Is it fuel cut?

I installed a FMIC for my WRX, and I noticed that it jumped from stock 13 lbs of boost to 15 lbs of boost. And when i run it at higher rpm usually during 5th gear the car will suddenly stall and i feel a hard jerk as if the engine had stop for a bit until i let off throttle and also experience a sudden loss of power. So i was just wandering if this is fuel cut due to the 2 lbs boost increase and what can i do to make it stop. Any help would be much appreciated thanks!

~Lee

 

Could be the wastegate opening bacuase it's seeing too much boost for the map you have. Is it the stock map your running?

 

is it spiking?

 

did you upgrade the turbo... if not maybe its hitting the limit of the turbo and running out of breath....???? most poeple say adding a FMIC without all the additional upgrades is a waste unless its for looks...?!?!?!?!

 

any turbo will spin itself to death...it will be pushing as many psi as it wants..but it will be molten hot air...so i doubt its that

 

In the Mitsubishi world, these symptoms would be fuel cut. The way you'd get it is to use the factory BCS and remove the restrictor. That would increase the boost about 3 psi. On a nice cold day at WOT, you could sometimes get fuel cut. It was like hitting a brick wall. Increasing the fuel by either a fuel computer or FPR usually got rid of it. Base fuel pressure was around 40 psi (roughly, give or take) when you hit boost the fuel pressure was increased 1:1. Since the computer still thinks it's getting X amount of boost and you are feeding it Y amount of boost, you lack fuel. It's leaner now. It's also leaner because it's cold, air is denser and you lean out a little due to that fact alone. Answer? More fuel. A logger or wideband would probably help diagnose better than people on the internet. Check for injector duty, see if it's maxing out. Another idea, check for boost leaks.

 

Really you don't think it's fuel cut? the very same thing happend to me once, when my boost controller got disconnected. Same symptoms and I got a cel. From the stock map I pulled it appears 17.4 is the fuel cut on a stock 04 map.

I'm not trying to argue with you Russ, just trying to understand this better am I reading this wrong?

 

thanks alot for all your help and yes im still running my stock td04 turbo my current mod is the TBE and a short ram intake because i cant use my stock one anymore oh and yes i am using the stock map and no my boost is not spiking its consistant.

 

I know we had a wrx with similar symptoms come in before. I think the factory EGT sensor was going bad and when it seems it's getting too hot, it cuts boost. So it's kinda like Boost Cut.

Are you running any type of managment...Cobb AP, U-Tec, ECU-Tek.... Your factory EGT may be on it's last leg also... It won't set a code until it has failed...for this situation anyhow.

 

I'm a Noob, and just read that you are still running factory map. You may have an EGT code already stored. Is your CEL on already from a P0420 from being cat-less? If the EGT sensor has broken, I bet that's what is happening. You hitting boost cut because the ECM thinks your engine is on fire. I've felt it happen before, and it could very well be what your feeling.

 

Ok.... wait.
your running a FMIC... on a stock 04 WRX? Do you have ANY engine management? Exhaust modifications?

You better just post a mod list here man... the more info you give, the easier it would be to diagnose your problem.