Guys,

I have been having 2 different intermittent problems with my 03 / 04 STI.

Mods

TBE, Walbro & Tune (ASG)
HKS dry pod filter
Lowered

I have done plenty of searching but I can’t seem to find anything that is specific to my exact problems. I have had enough, and wanted to check here to see if anyone can shed any light at all on both of the issues I have, before I go spending any money on parts / labour.

Both these problems are intermittent and I cannot say that they happen after anything specific. I.E Car being hot / cold, weather condition or the current Moon phase. They do not happen at the same time or on the same day, they are totally separate of each other.

Issue #1

I Unlock the car with key fob, key in ignition (key light on dash goes away, other dash lights light up), punch in the Brant code, CEL lights up, can hear relay / relays clicking on Brant module inside dash, fuel pump primes (5 seconds), turn the key to start, just turns over, after about 4 or 5 seconds, I try again still no start. Lock the car whilst inside, open it again, try again, and away she goes. But when this happens the CEL light stays on? I can sometimes smell fuel dependant on how many tries I give her, before she starts.

I have tried to get the code buy using my ECU data scan, but it says there are no codes? The CEL goes away by itself after 5 starts. I have taken it to Subaru Ozzy Park when the CEL light is still on to get the codes read, but they said there were no codes up either, current or stored.

This issue would probably happen 1 in 15 times I try to start the car. Everyother time its fine.

Issue #2

Driving along normally within speed limits, slow down, begin to come to idle, get to idle (800 rpm), revs drop by about 300 rpm to around 500, car feels like it is going to stall, kind of. CEL comes on, couple of jabs on the loud pedal and it comes back to life, albeit with some hesitation initially. Again clears after 5 starts, and once again no codes.

This issues probably happens one a month.

So what I have done to try to fix the issues with a fair amount of reading, on here, rexnet,nasioc, iwsti, etc. I am not sure if both these items are related, seems weird that it throws a CEL with no code???

1. Clean IACV - It was pretty dirty - No change both issues still there.

2. Clean MAF numerous times - No change. I have also Disconnected the MAF, try to start, starts ok but CEL comes up, manage to get MAF code for CEL using ECU data scan (whichever one it is, I can’t remember now).

3. Do the DIY Brant solder of the module under the dash. Could not really see anything wrong with the solder joints that were there, but touched over the points in the DIY anyway - No change.

What Subaru told me.

Subaru told me to change out, remove or replace the Brant as this was causing issue #1. However the no starting issue so I have found by research normally is related to the fuel pump not priming? I hear the fuel pump prime and can on occasion smell fuel, quite strongly once it has failed to start... Not sure what my insurance company would think of my car Brantless?

Subaru then told me the MAF was the culprit for issue #2. If it was MAF related would it not cough and splutter more as I am going through the rev range, not just at idle?

What I have found.

If the car does not start after the first few turns over, I lock and unlock the car, try again and 9/10 it starts that time. Does my car have a separate immobiliser to the Brant system? Wonder if it could be this, if it does have a spate system that runs off the key fob?

Apart from that I am lost as what to change first, so I was wondering if anyone else has had these same problems? I am not sure if they are related or not? Seems weird that both throw a CEL with no code?

Any information would be great as I don’t want to go spending money on parts if I don’t need them

Apologies in advance for the massive post, but I wanted to get as much info down as possible.

Cheers guys

Simon