Hey i am desperate for help. my 03 evo 8 has started going lean wot, afr is 18+, i have changed plugs, fuel pumps, checked the FPR, MAF, Fuel Lines, going to check the injectors tomorrow. anything helps

build:
2.4l stroker
4g63 Head
4g64 Block
OEM 4g64 Crank
Wiseco HD Pistons 9.7:1
MAP Steel Rods
Buschur Ported 65mm Throttle Body
Buschur Ported Intake Manifold
Cosworth Head Gasket
Gates Kevlar Timing Belt
Balance Shaft Deleted
MAP Headstuds
AEM Timing Gears
MAP Oil Cooler
HKS 280 Cams
FIC 1000cc Injectors
Aeromotive FPR
AEM Fuel Rail
Walbro 450
Precision 6262 DBB
Tial 44 WasteGate
Tial Q Blow Off Valve
TTR Intercooler
TTR Exhaust Manifold
AMS High Flow Exhaust

 

wow don't go WOT until it is fixed. that is super duper dangerously lean! sounds like a fuel issue. Let us know how the injector check goes.

 

Hey i am desperate for help. my 03 evo 8 has started going lean wot, afr is 18+, i have changed plugs, fuel pumps, checked the FPR, MAF, Fuel Lines, going to check the injectors tomorrow. anything helps

build:
2.4l stroker
4g63 Head
4g64 Block
OEM 4g64 Crank
Wiseco HD Pistons 9.7:1
MAP Steel Rods
Buschur Ported 65mm Throttle Body
Buschur Ported Intake Manifold
Cosworth Head Gasket
Gates Kevlar Timing Belt
Balance Shaft Deleted
MAP Headstuds
AEM Timing Gears
MAP Oil Cooler
HKS 280 Cams
FIC 1000cc Injectors
Aeromotive FPR
AEM Fuel Rail
Walbro 450
Precision 6262 DBB
Tial 44 WasteGate
Tial Q Blow Off Valve
TTR Intercooler
TTR Exhaust Manifold
AMS High Flow Exhaust

 

What type of fuel?

We ran Q16 on FIC 2150cc and IDC2000

Had to switch to twin 450 fuel pump and Siemens 2650cc injectors....however we were around 13 AFR at WOT

 

What type of fuel?

We ran Q16 on FIC 2150cc and IDC2000

Had to switch to twin 450 fuel pump and Siemens 2650cc injectors....however we were around 13 AFR at WOT

 

How does the car drive power wise? Could it be a faulty a/f ratio lambda sensor? Injector duty cycle? Probably maxed out.

 

currently on 93 pump, and forgot to say I tosses a new o2 in there, compression is 190 across, did a boost leak, and injectors running around 70-80%

 

Checked the hose going to the fpr? I found that if the afpr gets adjusted too loose then afrs go super lean. Try tightening the afpr screw a little and see what that does

 

the pressure on the fpr is reading 43 across the board, give or take a few

 

uhhhh.....

was it fine and now all of a sudden its gone lean?
or did you just get it together and its always gone lean.

 

43 at WOT?