Citroen C5 - Citroen C5 1.6 Hdi engine jolts at 70mph

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Sat 28 Jul 2012 17:34
Citroen C5 - Citroen C5 1.6 Hdi engine jolts at 70mph - ricshe

No problems at all at lower speeds, but after about 15 minutes on the motorway at high speeds, the engine jolts suddenly. If you reduce speed it improves, if you accelerate it's not long before it does it again. I rarely drive on motorways, but first noticed it 6 months ago, and it has been getting increasingly worse. Last weekend, on a long journey it jolted frequently, especially if you went a smidge over 70mph.

Had a diagnostic done today, nothing obvious wrong.

Anyone got any ideas?

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Sat 28 Jul 2012 21:00
Citroen C5 - Citroen C5 1.6 Hdi engine jolts at 70mph - elekie&a/c doctor

Before getting involved with the engine control system,I would get the fuel filter replaced.hth

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Sat 28 Jul 2012 21:29
Citroen C5 - Citroen C5 1.6 Hdi engine jolts at 70mph - injection doc

also try driving with the AC off and see if it still jolts !

small engine big car, sudden load from AC pump

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Fri 18 Jul 2014 10:40
Citroen C5 - Citroen C5 1.6 Hdi engine jolts at 70mph - ricshe

2 Years on an this is still a problem. Full service has been done. New fuel filter etc. Happens with the A/C off.

I have since discovered that the engine will not exceed 3500rpm when under load regardless of selected gear, and will not go beyond about 3800 to 4000 rpm when stationary (out of gear). The engine is erratic at these speeds and jerks around until you reduce the rpm where it becomes stable again. This is not limp mode and there are no diganostic faults that the citroen garage could find. So the problem can be avoided by keeping the engine speed low - but this means you can't accelerate very quickly.

The ECU, EGR valve, crankshaft sensor, and MAP sensor have all been change with no effect.

Would be great if someone has an idea what the cause is or what to test to pin point the problem without too much cost.

Thanks in advance for your help.

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Fri 18 Jul 2014 13:06
Citroen C5 - Citroen C5 1.6 Hdi engine jolts at 70mph - dadbif
You don't have your speed limiter set at 70mph do you?
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Fri 18 Jul 2014 13:36
Citroen C5 - Citroen C5 1.6 Hdi engine jolts at 70mph - Peter.N.

How about the MAF sensor, that will limit the revs.

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Fri 18 Jul 2014 14:00
Citroen C5 - Citroen C5 1.6 Hdi engine jolts at 70mph - ricshe

Thanks for your advice. I have tried unpluging the MAF sensor and it makes no difference - so I doubt this is the issue? Also wouldn't you expect to see a diagnostic fault if a sensor was faulty.

Its definately nothing to do with speed limiter as it happens when out of gear.

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Tue 22 Jul 2014 15:10
Citroen C5 - Citroen C5 1.6 Hdi engine jolts at 70mph - Gibbo_Wirral

I had this problem on my Pug. It was the diesel temperature sensor. A diagnostic brought up fault code on the part, but reading the live data it was reading the diesel at being -50'c.

Changed it and not a problem since.

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