I had a Vortech kit installed recently. I took it out for a spin when it was first done and it was a bit lean high 13's to lower 14's AFR but boosted great and felt nice.
On my way home it went super lean WOT like maxed out the wideband gauge.
We thought it might be the FMU so I just got a new Vortech FMU and installed that. Took it out for a spin and the same thing.

Next I just pulled the fuel pump as I was told that the hose connecting directly to the fuel pump can come loose sometimes. I checked that and both clamps were nice and tight. One of the connectors on top of the fuel pump which I think was for the return line was loose. I latched that back nice and tight.

Took it for another spin and still super lean. I was driving back then nice and easy and afr's jumped to super lean for a moment and car bogged down. Limped home. Parked it. Turned it back on and idled fine and took it for a spin and drove fine but still would go super lean WOT so went super easy on the gas.

What could be wrong with this? What could allow it to be decent at first and then go super lean like this??

Driving me nuts!!

 

This may have to do with the black box...
I know that when I had my comptech, the ESM (electronic signal modifier) which is used to hide boost had one of its lines come loose and anytime I would go into boost the car would go super crazy. I soldered all the connections and wala everything was fine.

 

Yeah could be. I know the wiring was double checked after it went super lean.
I spoke with Vortech and they said to check fuel pressure so I guess I will have to buy a fuel pressure gauge. Would you be able to tell from under the hood at idle revving it up if it's getting enough fuel pressure? I don't want to have to run another gauge into the car to see especially.

Also with your black box thing was it running super lean from the bad wiring? or just stumbling and stuff?

It's weird since it boosted fine at first(a little lean) but still worked. Now just goes crazy lean and boggs down bad.

 

Get a fuel pressure gauge.

Sounds like you are have fuel starvation. My car will do 'the super lean bog bit, when the tank is lower than it should be << i.e. out of fuel, our cars can show 2-3 bars of fuel and be too low to pickup.

I put two gallons in and it didn't help ; I was sure the fuel pump went bad, my buddy went to get two more gallons and that did the trick.

If you have a lot of fuel then follow it from the tank to engine see if there is a dent/kink. Having a fuel pressure gauge really helps with diagnosis.

Could your injector be screwed?

 

Plenty of fuel. Half a tank or more.
Car has been running on the 255 pump for about 4k miles now with no other issues. Everything worked perfectly fine before the kit so seems weird it would go bad just as the kit went on.

 

The gauge will stay in the engine bay. You can tap it right to the fuel rail. I ran a areoquip line from the rail to the gauge try to prevent engine vibrations from killing it.

 

Do you know someone near you with a Vortech kit and can do a part swap diagnosis?

 

Does the engine build boost revving in neutral enough to see if the fuel pressure goes up with it like it's supposed to?

 

Not really sure what there would be to part swap to test.
I had an FMU that came with the kit. I just bought another one thinking that was the issue but apparently not.
Swapping the black box would be a real bitch to do all the wiring. Doubt anyone would want to sacrifice there box to test either haha.

 

What fuel pressure regulator are you using (I am unfamiliar with the stock vortech kit)?