Citroen C5 - Citroen C5 cuts out when changing from 3rd to 2nd

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Tue 10 Jun 2014 12:49
Citroen C5 - Citroen C5 cuts out when changing from 3rd to 2nd - Tethersend

This problem was discussed previously by French Paul but no solution stated. Car cuts out only when REDUCING speed i.e. for lights/junction, etc. That is, if I first accelerate to increase speed then change down a gear (or two) with enough time to decelerate to about 5-10mph in 2nd gear before needing to dip clutch and stop, then the car will tick over without cutting out. Otherwise it will cut out dead, needing the ignition key to be turned right off, then it usually starts up and ticks over as normal until next time.

What solved the problem French Paul, or anyone else who knows?

By the way, this is a 52plate 2.0 HDi

Edited by Tethersend on 10/06/2014 at 12:57

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Tue 10 Jun 2014 13:34
Citroen C5 - Citroen C5 cuts out when changing from 3rd to 2nd - SteveLee

Hook up an ODBC reader and check that the throttle position sensor and road speed sensors are functioning, the car may think it's coasting on a closed throttle at which point it will shut fuel off. Although I don't know how the road speed sensor could give a false positive reading.

To reiterate most modern cars shut off the fuel injectors completely when the car is in gear with no throttle applied. when the car senses any throttle input or the car or engine speed drops below a certain parameter or the clutch is dipped (on some cars), fuel injection will be resumed to prevent stalling.

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Mon 16 Jun 2014 11:43
Citroen C5 - Citroen C5 cuts out when changing from 3rd to 2nd - Tethersend

Many thanks for your advice, SteveLee. I'm sorry for my delay in response. I've had a local mechanic read the fault codes, which suggested camshaft and crankshaft sensors not communicating. However, I and he think you're right about the throttle position sensor causing the problem. It seems new sensors are only available from Citroen , costing about £250. This is shocking to me, so I've decided to try a used part from Ebay for £20. Of course, there's a chance that it could also be faulty but I think its worth trying. I'm awaiting delivery but I'll let you know how this goes.

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Mon 16 Jun 2014 13:58
Citroen C5 - Citroen C5 cuts out when changing from 3rd to 2nd - Peter.N.

I have used ebay parts on my C5 and they have been OK, if not they are cheap enough to buy another one. If you peplace a part and the fault is still the same its unlukely that the part is faulty, they usually bering in some different fault. Worth a try anyway.

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