Air Fuel problems

[MidgetNmyGst]

I have a 97 eclipse Gst with evo III 16g turbo, walbro 255lph hp , adjustable fpr, 650 cc injectors. My car is running very rich, And spits and sputters bad when im at full throttle and hit 4k rpm. I know im running very rich because i have a air fuel gauge. I have tried adjusting the fpr, Adding more boost,checking for boost leaks...also idles high when hood is shut ( about 1500 ) but normal when hood is open. any help would be great ive had this problem over a year.
P.S. car was running rich before I added the injectors and it ran fine with the fuel pump before all this.

 

[1995gsx20g]

what are you tuning with?!?!?

ive done evo 560s on a stock ecu and it ran "ok" at best.

at least a safc or better dsmlink is needed to control that size of an injector.

 

[MidgetNmyGst]

At the moment I dont have anything to tune with. However it was acting like this before i installed the injectors.

 

[jrohner]

If you have nothing to tune with, how can you expect it to not run rich with bigger injectors? The ECU is told what size injectors it's controlling, it doesn't just magically know. It's rich because it needs less injector pulsewidth to get the same amount of fuel. Basically, fuel injection does what it's told, and you haven't told it to do anything different.

Also, if you're using one of those "rich stoich lean" narrowband gauges, they're useless.

 

[1995gsx20g]

we can't diag your problem like this.

put things the way they are supposed to be then we can start diagnosis.

 

[EclipseTical]

As others have stated we need more info...

What type of Air/Fuel gauge? True wide-band (AEM, LM1, etc) or blinky A/f narrow band useless crap?

You have injectors and a pump that are significantly larger than stock with admittedly no type of tuning. At the very least you need an SAFC, though with 650s you'd be close to reaching the limit of tuning an SAFC. Personally i recommend DSMLink but there are other options available if you do some research.

There is a reason why the upgrade paths on this site exist, and a reason why we always recommend having the proper supporting mods. Your ECU is firing 650s thinking they are 450s and is dumping a shit-ton of fuel.

Proper Preparation Prevents Piss Poor Performance.

 

[rEclipserGST]

As others have stated we need more info...

What type of Air/Fuel gauge? True wide-band (AEM, LM1, etc) or blinky A/f narrow band useless crap?

You have injectors and a pump that are significantly larger than stock with admittedly no type of tuning. At the very least you need an SAFC, though with 650s you'd be close to reaching the limit of tuning an SAFC. Personally i recommend DSMLink but there are other options available if you do some research.

There is a reason why the upgrade paths on this site exist, and a reason why we always recommend having the proper supporting mods. Your ECU is firing 650s thinking they are 450s and is dumping a shit-ton of fuel.

Proper Preparation Prevents Piss Poor Performance.

+2
I like that blunt, way to pass the torch. Nothing else needs to be said until the OP changes his setup or responds with more info.

 

[MidgetNmyGst]

OK, so i went to get the car tuned last week and its not the air fuel ratio. as it is perfect when it is cutting out . im now thinking its ignition breaking up. Ive replaced the coils ,ignitior , plugs plug wires, battery , battery terminals, battery grounds, and tried 2 differet ecus. im using a apex I power fc .the car cuts out at 5500 rpm . im thinking maybe its a wire on the engine harness? the car is reading only 13.1 volts when started and can be hard to start at times acting like i have a low battery but its brand new and charged.