problem with the KA-T please help

[Walaboom]

Hello everyone, I have this very weird problem from the KA-T i got from someone today. Car starts up fine, runs fine. I drove 4 hours back with that car without any problem and suddently when I was approaching a stop sign, the meter needle starts jumping between 500 to 2000 RPM and then the car just stall out. It doesn't happen very often, it only happen every once awhile. I have a super AFC, it wasn't tuned properly, it is reading the throttle, but not the air flow. Can this be the problem or maybe the MAF sensor or spark plug wiring? I have heard people with turbo on their KA are experiencing similar problem. Can you guys please tell me what might be wrong with the car?

Car is currently running stock KA with Xs engineering turbo and 6.5psi setting. I am not sure what other information I should be provided, please let me know if you need other info. Thanks.

Anybody happen to know any good shop at North Carolina that can tune the super AFC properly and maybe have the car check out w/o charging too much... I am a poor kid....

[Florida240sx]

It's not reading air flow?Isn't that how the SAFC work it gets the airflow signal than modifies signal to ECU correct?Is it the 1st version or second version of SAFC?

[Walaboom]

i think I have the first generation, when i drive, i can see throttle showing like 18%, 20% or so, but air is always showing 0.8% 1% 2% or 4%. it jumps everywhere, it is not reading the air. like when I hit the gas, the digital gauge (there are 3 modes) needle for throttle will move, but air will not.

[Import_Ant]

is your BOV recirculated or vented atmospherically? (is there a tube going from the BOV to the intake?)

I like to look for simple solutions and if you are vented atmospherically, if you abruptly let off the throttle at anywhere above 2000 rpm, your car will run rich and stall out like exactly like you described. if your bov is externally vented, try stiffening the spring and if you approach a stop like you have to 'blip' your throttle a couple of times to get it to even out. there is a dec.air setting on your AFC that can help fix this as well.

[Walaboom]

Import_Ant -

This is Xs engineering and it requires no BOV, therefore there is none.... The problem is really weird, it does not happen everyday. It only happen once awhile and it just happens.... Whenever it happens, either I let the car sit for awhile or disconnect the battery for a few min, then the car runs fine again for a few days.

I would think anything to do w/ the S AFC not tune properly and mess up the ECU and something to do w/ the MAF..??

I have also have my buddy drive behind me for awhile, car is not shooting any black smoke, it is not running rich.

[Florida240sx]

He's SAFC doesn't read air flow.Isn't that how it works?

[Import_Ant]

I'm really stumped then... I would suggest trying to contact Uncle_louie83 and asking about your SAFC. I know he's got one installed on his DOHC motor and seems to be pretty familiar with it.

[cyrus240sx]

even tho im not turboed i had almost the same problem on my 95 s14. it would stall out at stops and if i was at low rpms... turned out it was the maf sensor... so i bought a new one... fixed it