Ford Focus - 05 MK2 focus idle problem - not the usual problem

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Tue 8 Sep 2015 23:09
Ford Focus - 05 MK2 focus idle problem - not the usual problem - Rabjam2003

Hi all,

I just bought a 2005 ford focus 1.6 petrol. the problem I have is as soon as i start the car it idle's at 1200 to 1300 rpm. once at full operating temp the car rev's up and down by itself and the trottle pedal doesnt work. I have changed the throttle body and air flow sensor, but no change.

I have also checked the rubber hose at the inlet manifold to see if there is a hole in it, but it is brand new. So someone has already changed this.

I also tried the reset procedure for the throttle body, disconect battery for 15 to 30 mins, start car to running temp without touching throttle pedal, then drive for 5 miles. still no change.

Can someone please help me ???

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Wed 9 Sep 2015 01:20
Ford Focus - 05 MK2 focus idle problem - not the usual problem - elekie&a/c doctor
Is the engine fault light on? Any fault codes logged in the engine control memory?
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Wed 9 Sep 2015 08:39
Ford Focus - 05 MK2 focus idle problem - not the usual problem - NARU

This sounds like it needs a methodical approach, checking for error codes, then checking that each sensor is operating correctly. This would include the temperature sensors, throttle position, etc.

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Thu 10 Sep 2015 16:19
Ford Focus - 05 MK2 focus idle problem - not the usual problem - Rabjam2003

Hi Marlot,

If one of the temp sensors was faulty, and the car thought it was cold outside all the time would that leave the revs high all the time ? Then when the car wamrs up the limp mode would would kick in ?

How many temp sensors are there on this car ?

Thanks

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Thu 10 Sep 2015 04:31
Ford Focus - 05 MK2 focus idle problem - not the usual problem - lawrence_ashby

Had this problem with a bmw, revs fluctuating and no throttle response turned out to be a failing crankshaft sensor, might be worth looking into.if you look into it theres two sensors, camshaft sensor and crankshaft sensor, it was that crank that caused my revs to fluctuate

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Thu 10 Sep 2015 15:04
Ford Focus - 05 MK2 focus idle problem - not the usual problem - Rabjam2003

Hi, No eml light on dash or codes logged.

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Thu 10 Sep 2015 15:08
Ford Focus - 05 MK2 focus idle problem - not the usual problem - Rabjam2003

Hi, were is the crank shaft sensor located ?

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