Engine revving when idle... (Mk3 Mondeo)

Pookie Bear · 25 Nov 2010 at 14:57

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.

Pookie Bear · 25 Nov 2010 at 15:53

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

Thanks for the advice.

Pookie Bear · 4 Dec 2010 at 13:06

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?

Pookie Bear · 4 Dec 2010 at 15:24

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?

Pookie Bear · 4 Dec 2010 at 19:41

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

Pookie Bear · 6 Dec 2010 at 11:15

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

Pookie Bear · 25 Jul 2011 at 12:00

c180 said:
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.

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.