i know this may sound like a noob question, but i've never experienced it. what are the symptoms/sound of fuel cut? also if i have my utec running passive(map 0) with the FCD switch off, will this have any conciquence?

 

Fuel cut is when you rev past redline and the ecu says "whoa too much!" and stops fuel so you dont cause damage to the motor. Just dont misshift from like 5th to 2nd, fuel cut wont help there

 

reason that i'm asking is i just installed a ported vf34, helix 660cc inj, and 255lph fuel pump with all supporting mods. and now the most boost that i can get is .04 bar. i have a utec as EM and also the TXS tuner lite. i'm running everything right now on the stock ecu cause i havn't had time to play with the TSX stage 4 map. when i get on the gas, it spools till about .04 bar then i just goes flat. help!!

 

what do you mean by "'i'm running everything right now on the stock ecu cause i havn't had time to play with the TSX stage 4 map"?

you cant run in stock mode w/bigger injectors.

 

Your probably in limp mode. Get that tune done quick.

 

Fuel cut occurs when you hit boost levels that ECU was not tuned for. It is a ECU safety measure to prevent overboost. When it occurs, you will feel like someone stepped on the brakes and the car will drop RPMs momentaraly.

What Subie OCD described is basic Redline, not fuel cut. Redline is actually done by cutting the spark, not fuel.

If you have all the mods you have described above but still running on stock map, your car is running very poorly. Basically get it tuned ASAP.