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engine judder ?

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engine judder
2K views 1 reply 2 participants last post by  lizzard-t 
#1 ·
Hi, I have a 2009 Turbo editon 95 TiD auto 3 times in the last 6 weeks when on motorway at about 65-70 it has juddered, and seems to feel similar to a petrol engine dropping to 3 cylinders from 4. It will still keep up the speed ,and when you floor it it goes faster and clears but still "misses" when you drop back to 65-70, when you slow down to around 40 its fine. First time it lasted for approx 20seconds then stopped, a minute later 20 seconds then stopped, and after another minute approx 20 seconds. I pulled over to see if it was wheel related (puncture etc) started car and it was fine. Second time approx 2 weeks later the same happened for about 5 mins on and off and then was fine. Last time was last Friday while on holiday in cornwall, It really juddered and when I stopped at a junction and put it into N (automatic) it still "misses" like it was running on 3 cylinders. I pulled off the dual carriageway onto the evil Cornish country lanes and super steep hills and it was fine again. It has been fine since, I do 95% of my driving on long distance 140 mile round commutes to work 7 days on 7 days off, on the A40 and M40, no warning lights leaks or codes. Took it to my usual mechanic and he is baffled, no stored codes and checked with a snap on diagnostic computer. Bar this the car has been and is awesome. Could it be EGR, or exhaust gas temperature sensor, fuel rail or fuel rail pressure sensor or maybe 1 injector on the way out ?. Any help appreciated !!!!
 
#2 ·
Hello Monkey
has your mechanic, got the facility to do live data readings because it's so intermittent, could be playing guess the fault , until it actually happens,
or invest in opcom which is a good tool .
Either that or I don't know if some of thease obd readers that you plug into the obd socket ( dongles I think ) and you can down load the data onto a laptop may be better .
Sorry cant be much help
 
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