Uneven Idle

**gjb71** · Wednesday 3rd May 2006, 16:27

Can anyone help out, i've got a 2001 v70 t5 unmodded 85k on clock, its started to rev unevenly. only seems to do it on idle sits at around 700rpm then drops to 600 and bounces back up to 800, does it a couple of times before settling back at 700.
Have noticed that if i turn the air con off it seems to sort its self out and if stood outside you can hear a click from engine bay before revs go off on one.
Codes have been checked and theres nowt showing up.

cheers g

**JUDGENINJA** · Wednesday 3rd May 2006, 16:36

Is the the rubber elbow arising again. ????

As your facing the engine look to the left of the inlet manifold for a rubber elbow (if fitted to your car). It's a common thing to break down over time...

**Vikingxl** · Wednesday 3rd May 2006, 16:46

Could be the dreaded etm

**JUDGENINJA** · Wednesday 3rd May 2006, 16:57

oh yeah...it's one of those cars.....

**gjb71** · Wednesday 3rd May 2006, 20:45

Originally Posted by JUDGENINJA

oh yeah...it's one of those cars.....

what do u mean its one of those cars, pls tell me i'm frightened now

**JUDGENINJA** · Thursday 4th May 2006, 14:55

Don't worry too much... the ETM is a common fault that is particular to V70's. Volvo reckoned 80% will fail at some point.

Because mine is an 850 I have a normal cable, so you've "got one of those cars"......sorry I didn't want to worry you too much.....

**gjb71** · Thursday 4th May 2006, 22:51

damn those so called advances in technology, ah well i can live with it for the time being, runs fine other than that.

**kasi232** · Thursday 4th May 2006, 23:13

Hi I had the same problem with my v70 t5 when I got it.So I took it to volvo for diagnostics, it turned out to be the fuel ecu cost me £475 for a new one runs fine now

**rgracin** · Friday 5th May 2006, 10:09

Sounds like the ETM. I have '01 T5 as well. I took my ETM off myself, cleaned the gunk out, put it back on, and it has been perfect since. If you leave it, it just get's worst, and you can start to feel it getting erratic through the rev range.

The butterfly in the throttle body is angled slightly at idle, and the gunk narrows the gap so the engine can't idle properly, the 'brain' squirts more fuel in to stop it stalling, then leaves it to idle and it all happens again, hence the hunting revs.

Do it yourself if you can. It's a little fiddly, but cheaper than getting a garage to do it, and far more satisfying.

**Wobbly Dave** · Friday 5th May 2006, 10:23

You're all taking rubbish!! Stop scaring the man!!

If indeed the problem goes away when you disengage the A/C then that's perfectly normal. The clicking is the clutch on the A/C pump - also very normal. ETM failure - the idle is all over the shop very pronounced - not just +/- 100 rpm!!

YOU DONT HAVE A FAILED ETM - COZ YOU GOT NO CODES!!!!

What you do have is the air conditioning on. Which is a nice thing!!

Look at my answers on here...
http://www.vpcuk.org/forums/t10027-a...question-.html

To check a ETM you need to turn the A/c off - rev the engine - and watch the counter fall - it should return smoothly and slow for the last 200 rpm.

**gjb71** · Friday 12th May 2006, 10:25

thanks for all the above, dave i tried turning the a/c off and revin it. it does exactly as u said slows for the last few hundred before returning to norm, this thing mithered me though coz i now had the silver landshark for around 18 months nad this has only just started, before this it was steady as a rock

**SaffronC70** · Friday 12th May 2006, 12:11

Hi

I have "one of those cars", lol !

Mine does the same thing occasionally, dropping to 600 and back up etc, sometimes +/- 100rpm at idle and sometimes when the aircon cuts on/off.

VT told me to get an ETM, I did and it was the same ! The car has had two more ETMs since then and the idle is still the same, lol.

Most days it is fine though . . . still looking for the answer.

Chris

**roadrunner** · Saturday 10th June 2006, 10:01

Hi i to have one of those cars and mine has an uneven idle, thought i might have a go at cleaning the etm but can anyone point me in the right direction as to where it is under the bonnet. 2001 v70t5 ex plod. (yes i know i shouldn`t have but it was very cheap).

cheers

roadrunner

**Frisbee78** · Saturday 10th June 2006, 11:35

Hi all

I have the same problem with my V70 T5 (99) but only when the engine is warm. Sometimes (rarely) it will idle steadly for 5 secs at 900 rpm but then it will start bouncing up and down between 800 and 1000 rpm again. It does it regardless of the aircon setting.

My wife's 850 had the same problem a few years ago but I'm not sure what was done to solve the problem back then. The fuel systems of the 2 cars are probably different anyway.

Just a thought: is the ETM controled by the ECU? If so, would an ECU upgrade solve the problem? If so, how much would Volvo take for doing this? Maybe a RICA upgrade while we're at it?

Also, when you say to clean the ETM, do you mean clean the pipe and butterfly (the mechanics)?

Seb

**SaffronC70** · Saturday 10th June 2006, 11:46

I have solved this problem - it is the non-return valve between the EVAP valve and the intake piping before the turbo.

As this fails open it creates an air leak affecting idle quality.

The valve is located on the piping on the side of the engine block on the air box side - small grey valve and can be pulled apart without tools to be checked.

I added another valve in line instead of replacing the failed one, as Volvo want £48 for the valve including new piping unfortunetly.

Hope this helps !

Chris

**Frisbee78** · Sunday 11th June 2006, 18:06

Thanks for your reply.

How did you go about testing the non-return valve?

As I don't have a Haynes manual yet, can you confirm I identified the valve correctly? (see pics)

Thanks for your help.

Seb

**SaffronC70** · Sunday 11th June 2006, 18:24

Hi there

Image 28 is your boost control solenoid (BCS)
Image 29 is the EVAP valve ! 10 points there !

Attached pic is of the extra valve I have put inline in the (middle of the pic), just before that is the non-return valve.

To test - suck it and see ! should only allow you to suck and not blow.

Easiest to pull it off at the turbo end and suck there, lol.

Chris

**Frisbee78** · Sunday 11th June 2006, 18:35

Cool! Thanks. Now I know what to look for

New car, new things to learn...

**Frisbee78** · Monday 12th June 2006, 19:12

Well, I checked the non-return valve and it works as it should.

So back to square one...

**Frisbee78** · Saturday 17th June 2006, 18:19

Hi all

I just found out that there is another non return valve on the EVAP line between the T union and the intake manifold and mine's dead.
Chris, where did you get your replacement? The £45 price tag from Volvo doesn't really suit...

Another thing: is there an idle control valve on a ME7 turbo engine? I think the ETM makes it redundant, but want to check.

Seb