thanks for taking the time to read this message... i have searched and cant find much...i am having some fuel problems and here is a list of what is on the car and what is going on with it...

Vortech Supercharger 3.3 pulley
Stock Injectors
Utec
Walbro 255
JWT Oil Pan spacer
Vortech Fuel Management Unit... no return

At first my car was running lean... so we knew it was a fuel problem... come to find out when we first installed the walbro we didnt do a couple of steps according to the TN instructions...we drilled the 7/64 hole in the FPR, drilled the 2 holes in the plastic bottom and popped out the yellow cap...

Now when i start the car it is backfiring... and running horribly rich... around 8.5 at idle then when i put it in drive and give it a lil gas it drops down to 0.3...

The car is shaking at idle and is also at low RPM...

THe driverside exhaust is blowing cool air and the pass side is blowing hott...we checked my plugs and they are fine... they are NGk Iridums 1 step colder...

my question is were the TN instructions on the Walbro installation inacurate or made for bigger injectors? my fuel pressure is about 56psi which is better than what it was when it was too lean (70 psi)... SHould i stop stressing and just get a tune?? any guidence would be great!

 

with the 3.33 pulley why did u get the walbro? The fmu/aux pump is more than enough.

bc u installed the walbro and drill those holes, u arent able to control fuel pressure at idle causing u be extremely rich. I believe now u need a fpr or try to get the utec to lean it down a bit.

 

He is not using the aux. pump.

Im thinking it the two holes that were drilled and the yellow piece at the bottom that was removed.

 

So in other words since i stayed with the stock injectors i shouldnt have installed the Walbro with the Vortech FMU? I thought the UTEC only controlled boost...

 

The Utec controls fuel, timing, ignition, and boost.