Hey all
Following on from a few previous posts I have had some results from my local ford garage regarding the hesitancy upon hard acceleration in my 1.25 Zetec-SE:
Apparently conflicting fault codes - one is a breather pipe and the other is a problem with speed sensor. They have cleared the memory and have asked me to come back in 500miles (40 cycles?) and have it tested again.
No charge this time - but I'm assuming next time there will be!
Moby.
Moby
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Life it too short to stuff a mushroom
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Why not just change the speed sensor, is it a long job? the codes may conflict but its not unknown to have two or three intermittent faults, changing the sensor should clear one.
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Will disconecting the battery for an hour reset my settings?
as mine is intermitent could this be the same?
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Interesting results. Can't recall ever seeing a fault code generated by a breather hose and the speed sensor is unlikely to cause your problem as the ecu sees it only as an indicator that the car is actually in motion to control functions of deceleration fuel shut off and kerb-idle speed. Does the car actually hiccup if you accelerate hard while driving or if you just rev it at the kerbside? A failing plug or lead can give a similar symptom, another possibility is the air mass meter.
Andrew.
Simplicate and add lightness!
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I really think people are diving in at the deep end here......a common 'failing' in these complicated days of computer-mamanged cars..
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What I meant to say was that I agree with Adam - HT Leads & Plugs appear the most probable cause
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The car only hesitates under load, flat-to-the-floor acceleration usually in fourth (but also in lower gears) around 4000rpm. When I am in fifth hitting around 90mph there is a small hesitation around 4000rpm, but again, I can drive through it. If I accelerate hard without flooring the throttle I can usually drive without any hesitation.
The car does not hesitate when revving it at the kerbside.
I have replaced all leads and plugs with Ford Motorcraft ones, and have had a recent oil change usuing the correct grade.
TIA
Moby.
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I am erring towards airflow sensor but my advice would be at this stage to let it run its course for a time to see if the problem worsens as it will then be easier to find. Then I would hook up an oscilloscope to the airflow sensor, O2 sensor, throttle position sensor and coolant sensor then go for a drive to establish whether the fault is amongst that group.Other possibilities include fuel pressure and volume,(pump regulator and filter) then voltage supply to system (relays, earths etc) so you can see it is not going to be a five minute or quick fix!
Andrew
Simplicate and add lightness!
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Thanks for that Andrew. Unfortunately this seems to be a job for the pros... I will be taking it back to Ford this Friday after completing the 500 miles they needed for the computer to establish fault codes.
I\'ll see what they say, although I imagine I will have to pay for this one!
I\'ll keep you posted!
Cheers
Moby.
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Hi,
I have exactly the same problem with my 1.25 '97 fiesta. I would be interested to know the outcome of your investigation.
My fault appeared over night after disconnecting the battery for a long period. Car was fine before, but is now really gutless.
If you have any info that may help me, I would be very grateful to hear it.
Fiesta man
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