2004 GT, very low idle.

[bennyh]

Hi all, been lurking for a while, unfortunately this is my first post!

I picked up a MY04 lib gt wagon a few months ago and I've loved it since. It's a great car.

In the past few weeks though, the idle has dropped to about 300-400rpms when in drive or reverse. Reverse seems worse than drive, and neutral seems better than either.

I've searched a lot, and seen quite a few different suggestions, including:

Variable valve timing solenoid filter / banjo bolt thingy.
Turbo dying
Bad oil
Bad fuel
Vacuum leak

I've got it booked in for an inspection with subaru north shore (Sydney) on Friday, for an inspection, but wondered if anyone had any suggestions for things I can try myself or specifically ask them to check.

There are no other symptoms, power seems normal throughout the rev range. The engine is completely stock other than a gfb bov that was on the car when I bought it. Forgot to mention, it at 130,000kms.
Also, will this be doing any damage to the engine? Aka, should I hold off from driving it until they inspect?

Lastly, If anyone has one of the diagnostic reader cables in Sydney, that I could come and use for a few minutes, I'm happy to give you a few $$ / beer as thanks.

Cheers,
Ben

[kiahatsiu]

Is the idle still smooth? If it is kinda erratic you might have an air leak.
Is your blow off valve plumbed back? If it is an atmo one it might be your car trying to tell you it is a shit idea and it doesn't like looking like a teenager's car.
When was it last serviced? Could be any combination of things, dirty AFM wires or something.
It won't be the turbo; unless the turbo is completely seized, but I think you would have other complaints if that were true.

Service is the best bet. See if you can find a subaru specialist, rather than taking it to a subaru dealership. You would be amazed how little they know.

[bennyh]

Cheers for the reply, answers and a few things I forgot to mention..

The idle at first start is about 1500, and is fine hovering around 900ish until warm, then it drops.
It is not smooth, it feels like it is a bit shaky and it hunts from 200-600rpm, usually settling around 3-400 but still bounces around between those ranges. It's different at every set of lights to be honest -_-

It is an adjustable one, its set to about 75% recirc, 25% atmo, but it was on since I bought the car and didn't have any problems for 2 months, so I don't think it's the bov. I've tried 100% recirc and it didn't fix anything. One thing though, the vacuum hose from the bov does not have a clamp on it, but sits tight and seems to be airtight.

Any suggestions on attempting to clean the afm/afm wires? Or best avoided for a semi-noob?

Any suggestions on subaru specialists? I'm usually living between neutral bay and newtown, so anywhere around the north shore or inner west would be ideal. Interesting about the dealership comment... but to an extent it doesn't surprise me. They've offered me an engine inspection for $60 with no obligation to proceed with them, so might be cheaper than a garage? Though they probs won't do much else expect plug a computer in and have a look at the stats..

So again, if anyone has a computer link up cable in the Sydney area.. Hit us up!

[kiahatsiu]

I am in Brisbane so sorry I cannot advise on specialists in Syd.
Do you get any check engine lights (CEL) at all? I had a leak on my boost control solenoid which resulted in an errattic idle which was 400 odd to 1200, but it through up a CEL. Also, it would only happend in I provoked it by "blipping" the throttle.
Try running around with the BOV 100% recirculated. Do it for a few days. Is the reference line to the BOV in good nick?

[bennyh]

New weirdness with it tonight...

Drove about 20kms, it idled well. Smooth and around 800, which I'm assuming is near normal?
Didnt drive for anout 3 hours, car was cold again and then drove most of the way home, it idled perfectly again..
Until, I went into tiptronic and was boosting around a bit, then the revs started to drop to the 4-500 mark when idling..

So for the time with no issues I was in drive and off boost / granny driving nearly all of the trip, but after having a bit of a squirt in tiptronic (which I normally do..) that's when the issues arose..

Are there any obvious things this would cause this behavior?

Also, before this I hadn't driven for over 2 days, I normally drive 3-4 times a day.. Maybe my car just needs as much sleep as I do?

Confused...

Edit: in reply to the above, no CEL ever. I'll set the bov to recirc until Friday, see how it goes and report back.
Both bov lines seem in good nick with good tight connections.

[skubesnaps]

I had a similar problem with mine... took it to a Subaru mechanic who had the car for three weeks and couldn't fix it. Long story short; I took it to Subaru and they sorted it out in a couple of hours... turned out to be a variable valve timing - filter issue.
I suggest you take it to Subaru... seems to be a common problem, I;m sure they'll sort you out...