ford mondeo mk2 1800 - mondeo idle/emissions & brake pedal travel problem

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Fri 11 Mar 2011 20:18
ford mondeo mk2 1800 - mondeo idle/emissions & brake pedal travel problem - daniel79

hi,

my wife's mondeo has just failed it mot on two things;

1) brake pedal travel too far - the brakes work fine, but the travel is a bit further than it should be, on the first mot this was only and advisory, but on the re-test i got a different chap who refused to re-test it saying it was dangerous......

I have changed the front discs and pads, one real wheel cylinder as it had seized, then the pedal travel problem appeared. I have bled the system several times, but the problem remains - any ideas??

2) emissions too high - CO was 0.40 on first fast idle test when it should have been 0.30? but more annoyingly the natural idle test was aborted as the idle speed is too high, now this one confuses me - the car starts and idles at 1500 from cold, then drops to about 950 after a few minutes, when the car reaches normal temp (i can't tell when this is as the temp gauge doesn't work!) but after driving for about 5 mins, the idle speed goes back up to 1200-1500.

i've rea that this could be the cat or lambda sensor, or maf, or ecu temp sender or anything really, but don't want to be changing everything just to see - what could be the most likely?

any suggestions are most welcome, as i'm out of ideas!!

many thanks

dan

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Sun 13 Mar 2011 15:14
ford mondeo mk2 1800 - mondeo idle/emissions & brake pedal travel problem - injection doc

I'm sorry but I have to ask, are the pads and Discs new or s/hand ? seen it so many times before ! If they are s/hand they will take ages to bed in and you will have a really soft pedal.

Have the rear brakes been adjusted up correctly ? yes you can overide auto adjustment and are the rear drums worn? may be if you clamp the raer hoses and see if the pedal is hard you know the problem is with the rears ! Have the brakes been pressure bled ? only way to really do it !

Emissions, I would suggest a live data check with a diag tool. May be a coolant sensor issue giving the wrong live data to the ecu. Make sure there are no vacum leaks around the inlet as these will increase idle speed cold and hot and cause higher co . They are prone to cats but all other avenues must be explored first. I have known a vacum leak on a heater control valve to cause the emissions to fails due to the lambda trying to over compensate for an air leak. Idle speed if at 12-1500 hot is too high for an MOT.

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Tue 15 Mar 2011 17:10
ford mondeo mk2 1800 - mondeo idle/emissions & brake pedal travel problem - daniel79

Hi,

The discs and pads were new, i've seen people try to fit second hand brake friction too - it nevers ends well!! The rear drums don't look too bad - but, no the brakes have not been pressure bled, don't have the tools for that, only a bit of pipe, one way valve, jam jar and a willing helper... I was getting a good flow of brake fluid with no air bubbles in, but i am used to working on much older stuff (1960's & 70's). Is there a diy kit available to pressure bleed or is it a garage job?

as for emmissions, I have checked for leaks, but can't find anything obvious - the plenum seems to be bolted down properly and all the pipes attached - gave all the clips a tighten just in case. There was however only a rubber gromit in 1 of the 3 plenum bolts, would these cause a leak? the bolt holes looked separate from the air intake which still has its o ring in place. The temperature gauage doesn't work (well, sometimes the needle will rise but then drops down again every so often) would this sensor be connected to the ecu too or just the temp gauge?

many thanks for your help

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Fri 18 Mar 2011 07:43
ford mondeo mk2 1800 - mondeo idle/emissions & brake pedal travel problem - daniel79

ok, it looks like the garge i took it too was being somewhat pedantic about the brake pedal - took it to another garage and in their words 'don't know what they are on about, its not a new car anymore'. i like this chap!

as for the emmissions, there was a breather pipe to the back of the engine, hidden under the inlet manifold (an absolute sod to get to) which had collapsed and sucked itself flat - not supirsed the engine was having trouble, replaced it and idle speed i back to 950.

just waiting on the results of the mot......

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Fri 18 Mar 2011 10:38
ford mondeo mk2 1800 - mondeo idle/emissions & brake pedal travel problem - injection doc

good luck with the MOT. You will be suprised how new drums enhance the pedal.

That little elbow pipe iether red or black is almost impossible to see but very common for iether splitting or collapsing. Right hand back end of head just above the gearbox bellhousing. I used to replace hundreds of thoses.

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Tue 22 Mar 2011 18:21
ford mondeo mk2 1800 - mondeo idle/emissions & brake pedal travel problem - daniel79

aarrggh! still can't get it through the mot! brakes are now fine, idle speed is fine - but high co in second fast idle test (.40 and should be .30)

no ecu fault codes, idle control valve working fine - is there anything else it could be before i replace the cat??

many thanks

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