Nice day for a Photo Shoot! (56k This will never load for you)

[Galant306m]

How about this for Ground Clearance??

[SkylineG1]

Looks good guys. Voodoo exactly when do the sputtering starts? Under acceleration?

[Galant306m]

It starts when he gets into boost, at about 7 psi the map sensor starts freeking out.

[SkylineG1]

It starts when he gets into boost, at about 7 psi the map sensor starts freeking out.

is it tuned?

[fliegendaffe]

is it tuned?

if i remember correctly, he did get it tuned a few months back

[Galant306m]

is it tuned?

yea he has been going though tunes like no other and everyone keeps giving him the same problem.

He fixed some boost leaks and a fuel pump problem and he still has the same issue.

If i could get ahold of him i could get him to post some of the readings from his AEM that show his boost curve which goes all over the place and the map freaking out.

[4g63lover]

It starts when he gets into boost, at about 7 psi the map sensor starts freeking out.

did you guys try to change the MAF?

check the injectors

theres gotta be more boost leaks.

actually, check for an exhaust leak too.

at about 7psi it shouldn't be fuel cutting unless he's on 200cc whatever injectors...

so idk. but try the injectors anyway.

ignition is another thing he should check out. check the coilpacks. make sure he's not fouling plugs out either.

idk what else to throw out but I wont know until I can get in the car.

let me know if you guys figure it out

[Voodoo]

Well, here's the deal. I'm running an AEM EMS. I no longer have a MAF as I'm using speed density. I'm running 450cc DSM injectors. I haven't felt the need to check them because I've pulled my plugs many times and all the cylinders are burning evenly.

The car starts sputtering usually around 4500 RPMs. It sputters worse at higher boost levels, higher gears, and seemingly also when it's colder outside. These are the parts I've replaced while troubleshooting:

Evo VIII fuel rail + FPR
Walbro 255lph FP
Injectors (swapped with a different set of DSM 450's)
Spark plugs (iridium and copper plugs at various gaps between .020"-.040")
Coil packs + wires (replaced with stock coils from another motor, never aftermarket ignition)
Fixed 2 big boost leaks

I recently ran new power and ground wires to my Kavlico 3.5bar MAP sensor because it wasn't reading correctly and made my car nearly undriveable. I had my MAP sensor wired into the stock MDP wires, and they were only producing 4.92V. I have a Zeitronix Zt-2 wideband that comes with a +5V power supply for wiring a MAP sensor, and it was supplying 5.01V. The MAP was reading much more accurately and consistently afterwards, so I'm suspicious I may have some wiring/grounding problems somewhere.

The car runs a pretty consistent 11.3-11.5 AFR under WOT at 7psi, and I haven't been able to see anything on the logs, but I will try to find some useful ones and post them up. I am running a base calibration from Scot Gray at Road Race Engineering that I have tweaked slightly (mostly just the fuel table and idle).

I brought it to a dyno last summer to have it tuned, but he couldn't get rid of the sputtering and said it sounded like ignition breakup. He couldn't tune it because of the sputtering, so I don't think its tune-related. He tried retarding and advancing timing, and running it leaner/richer, nothing seemed to work. He also replaced the spark plugs.

For a long time I thought it was ignition breakup too, but it has gotten worse over the past year, and I've replaced spark plugs several times.

Any ideas now?