I've just got back from having to work long distance.. I've left the car perhaps 3 weeks but my father has been using it to do motorway trips.. he's a careful driver and I trust that he hasn't been doing anything stupid with it..

Anyhow, something has gone wrong, I'm boosting at 0.5kg/cm^2 and my boost gauge doesn't seem to go over that at all. It usually is around 1.3kg/cm^2. Just a bit of background information; running a version 6 WRX STi JDM with custom exhaust and panel filter for the last 7 months with no modifications, had an oil change about 6 weeks ago and generally in very good condition.

The car does not seem to be making any strange noises, there's no smoke and nothing that would lead me to believe that the turbo has broken. I had a look under the bonnet but have no clue where to look for loose wires. I came to the conclusion that the following could be wrong: -

• ECU has limited the boost due to something wrong with the engine.. I did fuel up with 99octane v-power as usual from shell before this occurred so shouldn't be any knocking.
• Leak in the pipes? (sorry for the incorrect terminology) that go from the turbo to the intercooler or to the engine, or however it works.
• Solenoid sensor damaged somehow or dirty?

I'm just wondering if anyone has had any similar issues? My friend is taking my intercooler off tomorrow and checking the air flow; he said he was going to check if the turbo was broken which was as simple as just seeing if the turbine spins.



I'm kind of hoping that this isn't one of those problems that requires me to spend thousands on fixing my car.. I wouldn't have thought that there's going to be any engine damage though, I always wait for operating temperature before driving spiritedly (never red line), and always let the car cool down before turning it off as I have a turbo timer.


Anyone have any comments?

 

I am not saying this will work with yours, but it works with mine,
disconnect the live terminal from the battery for 10 seconds
reconnect.
Mine does it regularly.
it resets the ECU to programmed map, not learnt.

Bez

 

Hey buddy, thanks for the reply, I thought about that and wrote it for bullet point one but wasn't sure whether resetting the ECU state would be a good idea. I figured that if the ECU set it to low boost, it did it for a reason and I should figure out exactly what it is.

I understand that the ECU learns based on driving style and I do realise that I drive like a granny (short distance to work and then motorway driving).. It might be hard to understand why I have a WRX STi but I really love the car and have been a fan of them for years.

The advice is good though, if it does fix it, I'll probably still have a look at what caused it. I do all the servicing myself and although the last service was only an oil filter fresh oil, I didn't bother to check the spark plugs again etc. I mainly just concentrate on changing the different oils regularly as I've never yet had to change a spark plug..

 

Hey, found the issue.. connected the black diagnostic cables together underneath the driver side dashboard and read fault code 23. MAF sensor! I hear they're quite common the version 6 STi.. needless to say, it was dirty :-)

Panic over, back to finding a nice map for it.

 

how did you get the reading?

do you need some sort of device?

 

Hey, to get the reading, you just need to look under the dash and connect the black wires together and turn the ignition on (but not the engine). The check engine light will then flash in a specific set of combinations. I looked up the combinations on the web and identified fault 23; it's all fixed now and didn't cost anything! :-)

 

Scroll down for classics, very simple to do

http://www.scoobypedia.co.uk/index.p...eadingECUCodes

 

mine isn't a classic.

am i looking at some expensive cable needed?

 

Subaru Specialist so