The problem
The car does not want to start, and when it does finally start, it backfires, runs really rough and as soon as u let off the gas, it dies.

The project
89 GXL with an S5 TII swap, running the TII tranny with the mazda trix driveshaft.

What Ive done
Just put in an 89 TII motor from a front clip, I am using the J-spec harness, I took the rat's nest out and put block off plates, the car has a walbro 255, 3 inch down pipe, FCD, koyo radiator with electric fan, greddy rs BOV kit, new NGK plugs, new 7mm wires

What I know so far
that im getting fuel to the fuel rail
that im getting spark on leading and trailing
that i have good compression over 100 psi on both front and rear
that the timing is right

 

vacuum lines and piping all kosher? sounds like a air leak somewhere maybe?

 

I put vacuum caps on all but he MAP, fuel pressure return and BOV
Everything else was capped and I didn't hear any large vacuum leaks while running

 

could a leak between the uper and lower manfold cause this much of a problem, their is no visibly gap between the two but the j speck harness does push up on the uper and i didn't use a new gasket.

 

Brake booster line connected to the back of the intake?

 

break booster is hooked up

 

their is a relay or something attached to the TII ecu that the NA one did not have does anyone know what this does?

 

update

its not the wireing harness
its not tps
its not MAF


any one have an idea im running out

 

i installed the knight sport chip and it is running good now