tbi lean..
 

so after getting my new tbi set up running finally its running lean, when i let off the gas like coming up to a stop and push the clutch in it will die followed by a long crank... after re start it runs ok, meaning i wont die agian until i do the same thing agian. now with the o2 unpluged (open loop) it will not die when pushing in the clutch even at 4k, it will just slowly come back down to idle like it should. but with the o2 unpluged it doesnt run so hot while cruise, here is my set up: toyota 20r engine, gm 2.8l TB, 3 wire heated o2, computer is doing all timming but no knock sensor (cause it would never work right..) fuel pressure is 10psi, please help me with this being lean, its not so fun to drive like this. thanks guys

Re: tbi lean..
 

I will say not OL but in "limp mode". Could be failure of fuel pump. Last fall my mechaic checked my FP buy determining the flow of fuel into a beaker.

Have you thought of doing a datalog and check BLM values? Underlying tune may need to be addressed.

Re: tbi lean..
 

fuel pump is new and rated at 35psi, ill check the blm tonight

Re: tbi lean..
 

Make sure the map sensor is really hooked to manifold vacuum
You probably need to get an adjustable fuel pressure regulator, it'll aid you in tuning it.

Re: tbi lean..
 

i moved map around, from back of the tb to on the intake manifold, still didnt change anything. ill buy a fuel pressure regulator, what pressure are you running?

Re: tbi lean..
 

GM tbi run on pressures at 9-13psi, your application is custom, so you'll have to increase it in steps. I think you can go up to 20psi, depending on the regulator.

Re: tbi lean..
 

So have you seen a vacume regulator, any good? or should i just get the standard adj regulator

Re: tbi lean..
 

you can only use a VAFPR if the definition file supports it(BPC vs VAC). Otherwise a stock GM spring is 9-13 as stated. top down solutions sells a 10-20 or once did.