idle hunting on my T5

[Mark V70 T5]

when sat at a junction and in neutral the idle jumps from about 600-900 rpm and then will settle down after about 6 jumps.............. when going along if im going down hill and i put it into neurtal then its jumping from 600-1500 all the time ! its not a problem but sometimes in traffic its making take off jolty (auto box) !!

WHY please??

if i can find out what it is...... il visit a scrappy for the replacement part!

also it may be linked but the fault light is on and its been coded as a vacuum problem!! but iv checked under the bonnet and cant see anything apparently wrong..........

[volvo]

Have you checked for an air leak? The vac pipes sometimes have a crack in them that can cause it to 'hunt'?

Once they have been checked and no issue found, you can try to clean out the idle control valve, its pretty straight forward, and thats something, coming from me!

i doubt it will be the autobox, hope not......

good luck!

[sporty tinkhams bear]

erm my other non turbo 1997 v70 has been doing this, and I'm not shure what it is. Someone said it could be the fuel pump, is yours worse when the tank is emty mine is really bad when cold and is takeing ages to get to the normal running temp. I have cleaed the maf and Idle valve but this has not improved it at all, I am now going to look at all the vac pipes as its cheeper than a new pump

[volvo]

i heard its not good practice to let your fuel go 'so low' to a point that the tank is empty or nearly there....the reason being all the 'crap' over time, gathers at the bottom of that tank and when the fuel at the bottom is used and feeds through the injectors, you are not using 'clean' fuel, which can cause the injectors to clogg up. If this is the case, then the fuel pump may well need replacing first but i would try the other steps first as they are cheaper!

[SteveRuss]

when sat at a junction and in neutral the idle jumps from about 600-900 rpm and then will settle down after about 6 jumps.............. when going along if im going down hill and i put it into neurtal then its jumping from 600-1500 all the time ! its not a problem but sometimes in traffic its making take off jolty (auto box) !!

WHY please??

if i can find out what it is...... il visit a scrappy for the replacement part!

also it may be linked but the fault light is on and its been coded as a vacuum problem!! but iv checked under the bonnet and cant see anything apparently wrong..........

Common fault with the fly by wire ETM. I don't know if yours has one though.. If it has, then there is a high chance this is the problem.

http://www.volvoclub.org.uk/etm.shtml

[ame="http://www.youtube.com/watch?v=LfG1_QKYu_E"]http://www.youtube.com/watch?v=LfG1_QKYu_E[/ame]

I had that exact issue with my C70 T5, 1999 (what year is yours?) which was resolved with a replacement. If you read up on cleaning it, then it didn't work on mine, for what it's worth. The solution is a replacement.

The engine would hunt all the time. Stalled a few times as it got worse. Sometimes it was fine then it would hunt between just above stalling to around 1500rpm. Really frickin' annoying..

If it is the ETM, then they are pretty expensive although Volvo admitted there was an issue and were selling them for £150 each +. I had my new one fitted for £50 odd and the problem was solved. I doubt they are still offering them at what is probably their cost. In fact, I think they whacked the price back up again so it's an expensive fix sadly. I believe however that you can fit from one car to the other so a breakers might be the cheapest ETM fix (if indeed that is your problem).

I recommend you research this issue as it's pretty massive..

Regards. Steve

[M-R-P]

If your inlet manifold looks like mine...(sorry, bad pic)

You could still have the Magnetti Marelli throttle unit which were well known for this problem. Volvo were replacing them for free up till a few years ago.

[SteveRuss]

If your inlet manifold looks like mine...(sorry, bad pic)

You could still have the Magnetti Marelli throttle unit which were well known for this problem. Volvo were replacing them for free up till a few years ago.

They weren't replacing them for free in the Uk two years ago. In fact, they agreed that they would drop the price to £140-150 plus vat instead of £450 odd'. You then needed to put software on them (£1 plus a silly upload fee which was £40 or so..). They would then try and have a load more for fitting them. I can't remember what they quoted me but I think it was an hour and a half. My local Volvo garage fitted it in around 15 mins from start to finish (1999 C70 T5 which is apparently easier than some..)

I hummed and harr'd whether to buy another Volvo after my C70 blew up and to be honest, the way Volvo have treated people (mainly outside of the US and Australia) with regard to this shoddy part, kind of put me off them altogether. I know all the other automotive manufacturers in the world are pretty much of the same opinion where they turn their backs on customers woes in favour of making more cash out of them. But, something about Volvo's ETM issue left me really sour at the company, even now.

Their 'putting the price back up' to replace the Magneti Marelli junk they originally put in their cars should be the last straw for anyone that has lived through the issue. I've no trust left in their cars at the moment so I went back to Audi recently. My last Volvo had two ETM's fitted over it's life and two cleaning sessions. Well over a thousand pounds made for a poor design.

Lets hope the OP doesn't have this issue and if he does, he manages to find a used module to replace it with at a reasonable cost. I scrapped my C70 a few weeks ago and didn't remove the ETM. I would have almost be willing to give it to someone to balance the misery this has caused so many people.

Rant over..

