Well here is the deal I have a Megan Racing Manifold, Downpipe, Test Pipe, Stock Cat Back and a Vishnu XEDE. Well in 3rd or 4th gear whenever and only when I get on the throttle 100% in the 4000 and up range it'll randomly stutter. It feels like I hit a wall and then it pulls again and it stutters again sometimes and eventually the CEL gets thrown.

 

sounds like it may be to rich.............. needs a better tune

 

fuel cut? boost cut? how much boost are you running?

 

that too.

 

whatever the 330 + map is pushing, My boost guage shows it building to 21 and in some cases 23 in 5th gear. Also my bumper by my exhaust is black so maybe even with the Vishnu maps I am running too rich?

 

spark plugs gapped too wide?

 

your plugs maybe going bad, I had that happen to me.

 

where is your timing? can you log ?
does the vishnu have a boost map?

 

yes there is a boost map, and i believe you can log timing along with other stuff

 

I would say that either you are running to rich, map need modified..

Or your plugs are either bad, or gapped wrong. With your mods you would be fine with br7es gapped to .023

 

guys you have to be SO rich to get over fueled. I mean I doubt you can feel it unless you are 10 or lower.
timing on the other hand you can feel. could be bad gas, maybe plugs.

 

Same thing happened to me. It was the spark plugs. Now I put in NGK PBR7ES at every oil change (5000 miles).

 

First off this should be in the Vishnu forums,

Did you by any chance take your car to the dealer and have it serviced? They might have reflashed it with their own software because of some code and that may have messed it up. I had the exact symptoms right after my car got reflashed for a code by my dealer, but I never put two and two together. I just thought that it was something that happened once in a while. Then finally when I took my car to Vishnu to get Stage 2'd, they told me the car was running funny and one of the first things they asked me was if the dealer had reflashed it.

 

have stock plugs gapped to .023

 

fuel cut, wires, plugs, one of those things