P20SPD

iTrader: (1)

Driving home toinight, nice and steady, no power runs off round abouts or anything. 15 mile cruise at 70mph(and yes it WAS 70), off slip road, up to traffic lights for roundabout, and car feels as if it is about to stall. It doesnt, and picks its revs back up unaided.

Set off from lights, steady through next set on round about (100m) next set change red (another 100m), me at the front and the revs drop to about 400, oil presure is about 1.5bar, and it would not pick itself up, so i applied some revs.

The car sounded funny, but then it has because the exhaust is blowing on the manifold and at the bottom of the downpipe.

Drives home from there, another 20 miles, no problem, but almost stalls when i get home (the in laws actually), 400 revs, does not stall, does not pickup.

Whilst driving the last 20 miles i checked for knock on the sensor and on the link tuning module, not a sausage. Checked to see if it was running lean or rich, perfect.

I also depressed the clutch and let go of the accelerator a couple of times, and it did the same again.

Oil temp and pressure, as normal, mid 80o and 6bar, puzzled

The only thing i did notice was that on lifting off the boost gauage dropped to -700 thingymebobs (Defis), now when normally doing this it drops to about -600.

Had my tea, re-started the thing after having a general look around, although the torch was not perfect, no loose pipes anywhere, no sign of oil leaks or anything. Except for my really badly knackered front tyres, wire showing.

So after restarting it did the usual sort of link startup and then ran fine like it normally does. Blast on the throttle and revs settle fine without nearly stalling.

Very, very puzzled

Any ideas?

Spec:
MY00 UK Wagon, APS FMIC, MD304 turbo, 550cc injectors, forge dump valve, Link Ecu, up pipe, full 3" decat.

DuncanG

Sounds kind of like the problem I had recently with a knackered lambda sensor. Symptoms: fuel consumption shot up, rough idling often almost stalling, and very hesitant under light load. Seems to be running a lot better now with new lambda but haven't checked consumption over a full tank yet.

You say your AFR is OK but unless you have an independant reference you wouldn't know if the lambda was on its way out.

Hope your problem is nothing more serious.

P20SPD

iTrader: (1)

Sorry forgot to say the reading on the link module was what i understand to be the norm,from normal monitoring over the last 2 months and from when Bob Rawle was mapping it.

Thanks for the input

Will have to test it tomorrow if i can.

DuncanG

What I was getting at is that if the lambda sensor is starting to fail (but not yet completely broken) the ecu will still be able to run closed-loop (at light loads) but the stoich point will be cocked-up (it will be running ultra rich I think) but your lambda-link or other AFR meter, if it uses the same sensor, will show normal operation.

Appologies if thats all obvious and I'm flogging a dead horse.

Floyd

iTrader: (9)

I'd check the dump valve, try the original instead.

F

hades

I've come across similar syptoms on other cars due to a knackered air bypass valve; these normally let a little bit of extra air past the butterfly on tickover (particularly when cold) as otherwise it wouldn't tick over properly - therefore if it sticks shut, car won't tickover properly. If it's just tickover problems but otherwise runs fine, it could be something like that? Higher vacuum would be consistent with that, lower oil pressure could just be due to lower revs.

Don't know if it works like this on imprezas, as I've never looked. I'm sure one of the experts on here will know if the scoob is set up like that or if I'm talking complete rubbish!

R19KET

I very much doubt it will be the lambda sensor. Bob would normally map the car in open loop, and leave it that way. So, even if you disconnected the sensor, it would make the blindest difference.

I agree with checking the dump valve. It could be dirty, and got a bit sticky.

I wouldn't worry about the oil pressure. 1.5bar @ 400rpm is pretty good, given that the pump is driven by the crank, and pressure is rpm related.

Mark.

Pavlo

for sale, phase 2 idle control valve....

Steve, I have one spare if it turns out to be that.

Paul

David_Wallis

removed offer, as removing injectors

[Edited by David_Wallis - 2/6/2003 2:37:33 PM]

David_Wallis

just thinking about this more, sounds like a vacumn leak..


Jubilee clips??

David

P20SPD

iTrader: (1)

Absolutely no problems since the above dates, except for last night.

Exactly the same problems

Started this morning, drove as i would normally, and no problems what so ever

Think i will do a bit of cleaning this weekend

Do you still think its the same thing? or not?

