2014 dv6 tdci focus hesitation misfire

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Dcunning35
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Joined: Thu Jan 28, 2016 12:33 pm

2014 dv6 tdci focus hesitation misfire

Post by Dcunning35 »

Hi I am having difficulty with a ford focus 1.6tdci 2014 .
The symptoms are stumble hestation misfire from cold start around 1500 to 2500 rpm
I have check everything ,fuel quality ,leakback ,frp,relative compression,actual compression,cylinder leakage.
looked at each injector {piezo} with current clamp and crankshaft and really tried to pin this to a cylinder .Ids shows no significant differences in cylinder balancing when checked serially.
With the help of stc we run a maths channel over this waveform and noted we couldn't see the misfire event? .what we did see is the ckp signal was increadibly hard to pick out at higher rpm the divisions appear to touch or overlap and I know for a fact the ckp tone ring has a real impact on the adaptive learning for pilot injection on this engine but when I checked a comparible vehicle in a known good condition the ckp signal behaved in the same manner .
If any one can assist me in locating the misfiring cylinder I would be grateful to say the least .
I will attach the good and bad waveforms . 2014 focus is bad ,2013 the good .... im the ugly lol well I need some humour today.
Danny
Attachments
Danny Focus.psdata
(1.86 MiB) Downloaded 755 times

Dcunning35
TwoWaves
TwoWaves
Posts: 238
Joined: Thu Jan 28, 2016 12:33 pm

Re: 2014 dv6 tdci focus hesitation misfire

Post by Dcunning35 »

please see bellow attached waveform of good vehicle .
Danny
Attachments
Ford_Focus_2013_Diesel_20160824-0001good.psdata
good vehicle
(4.62 MiB) Downloaded 1190 times

volrem
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Location: Estonia

Re: 2014 dv6 tdci focus hesitation misfire

Post by volrem »

Start by taking new measurement but increase your sample rate to get at least 1μs or faster sample interval.

At idle 5μs is manageable but when you raise speed then you sample rate is just too slow to measure this signal correctly.
At 50m/s timebase use 1MS sample rate.

Dcunning35
TwoWaves
TwoWaves
Posts: 238
Joined: Thu Jan 28, 2016 12:33 pm

Re: 2014 dv6 tdci focus hesitation misfire

Post by Dcunning35 »

Thanks for the advice Il give it another go next week as I finish for holidays tonight.

Dcunning35
TwoWaves
TwoWaves
Posts: 238
Joined: Thu Jan 28, 2016 12:33 pm

Re: 2014 dv6 tdci focus hesitation misfire

Post by Dcunning35 »

Update, the vehicle is now fixed after chasing my tail I re looked at the live data pids for the fuel injector pilot learns, these are a status counter 0 meaning not learned and 7 completed.
All four injectors displayed 0 .
I re run the pilot learning road-test after resetting the values and watched the pods status change to 7s .
The vehicle ran perfect after the learn so I left for a few hours to cool and re appraise.
Upon starting it ran lumpy and knocked and linked again like an old digger.
Revisiting the pods all sat at 0 again .
After checking pcm powers ,grounds , flashing pcm cal ,via calibration number and re running pilot learn same story after pcm powered down .

Replaced pcm , re run all learning and thank the lord , in the words of that geezer on strictly, 7 and no misfire.
Happy days
Thanks to all who offered advice on tho one again greatly appreciated.
Danny

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