You could have boost levels causing fuel cut that wasnt an issue in the summer, Your getting more air at the same boost level because its so fucking cold.
11psi of boost and hitting fuel cut off.
- Thread starter jamesmwalker79
- Start date
I have what sounds like the exact same problem, filter 3" Turbo back (stock cat) and I hit 8+ on the factory gauge it sputters, backfires CELs and kills the throttle for a second. LMK what you come up w/ please.
Ok, after reading though this thread hearing everyone talking about injectors.... as Viper said, injectors have nothing to due with fuel cut!
Fuel cut is caused by your AFM, it reads in Hz.... fuel cut normally happens ~1400hz. The colder the air gets the density increases, this causes more air to enter the AFM, the more air that enters the AFM the sooner you are going to hit fuel cut.
So to the OP, Since your in Oregon I'm assuming its not exactly warm there hence why your hitting fuel cut sooner.
If your hitting fuel cut in warmer weather at 8psi, you most likey have a boost leak somewhere.
If your not sure if your hitting fuel cut, pull your codes, code 34- turbocharger pressure is fuel cut.
Fuel cut is caused by your AFM, it reads in Hz.... fuel cut normally happens ~1400hz. The colder the air gets the density increases, this causes more air to enter the AFM, the more air that enters the AFM the sooner you are going to hit fuel cut.
So to the OP, Since your in Oregon I'm assuming its not exactly warm there hence why your hitting fuel cut sooner.
If your hitting fuel cut in warmer weather at 8psi, you most likey have a boost leak somewhere.
If your not sure if your hitting fuel cut, pull your codes, code 34- turbocharger pressure is fuel cut.
RogueSteel;1505618 said:
Did you actually check? Just cause you don't have a check engine light flashing doesn't mean you don't have codes...
Dear op
adding a lexas afm will increase fuel threshold but you need to make sure that your car can handle the extra power...has your engine be rebuilt? Are you running the stock headgasket?
Don't just go turning up the boost and doing mods unless your shit can handle it.
Rogue: Did you check properly?
Yourenemy: In my experience its about 1550HZ @~80F. Maybe 1400hz is winter? And it being colder doesn't change the HZ. The frequency is based on airspeed. The mass air flow is calculated by the TCCS Using the airspeed frequency and a temperature reading.
The TCCS will cut fuel based on this mass airflow reading, in other words a combination of the two. If its very cold fuel cut will happen at a lower frequency because at the same air speed, more air mass is moving.
Same principal of climate change effecting fuel cut though. Not arguing with you just clarifying what you said.
James: If you put on a lexus AFM you will most likely need a SAFC to tune the now lean condition you'll have with stock injectors.
I would recommend a SAFC either way as it will make a HUGE difference if you get a wideband and lean out the mixture a tad. IT will also raise fuel cut if you lean the mixture from the stock 10:1 pig rich tune.
Everyone: If you have boost levels in the 9+ Area on stock electronics (READ: AFM and TCCS WITHOUT tuning of any sort) and the car is cutting out, YOUR HITTING FUEL CUT. Nothing is going to "FIX" this.
Mistakes are costly and leaning from your own mistakes is time consuming.
Yourenemy: In my experience its about 1550HZ @~80F. Maybe 1400hz is winter? And it being colder doesn't change the HZ. The frequency is based on airspeed. The mass air flow is calculated by the TCCS Using the airspeed frequency and a temperature reading.
The TCCS will cut fuel based on this mass airflow reading, in other words a combination of the two. If its very cold fuel cut will happen at a lower frequency because at the same air speed, more air mass is moving.
Same principal of climate change effecting fuel cut though. Not arguing with you just clarifying what you said.
James: If you put on a lexus AFM you will most likely need a SAFC to tune the now lean condition you'll have with stock injectors.
I would recommend a SAFC either way as it will make a HUGE difference if you get a wideband and lean out the mixture a tad. IT will also raise fuel cut if you lean the mixture from the stock 10:1 pig rich tune.
Everyone: If you have boost levels in the 9+ Area on stock electronics (READ: AFM and TCCS WITHOUT tuning of any sort) and the car is cutting out, YOUR HITTING FUEL CUT. Nothing is going to "FIX" this.
Mistakes are costly and leaning from your own mistakes is time consuming.
I went to put in an MBC and I found to things.
1. Turbo is pretty much toast so thats why I'm smoking.2
2. The Turbo nipple was running to the PS vac instead of the wastegate, and the wastegate was running to the intake.
So I re routed the turbo back to the waste gate and the PS idle to the intake and now i'm GTG
1. Turbo is pretty much toast so thats why I'm smoking.2
2. The Turbo nipple was running to the PS vac instead of the wastegate, and the wastegate was running to the intake.
So I re routed the turbo back to the waste gate and the PS idle to the intake and now i'm GTG
SupraSean;1506833 said:
I'm going to have to go with this also...
I had a very very similar problem running stock boost it would feel
exactly like fuel cut, check your lines around the turbo, listen for whistles
etc etc.
Theres one hose specificly that is right next to where your IC piping hooks onto your turbo, check that one.
Cold air = more dense
Hot air = less dense
10-12 psi is about normal for fuel cut on stock system. Every car is different. No exact number for fuel cut.
:3d_frown:
Hot air = less dense
10-12 psi is about normal for fuel cut on stock system. Every car is different. No exact number for fuel cut.
:3d_frown:
ok i checked all piping and hose's no leaaks. so what year and model lexus afm do i need? cause theres 3 in the junk yard here so i might get lucky.
Mostly anything in the 90's with the 4.0 liter V8. I know the ls400 is a good candidate off hand.
You do realize just putting on the Lex AFM will not fix the problem right? Any will likely result in you starting another thread asking how you blew the motor up?
Why not make the car run properly stock and go from there the right way the first time?
You do realize just putting on the Lex AFM will not fix the problem right? Any will likely result in you starting another thread asking how you blew the motor up?
Why not make the car run properly stock and go from there the right way the first time?
nosechunks;1507290 said:
i got the arp head bolts in route same with mhg. so i shouldnt blow anything up after those are installed.
