the latest on my irradic idle

[541NTT]

for anyone interested,

i thought my 04gt might have clogged an injector, like everyone elses seem to lol but i dropped it at the mechanic today and he has advised that what actually happenned is my timing is 10 degrees out, and it appears that this is due to my timing belt skipping a tooth.

so at this stage he says im at least up for a timing belt (so 20thou klms after it was replaced at max) and maybe a new tensioner, once he pulls it apart he will be able to tell.

he seems to think worse case a whole new timing belt/idle pullies and tensioner kit will be about the $800 mark.

[Ric]

Has he verified that it is missing a tooth, or just that it is a tooth out?
It ounds a lot like this problem, where the cams were just a tooth out...
http://forum.liberty.asn.au/viewtopic.php?p=47116#47116

[senator]

your lucky the belt has not snapped, but i think it might be more then just the belt, as ric said check the cams

[541NTT]

well he has verified it is a tooth out, but wel know more tommorrow as to why, im not sure if it is the same as that other post, ididnt read the whole thing but my car was at the point where it would stall under any kind of load, ie turning the steering wheel, applying the brakes(only at idle tho not when moving).

i hope this is the end of it and it will be fixed but who knows, he mentioned the vvt might be out as a result and will look at that to.

also an interesting fact, i asked if it could have done any damage internally and he advised that these engines are free running, so apparently the timing belt can completely snap and the car will just stall with not damage to the valves or whathave you.

[smythie]

that is a very optimistic POV there. If there is anything driving the crank (ie running down the road) the pistons will still continue to go back and forth while the valves (with some potentially sticking out into the combustion chamber) will stop . They won't collapse either as the camshaft will hold them open. At least that is the way I see it

[Ric]

I guess by "free running", the mechanic means that the valves cannot touch the pistons when they are fully extended.
Some engines do, and some don't. I don't personally know if Subaru engines do. I've certainly seen what happened to a Daihatsu engine when the timing belt lost a few teeth, enough bent valves that it was cheaper to get a complete replacement head.

(1.0 litre, 3 cylinder, turbo-charged Charade. Was a great car to drive )

[smythie]

ahh, ok after some basic calculations (assuming flat piston and combustion chamber) I get the following squish height figures for our Libs

2.5GT:- 10.7mm
2.5i:- 8.8mm
3.0:- 8.25mm
2.0GT:- 8.8mm (couldn't find the bore/stroke dimensions so assumed from the current Impreza)

I guess, provided the valve lift is no more than 7 or 8mm your GT would be fine (conservative)

[541NTT]

update:

went and sore my mechanic yesterday, apparently its the hydraulic device behind the timing belt tensioner, he says that it doesnt keep a constant pressure against the timing belt and although it is tight when the car is switched off, it slackens off over time (the timing belt had about an inch of play withing 12 hours) so this is what has caused the timing belt to jump a tooth, he also says that the timing belt looks like it hadnt been changed at my 100thou service, this annoys me but i didnt own the car when it was done (tho the log book is marked off) so i cant really proove it.

he also says that cylinder 3 was intermitedly cutting out, and when he looked closer into it the coil was dead, he says that it traced up to the cover and arked out causing the coil to become faulty. ive seen this happen when i was completing me apprentice ship, its like anything with an exposed current can create a little vien of microscopic conductive shavings and this can cause issues.

so provided this coil comes in today i should have my car back this afternoon.. if nothing else pops up..

[moggy]

At least you'll know your timing belt has definitely been changed now!

Bob.

[541NTT]

At least you'll know your timing belt has definitely been changed now!

Bob.

haha yeah ahmen.

