stumbling and choking after 5,000 rpm?
#1
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stumbling and choking after 5,000 rpm?
Hi would anyone know these symptoms and has the right remedy for it?
I've just installed an Vortech 12:1 FMU and 1.8 injector(clean and even flow).
Waiting to install Walbro 190hp FP, as soon as I could fix this problem.
I've just installed an Vortech 12:1 FMU and 1.8 injector(clean and even flow).
Waiting to install Walbro 190hp FP, as soon as I could fix this problem.
#6
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HMM... I wonder if the 12:1 is deadheading your oem fuel pump?
I ran up to 8psi with my 12:1 and walbro and 1.6 injectors. The pressure isn't the problem per se. It's how much flow you get at that pressure that makes your top end super rich. It's the o2 sensor or cat that can be harmed from being so rich. And maybe paint aroudn the tail pipe. There is no, or almost no, damage potential to the injectors.
I ran up to 8psi with my 12:1 and walbro and 1.6 injectors. The pressure isn't the problem per se. It's how much flow you get at that pressure that makes your top end super rich. It's the o2 sensor or cat that can be harmed from being so rich. And maybe paint aroudn the tail pipe. There is no, or almost no, damage potential to the injectors.
#8
Pull your timing back to 6 BTDC. You may be detonating. The OEM fuel pump will handle the 1.8's at up to 8psi if it isn't shot. Did you check your max fuel pressure? Make sure the Vortech is connected correctly and maybe open it to make sure you actually have the 12:1 disc in there(unless you got it new from GReddy)
#11
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OK.. .just spent 20 mins install the walbro... ! but the problem still the same, and now is comes in earlier before 5k rpm! AHHHHHHHHHHH!!
at half thottle, it was no problem up to 6k rpm... but WOT it chokes.
Could I be putting fuel in the system?
at half thottle, it was no problem up to 6k rpm... but WOT it chokes.
Could I be putting fuel in the system?
#14
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Sigh......! After another day at the shop looking though the system and decided to put in another FMU with dose 44psi at idle. (just for a try) The problem still not solved. Adding to that, as adviced by Olderguy, I put my timming back to 6 BTDC.
3-4 rpm holding at 3 psi boost, and doesn't want to creep up. once around 5k rpm starts to stumbles and choke again.
What i might do tomorrow is take out the AFPR, retain the OEM FPR... install the EMB, than put that on the DYNO.
3-4 rpm holding at 3 psi boost, and doesn't want to creep up. once around 5k rpm starts to stumbles and choke again.
What i might do tomorrow is take out the AFPR, retain the OEM FPR... install the EMB, than put that on the DYNO.
Last edited by Mimime; 01-11-2007 at 05:06 AM.
#17
hhmhmmmm....i dont have one either. but would this problem not have shown up way before?
I have been greddy turbo'd since 2004.
either the fueling is fucked.
My new o2 sensor has only been in 2 days and is going crazy on the AF guage.
somrtimes it just goes off na dcomes back on randomly and when i let of fthe gas.. really strange.
I have been greddy turbo'd since 2004.
either the fueling is fucked.
My new o2 sensor has only been in 2 days and is going crazy on the AF guage.
somrtimes it just goes off na dcomes back on randomly and when i let of fthe gas.. really strange.