Yet another fuel cut thread

[seanburns76]

So have read every fuel cut post i can find at least 3 times, yet i have still havnt found a fix.

First off whats happening, under boost in 1st gear revs up fine, 2nd cuts out at about 4500rpm sometimes, 3rd-5th cuts out somewhere from 4500-5500rpms.

I'm thiking its fuel cut but im not sure, everything i have read say its like "you're hitting a brick wall." its kind of like that, but im not 100% sure.

So mods list:
Walbro 255
660cc injectors
16g w/ 18psi
FMIC
apexi 38mm bov
gm maf
3" strait pipe turbo back
....i think thats about it

I have checked for boost leaks, found 1 in my piping. Thats been fixed still nothing.

I did a pull and had my buddy watch my boost gauge (so I could watch the road) and there was no boost creep at all.

Im planning on doing the fuel pump rewire once I get some cash (currently jobless) it should be soon. Also getting new plugs and wires soon.

Another thing that is possible is that I was thinking it might be running too ritch and fouling the plugs because under boost it smells rich. I do have a S-AFC but I don't want to mess with fuel levels until I get a wideband and can monitor.

I'm just trying to find something I might be missing. I understand if i take some flaming for another one of these posts but i really need help.

Thanks

Sean

 

[lovehatedsmRS]

You'd know if you were fuel cutting. You know how when your walking your dog and it starts to pull you, you jerk on it's leash and tell it to stop being an a*shole? Well thats what it feels like your car is doing. Except your the dog and the car is the leash. What exactly is going on that makes you think it's fuel cut?

 

[fenixnr]

You aren't tuning your car for the 660's and the extra boost is my guess so you car is hitting fuel cut. Get a wideband before you get ANYTHING.

 

[steve]

Wow.

You know we used to set these cars up all the time without a wideband and didn't blow anymore of them up than today.

You really shouldn't be driving the car around with 660cc injectors installed and no correction. A Walbro 255 pump and no AFPR or gauge to see if your overrunning the stock FPR isn't a very good idea either. If your SAFC is installed start out by taking about 40% of the fuel away across the board on the low throttle settings and then once the car is warmed up start making minor adjustments based on the fuel trims trying to get them to hover around 100%. You can do that in the driveway.

Once you dialed in the basic correction for the injectors using the feedback from the narrowband O2 across the closed loop RPM range, copy the last correction to redline and then copy all the RPM corrections from the low settings to the high settings. This is all just the basic settings to account for the larger injectors and not any tuning. The car should run pretty much like it did with the stock injectors except you have more fuel headroom now. Unless you still have boost leaks it should also put a dent in your fuel cut since you reduced the AirFlow the ECU sees by ~40%

 

[seanburns76]

Ok, I'l give that a shot. Not to sound totally retarted but im guess to check the o2 voltage i pull the plug and put a meter on it? Its supposed to read about 0.4x volts if what i have read is correct?