hotimportcrx

my car has a b16 turbo with 12:1 fmu...walbro 255 fuel pump ...fuel rail pressure modifier...runnig like 9psi on my t3 on 240 cc injectors and it was runnig great but started getting fuel cutoff and bogging around 5k rpm....so today i installed some dsm 450 blue tops and its still doing the same thing cutting off around 4k ...but seems to be running rich...with smoke out the exhaust smelling like gas....i dont know whats wrong have any ideas...

s2kdre

wht fuel ecu do you have? u cant use bigger injectors with an fmu.

wantboost

iTrader: (2)

walbro pump + fmu + 450cc injectors = too much fuel.

sell the fmu and run real fuel management

hotimportcrx

right now the car has a pw0 ecu but i will be converting to odb1 and tuning it by june 31st.....i just dont know whta the problem is now...it was even cutting off with the 240's...but the first 3 weeks with the 240's it was running perfect....all of a sudden it started messing up...they were stock crx injectors...and the timing is at 13

Chip

Your motor still thinks it has stock size injectors so it's pouring in fuel

wantboost

iTrader: (2)

at 9 psi, the fmu bumps fuel pressure up to 108psi plus whatever you are running at the rail.... you were running way too rich with the stock injectors, thats why it would "cut off" or die. now you almost double the injector size.. of course its not gonna run, lol

hotimportcrx

yea but it was running perfect before......do you think i put to much of a load on the stock injectors and messed them up??......or maybe its cutting off because the spark plugs could be bad...the cars not shutting off its just ....you can feel the fuel cutoff ...where it doesnt get any fuel

chirp3rd

i had the same problem with my fmu setup when i threw in 370cc injectors car would bog as soon as it hit boost then it would backfire hard *** hell then pull even dumping fuel wit my vafc wouldnt fix this problem people told me that it was the ratio of the pill in the fmu 12:1 pill that you are using would dump way to much fuel with bigger injectors you can try using a lower ratio pill i never tried it because i was only able to run 12 psi before the 370cc were maxxed so i threw in my stock injectors they were good for 10 psi and now saving 4 a standalone system. I hope you have a wideband and a vafc cause FMU's setups are very tricky.

300whpOrBust

silly question but whats an fmu?

crew08 (girlygirlracer)

Fuel Management Unit (F.M.U.)