Hi,

Ok have put the 1600cc secondary injectors, Walbro 255 lph and a secondary Fuel Rail...

Drove the car but still the same problem... massive hesitation above 4000 rpms and at 8 psi of boost... i floored the car 2-3 times but it was the same everytime...

So i brought it back and opened the plugs and found that they were redish... showing that the car is running very lean... No fuel.. the plugs should have been blackish... but it seemed there is severe lack of fuel... What should i check..

I am thinking of slapping on a AIC and put additional fuel in the car... but i want to know whats wrong... why is it not getting proper fuel above 7-8psi and 4000 rpms?

Seems like the secondaries are not working at all... HEEEELLP... are there any solonoids or electronic controls.. becuase if i keep the boost at around 7 psi max the car runs fine...

Here are my mods

Non-Sequential turbos
Apex-i Intakes
Apex-i GT Spec Radiator
Apex-i Power Fc
1600cc secondary injectors
Secondary fuel rail
Walbro 255 lph

Please tell me what cud be wrong... Need help bad... Please give me some direction...

Thanks...

 

Um, you seem to have answered your own problem.

Obviously your fuel system isnt working properly.

Either that or you need to get your pfc retuned.

 

With those mods and 1600's, you're not running out of available fuel so adding an AIC would be a waste of time. You really just need to tune the thing. I'm guessing that you have a datalogit (to make the necessary changes in the PFC to run 1600's you really need one.)

Wait a minute.. your mod list didn't include an aftermarket computer. Are you trying to do this with the stock computer? If you just wired up 1600's with no resistors to the stock computer you could have blown the secondary injector drivers.. That might explain a bit.

 

He said he has a Power FC

 

I'll go with everyone else.........tuning? Adjust the fuel curve.

 

My bad.. hadn't had coffee yet.

 

First change the injector sizes and turn off seq operation in the PFC. Then did you wire resistors into the wireing harness for the 1600s? You ned to do that for a PFC. You also need a fuel pressure regulator, please tell me you have one of them. If you have all of these hooked up properly, then your problem can be tuned out.

 

OK guys here it goes from the start..

My car hesitates at 4000 rpms... its like fuel cut... I tried adding an HKS AIC but with the AIC it becomes rich without it it leans out.. Have come to the conclusion for some reason the ecu is hitting fuel cut.. Following are the things i have tried

Rebuilt Motor
Switched to single turbo (did'nt help same hesitation.. switched back to twins)
checked all the grounds (all connected)
Disengaged double throttle (did'nt help)
Installed HKS AIC to give more fuel
Switched to stock ecu ( did'nt help.. switched back to Power Fc.. still the same)


Ok my car had the same mods before this problem started.. My car used to run fine until one day my engine blew.. but till that point the car used to drive great.. so i had a rebuild done and this fuel cut(hesitation) problem has developed since then.. So i can rule out that the power fc needs tunning as it was working fine with the same mods before the rebuild... all i tried new that would have needed tunning was 1600cc injectors.. but i have taken them out and am back to 850cc..


The only two things my mechanic says are not working as they should are

1) the coolant level sensor.. its not working and is disconnected for now
2) The OMP .. the mechanic is of the opinion that it is not working properly so i am using premix now too with the OMP still connected.. the knocks have gone down..

Can it be that the OMP is malfunctioning and giving some bad reading to the ecu and hence the Fuel cut??


What do i do... i want to burn the car down... My SR20DETT and 1JZ-GTE are both here.. but my mechanic and I both want to see the rotary up once again...

Please help... i am leaving for the states tomm. should i bring the Power fc with me have it checked..


Please help

thanks..

 

are you sure its not your fuel pump failing?

 

i agree, that is something you might wanna check
also, double check fuel pressure

 

limp home mode

 

Forgot to mention that i have changed the fuel pump too.... I am using a Walbro 255 lph...

I also feel that the car is in Limp home mode but the question is y?

I am leaving for the states tonite.. Shall i take my power fc with me to have it checked... although the problem is the same if i use the stock ecu or the power fc..

thanks

 

you actualy did mention that you are using a walbro fp in you begining post. i would still check it though, just because its new does not mean it has to work perfect.

 

SO did you ever have the PFC tuned???

When you say hesitation.. Is it like breaking up in the upper RPMS??
OR is it litterally falling on its face, then Back on, and fallin on its face??

and when you are hitting your hesitation, what are your INjector duties???

IF your symtoms are like its breaking up in the Upper RPMS/Boost..
You probably running way to RICH, and need to tune fuel out..

goodluck

 

Oh yea..

did you upgrade your fuelrail and regulators??

you can't just pop in 1600 injectors.

 

It feels like a fuel cut... I am at the moment out of station right now.. does any one have a coolant level sensor i can buy in Long Island?

thanks