down to the wire,still scratching my head

[redbaron]

I have been beavering away on my impreza for a while now,came to me a rough running dog,misfire,leaking oil/water to name just some of its issues,2 weeks ago i thought i had got the better of it a brief roadtest seemed to confirm.However this didn't last very long pulling briskly away from a roundabout it suddenly lost power and cut out.Pulled over managed to restart but was very very hard to keep running.I limped home and could see that it was running very very rich at idle and is leaving a pool of black sooty crap on the floor,a lot of it and it will kill the engine dead if left idling.Have checked fuel pressure reg,oxygen sensor,air flow meter,idle control valve,fuel filter,air filter,water temp sender,i have also disconnected the map sensor nothing i do seems to get it to lean off!
It has a basic self diagnostics on the ecu and shows no fault codes,but disconnecting any of the above will show a fault so probably not ecu.
Any opinions welcome i am running out of options and time,no budget for pro help or the like have checked scooby forums but not found any new clues!I have a box of matches ready as a last resort!

[rjudgey]

could be dodgy turbo maybe the spools shaft has broken which does happen occasionally and would explain the running rich and no power all the time.

[924]

I know nothing about Scoobies but just found this after a search on Google, posted about an X Reg Impreza. Might be nothing but you never know (I've tried to pick out the relevant bits).

First Post...

Hi
I have a 2000 X reg Impreza turbo in at the moment, which is running extremely rich. The fault just happened as the customer was driving 'normally'. The car died as it choked itself to death.
It stood at my workshop over the weekend and started up first time this morning. Although they do have a tendency to run rough at idle, it was very apparent that it was excessively rich and has left a large black soot patch on the wall. I can verify that there is no fault codes stored. So no live data to view. The car has been 'de-catted' some time.

Final Post

As there could only be a handful of items causing such a problem, I was investigating the air intake system, which appeared to be robust and in very good condition, although I did notice that there was a part deliberately missing, perhaps a dump/return valve of sorts.
The end going back to the intake side of the turbo was blanked off with a purpose made alloy blanking stopper and on the inlet pipe just before it goes to the throttle body the end was open to atmosphere. Obviously the pressure had forced the plug out. Now replugged temporary fix and all seems well.

[tommi]

where is the map sensor fed from? could you be getting boost leak yet the map sensor is still reading boost?

for it to suddenly start happening i would check boost pressure everywhere

[rjudgey]

leaky hose joint or split possibly check everything carefully.

[TeamTotalWankel]

I'm no expert on Subarus, but thinking logically why would the engine be supplied with too much fuel?

ECU thinks the engine's cold - temp sensor?
ECU thinks engine's revving - crank sensor?
ECU thinks engine has boost - map sensor?
Fuel return blocked, so fuel has to go somewhere - pressure regulator?

Hope this helps

[redbaron]

leaky hose joint or split possibly check everything carefully.

would like say thanks to all your input,give yourselves a collective pat on the back as your input persuaded me to try presurising the inlet tract with my leak detector and guess what 100% leakage!Traced to a duff hose clamp,running a lot better now,only a couple of minor things to sort so should make it on friday.
I have had a confirmation email today from Valerie Wicks but the attached confirmation letter seems to have bug "filecure" when you open it anyone else found this and is there anything i need to know other than turn up at 9am?

[Jaffa]

I had to get mine re sent as my pc tried opening the attachment up with Media player

[tommi]

i got no email at all

[rjudgey]

No probs, glad it wasn't my original diagnosis! lol! Sounded familiar though as I had same thing with my BMW 1er which is quite a bit tuned and kept blowing hose off the inlet untill I machined some extra grooves into it and then got some super tight Stainless Jubilee clips round the silicone hosing.
Can't have another one dropping out otherwise won't be much fun and we'll all be done way too early! lol!
Then again if we did finish early could go off up to Donny for cheap easytrack trackday!