Cheers

Steven

David_Wallis

ScoobyDuck

iTrader: (1)

my vacume is normally -600 & drops to -800 when on engine breaking, so sounds like vacume is not leaking.
could be idle control valve problem, could be alot of things too! plugs?
all strange that AFR is right tho!!

Steve

MorayMackenzie

Two front tyres down to the wire will earn you an instant 6 points... how are the back tyres? Just wonder if you could qualify for the full 12 points in one go!

David_Wallis

The car was off the road whilst they were like that...

They now have plenty of tread.

so

Jolly Green Monster 2

All four had loads of tread last night!!

Honest..

don't believe the idle problem still exists either does it P20SPD?

Mine was doing similar and I found leak last night on the way home from Leeds... the new downpipe was causing the turbo to come on boost quicker which highlighted my crap boost gauge connection..
It blow the pipe off!! one quick stop in services and a couple of cable ties and sensible length pipe work and no problem (so far).

JGM

P20SPD

iTrader: (1)

JGM, it did it again last night after leaving you and David.

Then it was fine this morning, and tonight!

Jolly Green Monster 2

Oh damn!

Perhaps Pavlo was correct then?

Although a bit weird to be fine some of the time and not others..

But then what do I know.

was intending to reset my ECu but it is cold outside..

JGM

nom

Well. It doesn't seem to like nights. More of a morning car.

Try changing the time on the clock - it might think it's not as late as it is & not do it any more?

harvey

iTrader: (48)

Steve: It sounds as if the problem only manifests itself on tickover and the fact that its intermitant means its unlikely to be a pipe. Suggest you take your BOV apart and look for debris. GIve it a clean and reassemble.

P20SPD

iTrader: (1)

Cheers, think i will do that this weekend. Brake cleaner best to clean it with??

harvey

iTrader: (48)

Oil contaminants in the air stream which form into crud are what you are up against. An evapourating aerosol spray from Halfords or a motor factors is what I have used but I guess brake cleaner will do the job as long as it removes oil.

harvey

iTrader: (48)

Look carefully for debris and what it is. What could cause the piston to stick?

P20SPD

iTrader: (1)

Cheers Harvey

So clena up, and catch can then?

David_Wallis

sounds like a good idea.

Them gaskets wont help either.

David

P20SPD

iTrader: (1)

Dave can you help us create a catch can please?

I know the gaskets wont help, will try and sort it soon.

harvey

iTrader: (48)

A catch tank is a good idea for a number of reasons though it will not totally eliminate the oil vapour in your system.
I have a Cusco which is round and because of my changed layout was not too difficult to locate and fit. It also has a sightglass so you know when it needs emptying. All I ever collect is oily water whereas when I fitted it I expected to be collecting oil which is just not the case. The climatic conditions seem to influence greatly the speed at which it fills up from nothing over a month to half full in a few days.
From memory my tank was £100 plus postage but I could have saved a lot if I had shopped around in the motor sport catalogues for a universal item not aimed at us guys with more money than sense in the Scooby community. Look in the Burton Power catalogue or visit a motor sport orientated factor.
The pipe work is fidly. You need to relocate the breather from each cam cover and the rear crank case breather which incorpoates a one way pressure sensitive valve. All simple and straight forward bar the space to work in,where does that pipe lead to, (know what I mean?) but woth doing.
Will also reduce the possibility of det.

P20SPD

iTrader: (1)

I know what you mean about the pipes, thats what has put me off TBH. Its also put me off changing the inlet pipe, as i dont have the time to faff about if you know hat i mean.

Hopefully taking some time off work in abit, so will try and address it then, when i dont need the car. I will have a look in Demon tweeks as well, unless david can knock something up

For the not so technically minded, me, could you explain how it would reduce det?, although i hardly get any at the moment.

Cheers

Steven

harvey

iTrader: (48)

Of course I was forgetting that as "know the right people/man" then you could have the ultmate custom made item just for the hole you found to locate it in!!!
For my location see www.tyneteesscoobies.com. and ring me if you want more detail.

P20SPD

iTrader: (1)

Was looking on there the other day, and trying to remeber from Well Lane 3 and when we saw one another at the Shell Garage off the M1 near Wakefield.

Cheers

Steven