Am I wrong to want an Impreza?

Surely you don't need to get it on the RR to find out what's going on? You just need to get in contact with a mapper, maybe someone who travels like JollyGreenMonster, get them to plug in their laptop and find out if it's been mapped etc? I think Bob Rawle doesn't live too far away from you either...

I can check the error codes etc on the car, but if your CEL isn't coming on at all, then you need to get it properly checked by someone who maps.
 
I will have a chat with you on msn about it later mate ! That what GRD said, no CEL so they cant plug there laptop in :(

Maybe this is just an excuse to hammer my credit card to get some more ponys ;)
 
Thing is plugging in the laptop can get the readings from the sensors, so they can see if anything is a miss there. But ok I'l chat to you on msn about it, and no you can't spend more money on your car, because you're not allowed to be faster than me :p
 
Out of intrest if this is a map fault then why has it just suddenly started to give me problems, ive done 5000 trouble free miles and i have not changed anything :\
 
May not be something wrong with the mapping, but by checking the map, you can see where the boost targets etc are set to, thus being able to tell if it's been tweaked. There could be a sensor which has gone wrong, which hasn't thrown a fault code yet, which can be seen by monitoring the ECU reading via laptop. oooooooor your Idle Control Valve is dead up!
 
Any cheap places to buy subaru parts off the web ?

For example, Autovaux for vauxuall parts etc Might just buy and idle control valve for the minute
 
Sam said:
I will have a chat with you on msn about it later mate ! That what GRD said, no CEL so they cant plug there laptop in :(
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There are some codes that get logged but don't throw up a CEL. Usually they're OBD codes which is handy because you can read them with a generic OBD scanner.

Might be worth investing in one of the Tactrix USB -> Subaru cables and a copy of ECU Explorer (which is free) then you can do your own diagnostics. I'd lend you mine but I sold it to a bloke in Bristol after I got rid of my Legacy.
 
You don't necessarily need to get it on the dyno to find the fault.

Basically what you are lookin for when plugged in the laptop, is the load zones the MAF sensor gets to when on boost, a keen eye will pick up whether the load zones are in the right ball park.
eg and old UK classic (the one most susceptible to MAF failure) with basic breathing mods should get to around 50 peak load.

A car only reaching 30 load for eg will make the ECU give less fuel and more ignition timing. ! however that 30 load is still a legitimate load figure (hence why no CEL)
The only thing the ECU can "feel" is the engine Detonating via the knock sensor and thus retarding timing and adding fuel back in as safety measures to try and save itself.

I've yet to see a new age car with a faulty ISCV so please stop guessing what's wrong and put your efforts toward organising it to be looked at by a specialist.
 
ScoobyDoo69 said:
Surely you don't need to get it on the RR to find out what's going on? You just need to get in contact with a mapper, maybe someone who travels like JollyGreenMonster, get them to plug in their laptop and find out if it's been mapped etc? I think Bob Rawle doesn't live too far away from you either...

I can check the error codes etc on the car, but if your CEL isn't coming on at all, then you need to get it properly checked by someone who maps.
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As you stated, if there i no CEL light there's nothing currently faulty.

The ECU does have historic codes as well as current codes so checking them to find you have a whole list of stuff in there will get you in a right pickle.
Someone could have unplugged a sensor 4 years ago, got a CEL and never had the ECU reset. So you'll be thinking you have a fault when you dont.

It doesn't have to be a mapper (but generaly that sort of peson is more clued up than most) most specialsts will have equipment that can acess the data via the OBD port. (Subaru has a box called the "select monitor" for eg)
 
Another thing is that if you had it mapped on a failing MAF sensor (if it turns to be that at fault) you will need to get the map checked anyway for safetys sake if nothing else.
 
Hi Mate

I personally dont think its been mapped, the previous owner had it for most of its life and didnt mention anything at all ...... Your saying take it to a specialist which i have done but they have just said i need to take it to the RR ... They have a mapping session on tuesday so they said i could bring it down then and then just pay £50 for the RR session

This would be at surrey rolling road
 
Only just read the posts about GRD..
Sounds like your best option then.
Could be something simple like a lambda sensor getting lazy to a fuel pump dying.
A rolling road session with all the gear attached to it will tell you a lot more about what it's doing.
 
Hi

Thanks for all the advice guys :) Another thing, jus went outside to start the car up and the revs instantly started going up and down without me touching anything (i thought previously that it only started doing it once i drove on boost)

Cheers
 
my car did this

turns out the air mass meter reading was all over the place because of a boost leak which in turn was throwing the AFR out.

Not sure if this can happen on the scooby though ?
 
That would show up as a rich mixture on boost and hunting at idle yes, Imprezas have the same sort of issues.

Basically the MAF sensor reads the correct amount of air and fuels according to that reading, then due to the leak, some of that air escapes, so what's left that gets sucked into the engine is over fuelled.

If it's lean, (and the issue is still an air leak) the leak has to be on the inlet side of the turbo (no pressure created there) Air is sucked in, missing the MAF sensor completely and thus the lower MAF reading will result in the ECU delivering less fuel and thus a lean mixture will result etc etc
 
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I took the live off the battery for a while too and poked around all the connectors. Left it for 30 minutes fired it up and now it seems ive got an engine warning light :\ Im going to get it booked in for a rolling road on tuesday to see if that throws up any issues
 
You know you can read the CEL codes yourself by connecting up a wire under the dashboard, right?
 
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