I think something is wrong with my Factory boost solenoid circuit...

I took the WRX for a drive today, When i stopped at idle.. I could hear a weird constant "ticking" noise.. It's not the injectors.. That's a diffrent ticking noise. It's coming from the boost solenoid... I unpluged it (cable, not the vac lines) and the ticking stopped. You could also touch it and feel it vibrate. (It was quite hot to!)

When i unpluged it there was no change to the car at idle.. It still idled ok.

I presume it's being turned on and off in quick succession... Is it swiched through a relay? Or is the ECU turning in on and off directly? It's never done this before. I don't think it should be doing it eigher..

Any help would be great.

Thanks,

Tim.

OK... It gets power (+ Positive) From the "main relay"... It gets ground (-) from the ECU...

But the power also goes to Oxygen sensor and "pressure exchange solenoid valve". I think that connects to the MAP sensor.. It's on the same metal bracket as the Boost Solenoid.

So it could be the main relay, OR ECU... Does that sound right?

OK.. The power from the main relay also goes to the Idle Control Valve.. So since it idles OK.. and drives ok..

Is it the ECU then?


Tim.

stock ecu?

if so, I would be checking the tubes going to the MAP sensor.

__________________

Long live the WRC

when i had a unichip installed on mine the stock boost solenoid used to tick, lift passenger carpet to check what ecu you have or any piggybacks like a unichip

Interesting..

Fully stock ECU.. I know that (i have pulled up carpet before). I have replaced some tubing for the boost solinoid.. Better go do the map sensor stuff. (It gets super hard and cracks)

The car runs with it unpluged (the boost solinoid)... just very low boost levels AND CEL stays on solid...

Thanks for the ideas..

It hasn't started ticking again today while i drove it...

Tim.

OK.. Changed all vac hoses from MAP/ Boost sensor... all the way to the middle of the inlet manifold. Including the "T" pices. Most of the rubber was hard and brittle. Put good quality silicone hose in. I had already replaced the line from the input duct (Before turbo input) to the Boost solinoid.

Unfortunalty.. It hasn't changed anything... After a test drive around the block.. Boost level is fine.. But boost solinoid keeps "ticking" on off, on off, etc...

Any ideas? Maybe replace "main" relay or ECU? They are the only 2 things that control it.

Tim.

its meant to tick

__________________
Too much power is just enough ....

Are you sure? I would think if it was meant to always do that.. It would always do it. But it has only just started to do it. None of my other subarus do it eigher.

I'm guessing this is probably how they get over hot and the glue ends up running out of the top.

Tim

Replaced main relay. No change.. But no surprise there though... I thought it was ok. Pain to get to!

Can you change over the MAP sensor?

__________________
Cheers,

Simon.