LLL

I've recently had a problem with my boost limiting itself to 0.5 bar so following a number of searches on the forum, the first place I looked was the boost solenoid valve.

Before cleaning it out, I put the car into check mode by connecting the green connectors under the dash and I could hear the solenoid valve clicking, although it was queit and slow, unlike the other solenoid valve in the centre of the engine bay which was fairly audible (don't know what that ones for!).

Took the solenoid off, cleaned it as suggested with brake cleaner and saw some mucky oily residue come out. Put the solenoid back on the car and now it doesn't make any clicking noises at all, although if you get extremly close to it, you can hear movement inside the unit.

My basic question is, should i definitely be able to hear the solenoid clicking, and if yes does it sound like mine is knackered?

One other question - what is the best way to do an ECU reset on a 2003 WRX?

Any help or advice on what to do / lok at next to solve the boost problem would be greatly appreciated.

Cheers,

LLL.

dan83590

You should also clean the associated Boost Solenoid pipework. On my classic the pipe from the bottom of the BCS has a restricter in it. This can also get blocked. Try pulling the pipe off and take it for a quick drive, boost levels should go sky high so be careful but this test could highlight where your problem is. If the pipe is at fault try cleaning it in the same way.

LLL

taken all the pipe work off and given them a clean but they were pretty clean anyway.

If I wanted to proove (or rule out) that there is a problem with the boost solenoid which if any pipes can I remove to allow me to go for a short & careful drive to see if my boost will hit more than 0.5bar?? Is this advisable??

Cheers

Scott.T

iTrader: (2)

the one on the actuator...
this will prove you can boost but it won't rule out the fact that the ECU may be telling the boost control solenoid to do nothing or the ECU/wiring may be at fault.

dan83590

I think the first thing you should do then is have the ECU checked for fault codes as it sounds like the car may have put itself into Limp Mode. I can't say I'm to sure enough to advise you of how to pull codes from a 2003 WRX. However at this stage I wouldn't go removing any pipes to test the Boost Solenoid as this may cause more damage. Are the rev's also limited? This is another indication of Limp Mode.

dan83590

PS. Sorry Scott, we must have been typing at the same time!!

LLL

I had the car checked for fault codes and the only one it brought up was the cam angle sensor but I can account for this as I took it off when doing an oil change a couple of weeks ago.

The revs aren't limited at all - the car seems to be running fine, ie. good idle, not lumpy - it just won't boost over 0.5psi.

Should the solenoid be making a clicking noise? Its funny that it was before I cleaned it out, but now it doesn't, althogh like I said, if you get close enough to it, you can hear some movement inside the unit. Could it be a case of the solenoid operating but not correctly,i.e. not sealing (or whatever its supposed to do - i'm not actually sure!!).

LLL

I meant to say also that the car was fine last week when driving home from work, I left it on the drive for about 40 minutes then when I went out in it again, it had lost all of its power!!!

dan83590

I would rule out Limp Mode first by reseting the ECU. Also try what Scott suggests. Both these are free, no need to buy parts just yet..

Just a thought, could the BCS still have a residue lodged inside?

grahamfrary

You might have had the green leads connected, but have you actually reset the ECU? If you're still seeing a fault code, then I don't think you have. See How to re-set your ECU unit.

LLL

I've been reseting by disconecting the battery for 30 - 60 minutes. I've looked for the connectors described but i've hit a problem. I have the 2 green connectors, and only 1 black connector. There are 2 single black cores which have been taped up at the end and I also have a single white connector (a different type to the single black connector). I've had a very thorough look and i'm certain there are no other connectors hidden away.

As you can appreciate, i'm a bit confused by this so i've stuck to reseting by disconnecting the battery. If anyone can shed light, it would be great!!

dan83590

https://www.scoobynet.com/general-te...ighlight=reset

dan83590

Or this.

https://www.scoobynet.com/general-te...ighlight=reset

LLL

Fixed the problem last night. Took all the pipes off and gave them another clean through and as I was going to drop the bonnet I thought i'd just visually check the MAF sensor. Found that the little 'bulb' inside the sensor had a thin coating of oil on one side of it so I cleaned it up, removed the battery for 1hr, then took it out for a spin and hey presto, 1 Bar!!!!

Thanks for the help and advice.

dan83590

I expect it was the disconnection of the battery that sorted it. The MAF shouldn't have oil on it though, what type of filter do you have? If it is an oiled type it may have too much oil in it. There shouldn't be so much that it is pulled through to the MAF. Nice to hear that you've fixed it.