Regards. Steve

[M-R-P]

I sit corrected, The plod changed mine before I got it and had read somewhere it was a free fix due to the alarming regularity of the failure. I know where you're coming from regarding Volvo's lack of interest in faulty parts - I just had my DIM replaced - £735. Renault had a similar problem with their dims and charged £100 to fix the problem, taking a hit of hundreds of pounds for the sake of not getting a bad reputation. I did get an ECU update thrown in for nowt tho.

[Mark V70 T5]

If your inlet manifold looks like mine...(sorry, bad pic)

You could still have the Magnetti Marelli throttle unit which were well known for this problem. Volvo were replacing them for free up till a few years ago.

yeah under the bonnet does look like that actually!! where is the part i need to replace? the throttle body or the ETM ? il visit a scrappy!!

[M-R-P]

Ok, it's smack in the middle of the inlet manifold - underneath with a charge air tube attached to it. There's a black box about the size of a pack of fags.
Bad news is... I think (prepared to be corrected) they are coded to the car i.e. swap it with a scrappy one and the all-knowing ME7 management system will throw a wobbly and the car probably won't start .
Aparantly, they can be disassembled, cleaned and rebuilt but it's something I haven't tried (but will probably have to, soon).

[si850r]

like said previously, check air lines and clean your control valve...Mine did the same as yours and i replaced all the vac lines with braided fuel hose ( off flea bay) and took off the idle valve and gave it a damn good clean with carb cleaner ( the valve should rattle when cleaned properly). This sorted the trick for me.....

[Mark V70 T5]

like said previously, check air lines and clean your control valve...Mine did the same as yours and i replaced all the vac lines with braided fuel hose ( off flea bay) and took off the idle valve and gave it a damn good clean with carb cleaner ( the valve should rattle when cleaned properly). This sorted the trick for me.....

where is this valve? is it the one on the side of the airbox? with pipes either side?

[M-R-P]

I thought the ME7 with electronic throttle module didn't have an idle control valve?
the one on the airbox is the boost control solenoid.

P1 mani with idle control valve, I think it's on the right hand side somewhere...

P2 mani with that tricky throttle module...

If yours looks like the top one then the idol control valve needs cleaning, If it looks like the bottom one, then ecm needs cleaning.
I'm happy to be correct but I'm sure the ME7 doesn't have an idle control valve.

[LeeT5]

i heard its not good practice to let your fuel go 'so low' to a point that the tank is empty or nearly there....the reason being all the 'crap' over time, gathers at the bottom of that tank and when the fuel at the bottom is used and feeds through the injectors, you are not using 'clean' fuel, which can cause the injectors to clogg up. If this is the case, then the fuel pump may well need replacing first but i would try the other steps first as they are cheaper!

Hate to say it but that is a myth nowadays!

Back in the day when fuel tanks were made of metal and would corrode, Yes, but not now fuel tanks are made of plastic. Also, fuel is so highly refined and fuel filter technology vastly improved. It won't make a jolt of difference if you run you tank low...just means the car will cut out at the next steep hill!

Best practise is to not go less than quarter of a tank.

[Mark V70 T5]

im getting confused!! i bought some carb cleaner the weekend ! what and where am i cleaning with it? i think its the bottom one ....... il have a look in a bit

[shyfx003]

Sorry to jump in half way through this thread..when i bought my t5 a few months ago,it too would start hunting when sat at lights or like you say going down a hill in neautral..i too was baffled by science..i have little patience so fired the car to an idependent volvo garage..to be told its fine and yes its just passed its mot..wtf? it was running like a bag *%"t..one thread that i did come accross was about the crankcase breather..when the car is doing its thing at idle,pull the dipstick out and see if its venting..it that is the case u know where to start..if not then follow on what some of the others have already stated..

[pigfight]

2 things which havent been mentioned yet which could be the culprits:

1: fuel filter needs replacing, cheap and easy.

2: get a compression test done, if one of the cylinders are out, then this is the root of your problem.

fingers crossed that its something simple like the filter or air leak.

[SteveRuss]

Bad news is... I think (prepared to be corrected) they are coded to the car i.e. swap it with a scrappy one and the all-knowing ME7 management system will throw a wobbly and the car probably won't start .

I have heard of people swapping ETM's on the T5's with no issues. It was a few years ago that I was dealing with it though so I don't remember the details.

I bought new and had it flashed with the software at an independent garage in Bristol. Maybe if you flash it with the software it will accept the ETM, if indeed there are any issues with it being accepted in to a different car.

I've mentioned before that cleaning the ETM in my case didn't work. It was something the garage offered to do for an hours labour and if it didn't work, they would take that off the labour charge for replacing the unit with a new one. Pretty reasonable really (Elite Volvo, Bristol). As far as I remember, it's the metal strips/brush that wear on the board that creates the problem. Again, I can't remember the exact details other than it was a crap design and Volvo have decided to make as much money out of it as possible.

Look for a replacement with a yellow sticker. My new yellow sticker'd ETM lasted for around three years with no issues and went with the car when it blew up, still working fine..

Regards. Steve