MY94 WRX problems with matrix,ecu, grounding etc etc etc etc etc..!! PLEASE HELP ME!
 

I hope someone can help me before I resort to a box of matches a can of petrol and a taxi to the EVO garage!

My heater matrix went on my MY94 imported wrx so I decided to replace it myself; I have little or no knowledge of mechanics!

Took me about 19hrs but eventually I did it, since then I have had few associated problems, when I go to go round a corner (not always) the engine cuts out! I searched past forums and found that this could be a grounding problem, so I put in various extra grounding cables but this still happens.

Also there is a loud whirring noise coming from the turbo area, the dump valve doesn’t sound as nice as it used to and the car doesn’t seem as quick in the higher gears.

Boost gauge is all over the shop, this may be because I was a bit rough with it when mounting it in the dash, could have damaged it?

I cleaned out the waste gate solenoid with brake cleaner and cleaned the dump valve

As the car was disconnected from the battery for about a week the ecu would have reset, but I did a manual reset using the green / black cables and it showed as having no faults.

Could the problems im having be because I reset the ecu and its just learning everything again before it performs as normal?

My next plan of attack would be a new MAF sensor, as I read that they can go over time and the ecu learns to get over it, to an extent, and as the ecu has been reset it will have forgotten this issue!

please help me im beginning to loose faith, this Impreza has been the most fun car I have ever had and don’t want to give up on it just yet!

Oh, nearly forgot, the rear driver’s side indicator no longer works; it’s not the bulb!

Thanks!

:cry:

anybody?..... c'mon theres loads an loads of you out there that are fountains of information!

Check the earth on the inlet manifold, this is the one for the ECU. Mine was loose once and I spent ages trying to track down the fault.

Is the indiacator related to changing the matrix.

Also sounds basic but make sure the battery is attached firmly

ill check that earth in the morning, for some reason the indicator started working again this evening!??!!

not a bad idea with the battery either!

thanks for your ideas!

I,ve put in 7 more earthing points from the battery neg to - left and rights struts, right manifold, left and right chasis, ecu bracket, steering collum..... still cuts out when coming to a holt, going round corners (not all the time)

have cleaned maf sensor to no avial

still nasty noise coming from turbo area!????

any ideas any one!?

If your electrical problems have all started since you replaced the matrix, i'd be having the dash out again and cheching for any trapped or broken wiring.

you have connected the test connectors (green and black) near the steering column under the dash when reinstalling the dash by accident have you?

Simon

yeah, sorta thought that but dont like the idea off taking it off again....it was a proper mission! but thanks for the advice, wish i could afford to pay a garage to do it!

no mate, i didnt find them till i had done the matrix and reinstalled the dash, then i did connect them to do an ecu reset and fault finder (which came back as having none!) but then i disconnected them again, thanks tho!

oh damn.. would have been nice had it just been that.

too rite!

my boost gauge is all over the shop, dont really understand it all that much to be honest, and my dump valve no longer makes that lovely woooosh noise! ...its just not the same!

advice to anyone who needs to change a heater matrix .... DONT! join the in and out hoses together and bypass it, put another jumper on!

if i take my car into my local friendly subaru dealership and they plug it into their magical diagnostic machine will this give me an exact cause of my problems!???? does anyone know how much, roughly, this service costs!?

thanks

If it's a simple sensor fault then a diagnostic machine should highlight the problem.

If it's more than that - a damaged loom , or short to earth, for instance - then you may struggle to get an answer from just plugging in a machine.

okay thanks, would the dioagnostic machine pick up the same things that we can, using the plugs under the dash and watching for flashing codes!? if so, it should then just come up with none, as it did when i checked myself!?, thus be a waste of time and effort!:confused:

anyone else want to give me their much valued opinon!?

Still think it's ground related, not so much lack of but maybe loose somewhere. As mentioned earlier the ecu and sensors all ground to the manifold, the manifold could have a good ground but the wires from the ecu to the manifold could be loose. Have a good look around and try to recall all your steps incase there is something you have forgotten.

Did you split any connections to remove the dash? check they are all back together properly. You could also have a pipe leaking which would give you the boost problems, idle problems and the strange noises.

Where abouts are you?

im in peterborough.... i do think the best thing will be to take the dash off and double check everything again!

im going to buy a new, easyer to read, boost gauge today so should be able to see exactly what the boosts doing!

i had a quick look to check for leaking pipe but couldnt see anything, and as it only seeems to make its strange noise when its on a decent run, not in shorter bursts that it couldnt be a pipe as it would do it all the time? (probly wrong but just makes sense to me) the nosie does sound like the turbo spooling up but more so, and when you depress the accelerater it goes away but there is no lovely woosh from the dump valve!

thanks for your advice!

bttt