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Engine revving when idle... (Mk3 Mondeo)

Discussion in 'Motors' started by Pookie Bear, Nov 25, 2010.

  1. Pookie Bear

    Mobster

    Joined: Jun 28, 2006

    Posts: 4,796

    Location: Newcastle upon Tyne

    Just noticed this issue two nights ago on the way home and wondered if if it's something I should get looked at.

    I drive a Mk3 Mondeo, 2004, Petrol 1.8 with 60k on the clock. After changing gear, my rev counter will sit at 1.5k revs, sometimes 2k revs, before settling down to the normal idle (just under 1k) after a couple seconds. So when I pull up to a pedestrian crossing, I put the car in first and keep the clutch in, the engine revs up (scared an old lady this afternoon!), but it also happens when I put the car in neutral. Even when I'm tootling along and changing up or down, it will head for 1.5 or 2 when I push the clutch in, rather than 1k like normal.

    A week ago my clutch started squeaking intermittently. Related, or just a coincidental squeaky pedal?

    I'm fairly inept when it comes to cars (I can change tyres and fluids - I'm ok with DIY, just never done much with my cars) so curious as to whether it's something I can take a look at, or should I take it along to the local mechanic (in which case having an idea what the problem is might help me not get ripped off)?

    Thanks for any advice you can offer.
     
  2. oO Stevie Oo

    Hitman

    Joined: Nov 6, 2010

    Posts: 889

    Location: Behind the camera...

    clean out the IAC (idle air control valve) should sort your idling issue
    cant see it being an air leak after MAF cos your revs a settling again
     
  3. Peerzy

    Soldato

    Joined: Nov 9, 2008

    Posts: 6,424

    Idle Control Valve (ICV) I would have though, give it a good clean and see if that helps.
     
  4. EliotG

    Wise Guy

    Joined: Sep 20, 2006

    Posts: 2,297

    Location: Farnborough

    Throttle body clean?
     
  5. Pookie Bear

    Mobster

    Joined: Jun 28, 2006

    Posts: 4,796

    Location: Newcastle upon Tyne

    Right, I'll have a Google on that valve and see how easy it is to clean it out.

    Thanks for the advice.
     
  6. Pookie Bear

    Mobster

    Joined: Jun 28, 2006

    Posts: 4,796

    Location: Newcastle upon Tyne

    Ok, so I took the valve off, cleaned it out and will be going for a test run shortly (didn't see much gunk coming out - ran clear almost immediately). Should I have also cleaned the non-removable part, or just the part I actually took off?
     
    Last edited: Dec 4, 2010
  7. LEK-89

    Wise Guy

    Joined: Oct 11, 2008

    Posts: 1,859

    Location: Leicestershire

    Sounds like to me that the Throttle Position Sensor may need replacing (That's if they have them on MK3 Mondeo's), I had the same problem with my 1.25 Zetec Fiesta where the revs would stick at the same place for around 4 seconds before dropping down to just under 1000rpm's. These are a common thing to play up on the Zetec engines and the only fix is to replace this sensor. They are usually only £30 from local motor factors or a well known auction site.

    The ICV is also a possiblity as mentioned but the ICV's job is to regulate and control the air only when the car is idle.

    Liam
     
    Last edited: Dec 4, 2010
  8. Pookie Bear

    Mobster

    Joined: Jun 28, 2006

    Posts: 4,796

    Location: Newcastle upon Tyne

    Well, cleaning the part I removed (as per previous post) was not successful - went for a short test run and the problem persisted.

    Is it possible I've just been over optimistic and I should wait a day or two, or should I clean the part of the valve I don't remove, or is this a job for the local mechanics?
     
  9. LEK-89

    Wise Guy

    Joined: Oct 11, 2008

    Posts: 1,859

    Location: Leicestershire

    I would look into to see if your Mondeo has a Throttle Position Sensor and try and test another one from another Mondeo to see if it cures the problem first. The cleaning of the ICV obviously sounds like it has not cured the problem as if the ICV was the cause, you would of noticed a change after cleaning it straight away.

