Weird fuel problem on my setup
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From: Orlando, Florida
Weird fuel problem on my setup I upgraded my fuel system with -6 braided line supply and return, have a Aeromotive boost sensitive regulator , 50 lb RC engineering injectors and Fast Rails. I already had a Racetronix P&P fuel pump.
Talked to the shop tuning my car, this is what they said was happening..
Under wide open throttle the car was going rich
Under part throttle the car is going lean.
WTF would cause that to happen?? On the lean scenario I was told they were trying to add 15-20% more fuel and it was still running lean.
The only thing I've changed is now I'm running a 2.75 pulley, so I now I imagine my car is pushing 12-13 pounds of boost nothing crazy.
Anybody got any ideas??
Talked to the shop tuning my car, this is what they said was happening..
Under wide open throttle the car was going rich
Under part throttle the car is going lean.
WTF would cause that to happen?? On the lean scenario I was told they were trying to add 15-20% more fuel and it was still running lean.
The only thing I've changed is now I'm running a 2.75 pulley, so I now I imagine my car is pushing 12-13 pounds of boost nothing crazy.
Anybody got any ideas??
TECH Resident
Joined: Oct 2005
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Try not boost referencing the regulator.
Removing the boost reference will lean the boosted mixture as fuel pressure will no longer rise to maintain the pressure differential across the injector.
Removing the boost/vacuum reference will attempt to richen part throttle as vacuum is no longer lowering your fuel pressure.
Experiment with a wide band if you can access one, and with care under boost.
Removing the boost reference will lean the boosted mixture as fuel pressure will no longer rise to maintain the pressure differential across the injector.
Removing the boost/vacuum reference will attempt to richen part throttle as vacuum is no longer lowering your fuel pressure.
Experiment with a wide band if you can access one, and with care under boost.
9 Second Club
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From: Norn Iron
If its boost referenced now, and you havent adjusted the fuel parameters within the pcm, its gona do weird things.
From looking at EFILive, isnt there settings that reduce fuel flow electronically when there is vacuum in the inlet ?
Almost like electronic boost referencing to a degree, while the mechanical side stays fixed. ie the fuel pressure
If you do boost reference your reg, then this table should be adjusted accordingly.
From looking at EFILive, isnt there settings that reduce fuel flow electronically when there is vacuum in the inlet ?
Almost like electronic boost referencing to a degree, while the mechanical side stays fixed. ie the fuel pressure
If you do boost reference your reg, then this table should be adjusted accordingly.
Thread Starter
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From: Orlando, Florida
adjusting the pcm with the boost reference'd reg sounds like a big PITA.
I'm going to suggest what Andereck said and see if that cures the problem.
so disconnect the vacuum source and keep the fuel pressure rock steady at 60 psi and tune from there, that sounds easier.
i dont think the tuner is using EFI live, think he's using edit or hptuners.
I'm going to suggest what Andereck said and see if that cures the problem.
so disconnect the vacuum source and keep the fuel pressure rock steady at 60 psi and tune from there, that sounds easier.
i dont think the tuner is using EFI live, think he's using edit or hptuners.
I don't recomend using the boost reference'd part of the regulator untill it is absolutely needed. I have found for me it was easier to tune and keeps another varable from making it hard to adjust the fuel. I had some of the same problems, but not very bad, when I was running the MSD BAP. If it doesn't help in the tunning process then I would look at your fuel pump situation again. I don't think that is the case, but it could be. Good luck.
all you have to do is make the ifr table flat one value across the board.. EASIER
the slope that it is on from stock is to compensate for not having adj fpr.
if your 'tuner' didnt know that then.. i dunno.
if that is allready done then you could have a big air leak somewhere probably behind the throttlebody.
the slope that it is on from stock is to compensate for not having adj fpr.
if your 'tuner' didnt know that then.. i dunno.
if that is allready done then you could have a big air leak somewhere probably behind the throttlebody.
Thread Starter
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From: Orlando, Florida
I sure as hell hope he knows MM. I'm just trying to do my homework if they don't have it figured out by midweek.
I'm a newb when it comes to tuning, what is IFR mean?
I'm a newb when it comes to tuning, what is IFR mean?
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