Ok. I just finished my 6 port turbo swap on my S4.
The car idles better than ever but when boost kicks in the car go quiet and then a loud bang as I let off the gas.
Up until boost the car drives great.
I'm using the N341 ecu, N318 boost sensor, and N318 afm.
I found this in the archive and was wondering what it meant.

"Pin 3D is for the fuel pump resistor/relay on turbos, but is unused on manual NAs. However, on Automatic NAs, it runs to the inhibitor switch. But lets face it, no ones converting to turbo and using an AT transmission . So the wire at this pin can really be ignored in most cases. "

RotaryRocket88 said this back in 09.

Idk if he meant to ignore it or reroute Pin 3D.

 

I'd see If I can get a N332 or N333 Ecu.
That 341 is JDM.
Question: which harness do you have on the car?.NA or TII engine harness.
Was the car originally an N/A?

 

Ignore the pin, if your using the na harness you need to cut or re route the knock sensor. On your na harness IIRC goes to your steering but the same wire on a turbo is knock sensor. Hope it helps

 

I'm using the NA harness and yes the car was NA.
N341 is the 87 j spec vert.

 

Ok. I'll just cut the wire since my power steering has been removed.

 

is your bov vta?... It might just be the extra fuel popping in your exhaust, my old turboII did tht after i installed a vta bov.


VTA- vent to atmosphere

 

Yes my BOV is VTA but I can't hit boost at all.
As soon as the gauge reads anything over 0 it just boggs and popps.
I ordered a N332 ECU just waiting till it comes in.
I can get it up to 5k as long as I'm still in vacuum.

 

im not sure if you have to rewire the fuel pump cuz people say something about how s4's are already hot wired or whatever they call it.. i always just rewire it myself when i install a fuel pump..

fuel pump rewire

i just run mine to a switch and turn it on... im not worried about fuel economy or any of the other safty stuff... not much of a hassle

 

Hmm. Ok if the N332 ecu doesn't fix my problem I will definitely be looking into this.
Plus I like the idea of the manual switch to operate as a deflood switch.

 

I'm not surprised, the N332 ECU did not fix the problem.
I'm using S5 LIM and UIM with S4 hybrid turbo and S4 electronics.
Greddy BOV and AEM Tru Boost Controller with 3 in downpipe to straight pipe.
BAC is blocked off, TPS unplugged, OMP blocked off, IAT unplugged, N318 boost sensor, with 660cc Greddy injectors all around.
I took a peak at the fuel pump and it was dark green indicating that it is a T2 fuel pump.
I cut pin 1R, 2K, and 3G since I'm using the NA harness.
With the TPS plugged in the car won't even idle.
IAT is unplugged because the throttle body elbow insert for the sensor is enlarged since the previous owner was running Haltech.
Same situation where the boost gauge reads anything over 0 the car sputters and popps very loud.

 

I've also regrounded the harness according to Aaron Cake's guide and same symptoms.