boost due to the rev limitation.

quick rundown on where we are at.

Problem- Will NOT rev past 4k, at WOT the motor sits on 4k as if there was a ECU controlled Ignition/fuel limiter. Also having cold start issues.. takes 4-5 times to crank over. the motor will idle fine.. but the slightest load or revving causes it to "break up" occassionally.. some times it will rev up to 4k even building boost appropriately and then hit 4k and not rev past it at all.

things we have done checked.

Motor Grounds- Goodnew plugs- Gapped at .34 ish.. Will gap these down to about .30 which is what i ran on on my plugs stock boost.Tried my Working maf - nothingVerified the Timing and it is on pointNo boost leaks that we have foundall connectors have been checked/cleanedWe have checked voltage at TPS/Maf/coil packs.. all check out finewe have checked the 5th gear sensor to verify it hasnt gone haywire--this usually causes problems at 5k rpms though.. but we are running out of Ideas.

does anyone know of an ECU imposed limiter that would limit the motor to 4000rpm.

I have found many other threads with the same exact symptoms but none that state they were able to fix the issue and/or how they resolved the issue.

Any help would be greatly appreciated..

[scott240sx]

you forgot the hks wastgate actuator

[jetdriver]

Are the fuel lines on correct , inlet and return? What is fuel pressure?

[teddy]

Stock boost as in..8psi stock boost...or HKS actuator 12psi stock boost? Still running on the stock fuel pump as well?

[Rican_Nick]

Fuel lines are on correct

We have not checked actual fuel pressure and i am suspect to it also as he is running stock fuel pump

Stock boost as in .5 bar 7-8psi.. at 4k rpms its only building about .5 bar... it may be set higher but at this point we can not verify as it wont rev past the 4k mark.

as i stated i suspect hte fuel pump but dont really understand as to why it is almost a "limiter" not really a fuel starvation feel.. i mean it literally feels like the car has a launch control module limiting the car at 4k even with the peddle held all the way down.

I am going to try to find a fuel pressure gauge to check the fuel pressure just to cover it.

thanks for the help guys

[scott240sx]

i tried a different ecu today and nothing changed but i did get a code. i got code 55. i wish a different code came up to help me out. tomorrow i will try to replace my fuel pump with the s13 sr fuel pump.

[scott240sx]

i forgot to say that while driving home today the boost went up to .9 bar and it freaked me out because i know my car cannot handle that yet.

[scott240sx]

i just replaced the fuel pump and there were no changes in how it runs