[541NTT]

well my mechanic returned the car to me today, in exactly the same state as it was, he appologised emensley and said he could not figure out what the deal is, hes only charging me for the timing belt and service but was really stumped.

i dont know how this worked but i have now booked the car in with Boxer Service up on the northside of bris, they specialise in the engine and ive described everything so far and they seemed a bit baffled, so they have the car next week and i am hoping they get onto something

[CheesyMong]

update:

went and sore my mechanic yesterday, apparently its the hydraulic device behind the timing belt tensioner, he says that it doesnt keep a constant pressure against the timing belt and although it is tight when the car is switched off, it slackens off over time (the timing belt had about an inch of play withing 12 hours) so this is what has caused the timing belt to jump a tooth, he also says that the timing belt looks like it hadnt been changed at my 100thou service, this annoys me but i didnt own the car when it was done (tho the log book is marked off) so i cant really proove it.

he also says that cylinder 3 was intermitedly cutting out, and when he looked closer into it the coil was dead, he says that it traced up to the cover and arked out causing the coil to become faulty. ive seen this happen when i was completing me apprentice ship, its like anything with an exposed current can create a little vien of microscopic conductive shavings and this can cause issues.

so provided this coil comes in today i should have my car back this afternoon.. if nothing else pops up..

What happened to this diagnosis or was he pulling that out of thin air lol

[541NTT]

update:

went and sore my mechanic yesterday, apparently its the hydraulic device behind the timing belt tensioner, he says that it doesnt keep a constant pressure against the timing belt and although it is tight when the car is switched off, it slackens off over time (the timing belt had about an inch of play withing 12 hours) so this is what has caused the timing belt to jump a tooth, he also says that the timing belt looks like it hadnt been changed at my 100thou service, this annoys me but i didnt own the car when it was done (tho the log book is marked off) so i cant really proove it.

he also says that cylinder 3 was intermitedly cutting out, and when he looked closer into it the coil was dead, he says that it traced up to the cover and arked out causing the coil to become faulty. ive seen this happen when i was completing me apprentice ship, its like anything with an exposed current can create a little vien of microscopic conductive shavings and this can cause issues.

so provided this coil comes in today i should have my car back this afternoon.. if nothing else pops up..

What happened to this diagnosis or was he pulling that out of thin air lol

i have no idea, he replaced the coil, problem was still there, the car runs probably a little smoother than it was but still has the issue.

[CheesyMong]

update:

went and sore my mechanic yesterday, apparently its the hydraulic device behind the timing belt tensioner, he says that it doesnt keep a constant pressure against the timing belt and although it is tight when the car is switched off, it slackens off over time (the timing belt had about an inch of play withing 12 hours) so this is what has caused the timing belt to jump a tooth, he also says that the timing belt looks like it hadnt been changed at my 100thou service, this annoys me but i didnt own the car when it was done (tho the log book is marked off) so i cant really proove it.

he also says that cylinder 3 was intermitedly cutting out, and when he looked closer into it the coil was dead, he says that it traced up to the cover and arked out causing the coil to become faulty. ive seen this happen when i was completing me apprentice ship, its like anything with an exposed current can create a little vien of microscopic conductive shavings and this can cause issues.

so provided this coil comes in today i should have my car back this afternoon.. if nothing else pops up..

What happened to this diagnosis or was he pulling that out of thin air lol

i have no idea, he replaced the coil, problem was still there, the car runs probably a little smoother than it was but still has the issue.

However I am impressed he only charged you for the timing belt work that does show good ethics...

[cbforensics]

Yeh......

I'm no mechanic but it does sound like a load problem to me - moving the steering wheel to make the engine stall at idle is strange.

From a simple perspective, it's a case that the engine is under load when the power steering is applied. The power steering uses power that is indirectly fed from the belts, which may cause sufficient load on the camshafts to slow down the revs to a point that she stalls.

Is it a fuel/oxygen mix problem??? Is the incorrect fuel mix getting to the chambers? Or is it in any way possible that it is a bad fuel you have onboard???

In my old days of mucking around with carbies and adjusting air/fuel mixtures, I did find that if the mix was light she did tend to stall under load at idle.

Good luck with finding the answer!!!