    Liam
     
  10. Stumble Bum

    Wise Guy

    Joined: Apr 2, 2009

    Posts: 1,624

    Location: Location, Location!

    disconnect the throttle position sensor. The ecu should then operate without the sensor, and operate on default idle settings. If you're still getting throttle problems then it's not the throttle position sensor. If the problem goes away then it would suggest a faulty throttle position sensor and should probably be replaced.

    This may or may not be correct.
     
  11. LEK-89

    Wise Guy

    Joined: Oct 11, 2008

    Posts: 1,859

    Location: Leicestershire

    From what I have previously discovered the car will stall within 5 minutes or the car will try to stall with the Throttle Position Sensor disconnected. The best way to eliminate the Throttle Position Sensor is to try a another one.

    Liam
     
  12. iaind

    Capodecina

    Joined: Feb 26, 2009

    Posts: 14,738

    Location: Exeter

    Fly by wire throttle on these iirc
     
  13. Pookie Bear

    Mobster

    Joined: Jun 28, 2006

    Posts: 4,796

    Location: Newcastle upon Tyne

    Thanks fellas. I guess I'll try cleaning out the main part tomorrow when I have some daylight and if that fails, I'll take it to the guy down the road for an assessment. I could "borrow" my brother's valve but I'm not sure he'd want me digging around in his engine, seeing as I normally don't do anything beyond filling wiper fluid and putting petrol in :D
     
  14. Pookie Bear

    Mobster

    Joined: Jun 28, 2006

    Posts: 4,796

    Location: Newcastle upon Tyne

    Well, I gave it some settling in time, but the problem persists. It doesn't really start until five minutes or so into my trip, so it waits for the engine to warm up before it starts giving me problems. Good news for short trips, not so goodnews for anything more than a few miles! I've given up with my feeble attempts to resolve it, so off to the local garage it goes.

    Thanks to everyone who commented - I feel like I've improved my knowledge of cars by about 100% just from removing my IACV and cleaning it out :D
     
  15. c180

    Associate

    Joined: Jul 21, 2011

    Posts: 3

    Location: East Midlands

    Hi Pookie Bear,
    Did you get the car fixed if so what was the cause of the problem? I am going through the same thing with my 2004 2ltr petrol Mondeo, I have just replaced the idle air control valve and still have the same problem as you had, any info would be gratefully received.
     
  16. Pookie Bear

    Mobster

    Joined: Jun 28, 2006

    Posts: 4,796

    Location: Newcastle upon Tyne

    It turned out that there was a split air-pipe under my engine (S-shaped) and it was only getting worse. Sadly, they had to lift the engine out to replace it (so the labour costs were ten times the cost of the part), but the problem disappeared after they did the work.

    Hope that helps.
     
  17. The Running Man

    Caporegime

    Joined: Oct 18, 2002

    Posts: 31,708

    Location: block 16, cell 12

    Holy carp they had to lift the engine to replace an airpipe?

    Have they not heard of gaffa tape?
     
  18. c180

    Associate

    Joined: Jul 21, 2011

    Posts: 3

    Location: East Midlands

    Many thanks, that will be my next stop then, will have a go my self, not sure how far i will get, can't even see it from up top. glad the problem disappeared after they did the work. :)
     
  19. c180

    Associate

    Joined: Jul 21, 2011

    Posts: 3

    Location: East Midlands

    Job done!!

    Three hours work not easy but no problems, found a split two inches long in a six inch pipe, twenty six pounds from the local Ford dealership. The car is now working as it should.
    Many thanks.:)
     
  20. geezer14529

    Associate

    Joined: Mar 24, 2012

    Posts: 2

    Revving Mondeo

    I have exactly the same issue. Today I replaced the idle control valve after my local garage ran diagnostics and said it is definately that. Still no joy and I am pretty sure it would be an air leak somewhere. Just after some information on this pipe you channged in the engine, as in where it is located and how to get to it to change it. Any information greatly appreciated I really need to get this fixed.
     


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