Stuttering/Misfiring issue

[DSMTalonAWD51]

Does anyone have any suggestions for me? My car has all of a sudden started stuttering and misfiring at high rpms under WOT and doesnt accelerate well at all. My mods are in profile, 97gsx, big16g, stock injectors, walbbro 190 rewired , 15psi. So far I have tried:

new plugs, gapped at .028
took off my magnecors and put on stock wires
turned down boost to 11psi
my fuel filter is decently new

i did a 3rd gear log (dont have it on me)
and o2 stayed at .97
timing went from 6 to 13 degrees by redline

the log looked ok i dont think theres a fuel problem but i dont have a fuel controller anyway.

any suggestions? thanks

 

[andymoraitis]

I know you don't have fuel control and the 190 won't overrun the stock FPR, but what concerns me is the 13 degrees of timing up top. On my stock injectors and a 190, I was able to run 17 psi with zero knock. I'm not saying you should, but perhaps upping the boost will help.

If that doesn't work, I'd check for:

1. Boost leaks (will make you run pig rich)
2. Knock sensor (could be triggering false knock and pulling timing)
3. Plug Wires (I'd replace them with a brand new set if you're sure the Magnecor's are no good)

It's hard to tell without a log, so if you turn the boost up to 15 or 16psi and run one, we should be able to get a better idea. My inclination is to go with something simple like a boost leak and then work forward from there.

Get us that log!

Andy

 

[DSMTalonAWD51]

well i was running 15-16 psi no problems for a couple years now. Since this problem, i lowered the boost down to 11 just to see if that would help. I have an safc on the way so i can install some new injectors, but i wanted to take care of this problem and find out what it is before i go adding more parts. The timing doesnt really concern me right now i just dont kno why my car is driving the way it is. I still need to assemble a boost leak device and i am hoping thats the only problem. Ill try to get a complete log posted tomrow night. thanks

 

[andymoraitis]

Sounds great and we'll be back to have a look tomorrow. Usually on something like this, I go with fuel or spark, but I'll be interested in what comes up on your boost leak test.

Good luck!

Andy

 

[DSMTalonAWD51]

Well I got a log again tonight. I dont know how to upload them so i had to type it up, hopefully the image works. It looks like i am running rich tho so i am crossing my fingers that the stuttering is just a boost leak, i wont have time to make a tester until this weekend though.
heres the log: