86 RX Sedan , computer issues ?

[discopotato03]

Hi all , I have a thred going at Ausubaru about EFI problems I've had with my L RX Turbo Sedan .

First the mod list .

 

Rebuilt Aus spec XT4 engine/TWE style header/Garrett GT BB turbo/late NA cams/Spider inlet-flanged modified to take 86 L MPFI TB and twin switch TPS . CR is slightly up at ~ 8.1:1 and heads were ported .

 

For ages my car would lose a bit of power initially and come good but not often enought to worry about .

A while back the ECCS would come on at closed throttle and go out as soon as I touched the go pedal .

 

As the mods progressed this mad mode became more noticable and when I got my Tech Edge WB02 going I noticed that the trouble was it would go lean and flash code 35 EGR ground issue .

My engine has the EGR valve and pipe in place but it can't achieve anything because the passage in the top section was choked up with hard carbon . Also the valve body is bolted through a blanking plate to the manifold .

I tried a couple of vacuum solenoids because I thought maybe they'd jammed and the computer could tell this . In the end I didn't have a solenoid plugged in because it didn't make any difference .

I found that Subaru stuffed one of the plug terminals in the engine to body loom connectors so that it had two sockets trying to contact togeter rather than a socket and a pin . It was the black/red ECU control ground BTW and Coxy here removed the factory connector and fitted a six wire weather pack connector .

Problem still remained so I thoght it must bre the brown/red wire which is the ECUs ground switch for the EGR solenoid .

Having looked in the WSM we eliminated the EGRs power supply as a problem - powered up by the fuel pump relay as is the pump and the auxiliary air valve . Cory said power probs show up as blown fuses or smoke/smell dramas .

The abouve mentioned EGR solenoid ground wasn't the proplem as I removed its engine loom connector pin to isolate that section then later cut this wire close to the ECU to isolate the wire at its source . Still got the code 35 and lean mad mode .

Because I'd had the computer out I found that water had got into it at some stage and there was corrosion at the power supply plug (the one with the thick wires and big pins) and more inside at the gadgets up off the circuit boad on the heat sink end . Would these be transisters/drivers for injectors EGR switch etc ?

 

Also something I forgot to mention is that this car never acts up when cold , only after having been driven for a while and more than light throttle used .

We have changed the ECU temp sender and ignition coil to eliminate those as well . Fuel pump was changed out for a Bosch one used in a GM product here that had a Nissan 153Kw RB30ET Turbo engine (straight 6 3L turbo) std .

 

I have someone sending me another computer to try and I hope this solves the problem . The only other thing I can think of was that some of the injector power wires were found to have green corrosion in them when the injector plugs were changed to the finger clip ones .

 

Fingers crossed the water in the computer caused the problem and will know as soon as I try the other computer .

 

Can anyone with a 3 ECU plug RX Turbo (flap AFM one) relate to any of these problems ?

 

Cheers , Adrian in Australia .