Microtech 4AGE 20V running super rich!

[Jechz]

Hey all have had a problem with my ae86 overfueling for a month or two now. Long story short i bought a 20v ST with ITBs from another 86 and slapped it into mine. Only thing that was unknown to me was the fuel setup of the other 86. It came with a microtech ecu already tuned for the motor, its all installed now. I ended up doing the 4age intank + Vl pump + surge tank. But nothing changed.

The fuel economy had been pretty bad like at best 200km from a full tank of 98. Iv rang up a few tuners they all want $800 - $1000 to fully retune the engine, trying to avoid this as dont have the funds atm. Hard to believe that it was running pretty well in the other car but really severly overfueling in mine, not blowing any black smoke what so ever. AFR is sitting at 11-12. Likes to back fire alot out of the Itbs.

If you guys know something that might help let me know, cheers.

[Matt]

How is the fuel pressure reg? Was the alternator working previously in the other car?

What do your plugs look like?

Tuning realistically is the only way to fix it.

[LittleRedSpirit]

Buy a widebank kit and install it, data log the car and tune it yourself.

[Jechz]

The alternator was working, the plugs are pretty fouled/black.

Not sure about the fuel pressure regulator, i heard they regulate up to 40psi. Are you meant to install a aftermarket FPR considering my fuel setup?

[Matt]

High fuel pressure will squirt more fuel in, same with increased voltage from 12 - 14 with a working alternator.

Decrease your duty time and run it leaner. But your prob best off spending the $ on a tune

[tan18d]

I had a microtech and ended up putting a haltech in. It has more tuning points which suits the 20v with ITB's for a road tune.