choness2004

As above really, looking for a Subaru guru near Portsmouth that wouldn't mind looking at my car for me and helping work out what is exactly wrong with her.

Help would be appreciated, and beer money/man love can be provided!

quango2k

hi mate, whats up with the car?

only just see your post and I am in portchester.

choness2004

Hi gents, thanks for the replays. Well I'm sure it's my MAF, knock sensor and boost solenoid that's gone, so hopefully once they turn up my problems will be sorted.

It basically doesn't like idling and causes it to hunt, it's started cutting out when you start the car so I have to keep my foot on the throttle. And when warming up, it sounds like it's blowing air out of the induction pipe, but once warm this stops.

I would offer for you guys to have a look and drive her so you see what I mean, it's just all over the show really

Moley

iTrader: (9)

Subaru-4-u (Len)

quango2k

i have all of those sensors so I would be able to test but all of those would give you a cell code which I can also read and check all your fuel trims etc. if there is air coming out of the intake it sounds like a compression issue.

if you start the car and remove your oil cap and put your hand over it, not sealing it but very close..you should feel a pulsing air, both pushing and pulling..if any smoke comes out of there or purely blowing then there is a problem.

your boost solenoid wouldnt cause idle to hunt, your MAF might but you can just unplug it and you should be able to idle just fine. the knock sensor would throw a code.

choness2004

Ahh ok thanks, well I've got the knock sensor here and the other 2 on order.

I'll try the oil cap trick, I hadn't thought of that. I spoke to my college lecturer, who also thought it could be compression, but as soon as the car has warmed up it's stops which makes him think it isn't that.

I have my MAF unplugged at the minute, and idle just hunts when warm, but is awful when cold, so that could maybe be a temperature sensor?

quango2k

on the contrary, compression when the engine is cold the clearance between the pistons and sleeves will be greater..when warm this will close down and shrink.

with some engines you can hear piston slap when cold, more so with forged builds. this is down to the clearance between the pistons and sleeves.

as you think air is being forced out of the intake when cold this is telling me there is a compression issue, this is the only way this can happen as it is drawing air (sucking) through the pistons.

I can do a cold compression test for you if needed.

there is also a temp sensor in the manifold for coolant, this can cause idle to hunt like crazy. there are two right next to each other (i forget what they are called) it could be that but im more concerned about air coming out of the intake as that is far from normal.

choness2004

Ahh ok, well that's sounds like fun, I'm guessing it's a big job to set the clearances? How much would you want to do the tea for me?

Thanks for your help so far

sens3i

iTrader: (1)

Vacuum leak is also likely. Id advise changing as many vac lines as possible to you have access too as the old hartd plastic become tired and splits... the smallest of holes/cracks/splits can cause the car to hunt.....

quango2k

a vac leak would get worse when warm, not better as the plastics would expand not contract.

to the Op, its not a case of setting clearances..if your piston sleeves are worn, its engine out time for new pistons as a minimum.