rb 20 2500 rpm fuel cut

[m1chaelhahn]

alright heres the deal. My car is running super rich, like 10.0-1 afr(i have an aem wideband 02 sensor, tons of black smoke. The car starts fine although the idle is a little high. around 1100-1200 rpms. when I rev the car to about 25-3k rpms the fuel cuts out kinda like im hitting the rev limiter. I know that when the engine is running to rich that the ecu will make adjustments like retarding the timing. I pulled off the maf cleaned it and that didnt help. I pulled the o2 sensor and it had a s***load of carbon build up but I am running hella rich. Im pulling a code 55 off my ecu which is basically saying everything is ok. Im leaning towards an injector problem or maybe a vacuum leak. Any body out there have a similar problem?

[moso240]

strange your pulling a 55 with a fuel cut...sounds like a MAF issue to me...

[pepegurr]

Mine did the same thing when my MAF was acting up, 2500 RPM cut and no code. Check your wiring.

[hisoka]

hey did anyone solve this, i just did a fresh swap. and getting same thing.

[Kevin.A]

I had a similar problem, what was happening was my maf was putting out too much voltage. at 2500 RPM the engine starts to make boost, the ECU cuts the fuel and spark to protect the engine if it thinks the car is getting too much air(running too lean)i would check to make sure your MAF is wired right, and that it's not passing threw too much voltage.

GL Kevin

[DeformityX]

I had a similar problem, what was happening was my maf was putting out too much voltage. at 2500 RPM the engine starts to make boost, the ECU cuts the fuel and spark to protect the engine if it thinks the car is getting too much air(running too lean)i would check to make sure your MAF is wired right, and that it's not passing threw too much voltage.

GL Kevin

I agree, definately sounds like a MAF to me... As he said, Check the MAF wiring, maybe take the cover off the box on the MAF and check the soldering... My RB25 was doing the same... I pulled the cover off and found two of the solder points cracked. Resoldered them, BAM! worked 100% again =)

[bloodspread]

im having a similar issue, my car Idles fine up until it it warms up then it just starts running rich and sounds like its misfiring, same thing happens if I accelerate, I cant rev past 3.8k then that point starts dropping as it gets warmer and starts running richer. Im going to take a look at my o2 sensor, im sure its not my MAF. any other ideas?

[Kevin.A]

Check your ignitor Mine had an i got one outta a wrecked car once, that someone had soldered threw the jelloey substance inside and when it got warm, it didn't work all the time. I recommend doing the Z32 ignitor swap(even if it's not the ignitor that's the problem)zerothread?id=116502

[hisoka]

hey guys just got back from swapping my maf with another one.

and guess what , car is still rev limiting at a low rpm. i checked the ecu and its throwing out a code 55 so thats all good

Modified by hisoka at 11:59 PM 1/14/2010

got a little blue wire coming out of the loom near the maf sensor ?

Modified by hisoka at 12:03 AM 1/15/2010

its a blue green wire with slive dots on it right near the maf
Modified by hisoka at 1:58 AM 1/15/2010

[JayySleazzy_s.trese]

Has anyone solved the solution to this problem, myrb20det is doing the same thing i also changed the maf and still did the same thing was thinking it might be coils but im not to sure anyone know any ideas..

[mixeds14]

Make sure your wiring is correct, some people tend to hook up the signal and 12v backwards.. Make sure u have the correct maf too. Btw a maxima maf is the same thing as a rb25 maf too(thats what im running atm) so u can source one at a local salvage yard.