Ford Mondeo III (2000 - 2007) - 02 2.0 petrol erratic idle and stalling problems

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Sat 12 Jul 2008 17:47
02 2.0 petrol erratic idle and stalling problems - neilnev
Hi All,
I've got a 52 plate mondeo with a duratec 2.0 petrol engine that has just started idling erratically and stalling. Started suddenly the other day. Instead of idlling normally at about 900 rpm the revs oscillate. Sometimes they will oscillate by just 1 or 2 hundred revs about the normal idle speed, with an oscillation frequency of a couple of seconds but often the revs will drop very low and then oscillate between about 250 (nearly stalled) and about 750 rpm, oscillation frequency 2 or 3 seconds. The car struggles a bit to pull away and sometimes stalls but once it is moving and reving a bit higher it runs fine, no odd noises or vibration as far as I can see.
The problem started immediately after I'd accelerated the car hard from rest and rev'ed it to about 4500 or 5000 in first and second ....next time I came to idle the problem was there. it ws also a wet day but I didn't go through any big puddles. The engine was already warm from a 5 or 6 mile run and I don't think it is a damp electrical system....car has been in my garage for 3 days since so it should all be dry and the problem is still there.

So far I've checked the air filter (spotless) and the plugs (all fine, clean and gapped spot on) and checked the hoses on the air inlet and vacuum side of of the throttle body, all appear to be in place and I can't see or feel any splits where air could be getting in. Now wondering if it might be a partially blocked fuel filter, or trouble with the TPS (throttle position sensor) or idle control valve or....well I'm hjust guessing really :o(

Before I take the car to Ford for them to fix can anybody here help me please?

Many thanks,
Neil

Edited by neilnev on 12/07/2008 at 17:48

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Mon 14 Jul 2008 00:29
02 2.0 petrol erratic idle and stalling problems - MikeTorque
Possible throttle idle valve/sensor, should be easy to fix if that's the problem.
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Mon 14 Jul 2008 11:34
02 2.0 petrol erratic idle and stalling problems - Saltrampen
Check plugs are tight and leads are OK, then clean the Idle control valve if you know how.
This sometimes helps. If it was the coil pack, I guess it would miss at any revs.
If none of these help, then as you say look at Fuel filters (is the fuel pump noisey or struggling?). I guess you have the electronic EGR valve on this model and not the old vacuum system - check connector to EGR sensor is clean and secure.
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Mon 14 Jul 2008 14:27
02 2.0 petrol erratic idle and stalling problems - Screwloose
Neil

Might also be worth checking for an air leak into the inlet side. Split breather hoses are common - particularly under the coilpack.
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