Citroen C5 X7, Annoying jerking at light loads in slow moving traffic.

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Adam82
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Citroen C5 X7, Annoying jerking at light loads in slow moving traffic.

Post by Adam82 »

Hi all,
Hope we are all enjoying the long weekend.
Over the last few months I have serviced and replaced quite a few parts but this problem and another has not gone away and it’s really annoying.
Going to try and explain as best as I can.

Ever since I’ve had the car it’s jerky in slow moving traffic and up to 30mph.
It’s as if the car is in an intermittent anti stall mode.
It doesn't matter if i'm stationary or not if the clutch is depressed, the lightest of accelerator pressure will bump the revs up to 1300, (the rpm can be lower but it’s a fixed rev). The same events happen when in any gear, I have to slip the clutch in 2nd or 3rd as it’s impossible to drive smoothly in 1st if traffic is crawling.
If I keep this up I’ll be looking at replacing the clutch at 124k. I think it’s a SAC clutch too so not looking forward to spending additional money on the tool for this.

I’ve had diagbox connected and I can see both potentiometer signals. These are moving in a smooth linear fashion with no spraddic values over the full deflection range. I also moved the pedal by hand over the ranges where light loads and reves are required. I don’t see any number jumping to random values.
I initially thought this issue was temperature related but no, if it's a cold morning or the nice warm recent weather we have had, it makes no difference.

To finish I have checked all the pipe work visually and can’t see or hear any boost leaks.

VIN: VF7**************[VIN obfuscated, can be read by forum staff]

Any ideas?
Last edited by xantia_v6 on 24 May 2020, 20:59, edited 1 time in total.
Reason: mask VIN
ed_ronayne
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Re: Citroen C5 X7, Annoying jerking at light loads in slow moving traffic.

Post by ed_ronayne »

Hi Adam82

I once had a very similar issue on a Peugeot 406, 1.6 16 Valve.
Turned out to be the EGR causing the issue.

not sure of the X7 has the newer 8 valve variant of that engine

As a quick test disconnect the multiplug connector to the EGR valve at the right hand rear of the engine.
you will get an EML on the dash. but the car will drive as smooth as silk and confirm if your having the same issue.
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Re: Citroen C5 X7, Annoying jerking at light loads in slow moving traffic.

Post by GiveMeABreak »

He has the 16 valve 2.0 engine.
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Peter.N.
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Re: Citroen C5 X7, Annoying jerking at light loads in slow moving traffic.

Post by Peter.N. »

Both of mine seem to be a little erratic at small throttle openings, especially when cold. When I got the first one I was always stalling it pulling away, in fact I still do occasionally - could be something to do with the fact that my previous car was a Merc 220 diesel, a rubbish car in many respects but I couldn't fault the engine, it would pull a house down and would pull away with no throttle at all.

I thought that was responsible for me stalling the C5 but I have noticed it is prone to cutting out if you try to accelerate at very low revs. The second one I got is not so bad but still has a tendency to stall if you are not careful. My wife seems to manage OK but she probably revs them more than me. After 10 years of driving XMs and another with 406s I have got used to not having to rev them to pull away - and I don't like wearing the clutch out.

Peter
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Adam82
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Re: Citroen C5 X7, Annoying jerking at light loads in slow moving traffic.

Post by Adam82 »

Thanks for the comments.
It’s a 2011 2.0 16V HDI, 163PS
I'll pull the EGR system off this weekend and give it a clean if it needs it.
I forgot to mention, I notice that the car feels lumpy when it’s doing its DPF clean. With or without cruise control.
Does anyone else experience this?
Most of the time it runs really smooth and it’s such a comfortable place to be in.

I get around 560 miles, plus minus 20 miles out of a tank. So I presume it’s running well?
My record was in my old 1.4 16V HDI C3, 627miles from full to just the reserve light.

Adam.
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Re: Citroen C5 X7, Annoying jerking at light loads in slow moving traffic.

Post by Peter.N. »

Mine does a phominal fuel consumption, but I drive phenomenally slowly. I tend to stick to the nearside lane of the motorway but can exceed 70 mpg when you include a few speed restrictions. It averages just under 50 in the winter but nearer 60 mpg in the summer. I also live in a rural area and drive mostly there.

Peter
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Adam82
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Re: Citroen C5 X7, Annoying jerking at light loads in slow moving traffic.

Post by Adam82 »

Ok,
I actually got stuck in some bad crawling traffic on my way home this evening.
It’s doing it again...

The EGR system to my knowledge is working fine.

Looking in the parts manual, I think that either the clutch switch or position sensor is malfunctioning in the cold this winter weather. The cars system seems to be keeping it in anti stall mode while driving in first and second and is overridden when the speed is over 30 MPH.

Is there anything in Lexia that can show when anti stall is active and possibly the analog value output for clutch position?
I have seen the “on/off” values for when the clutch pedal is depressed or not but think this is only information coming from the clutch switch not the actual position sensor.

Any thoughts?
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Re: Citroen C5 X7, Annoying jerking at light loads in slow moving traffic.

Post by davscer »

Hi! I have a similar issue. Did you replace the clutch switch? Thanks.
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Re: Citroen C5 X7, Annoying jerking at light loads in slow moving traffic.

Post by Peter.N. »

My red one which was the worst, started to die on me on long steep hills, if you released the throttle it would pick up again. I suspected the fuel filter which when I removed it had a fungus like substance all over it. Replacing the filter made it worse, it would die on me and not start.

I eventually found that there was air getting into the fuel feed. I suspected that maybe the in tank filter was also clogged so removed and dismantled it, clean as a whistle, put it back together and it was fine for about 100 miles then started doing the same thing again also the poor starting and dying when pulling away was back.

I found that if I operated the fuel pump bulb there was obviously air in the system but I couldn't see any bubbles until I shone a torch through the clear bit of fuel line going into the fuel filter, I could then see a stream of tiny bubbles at the top edge of the pipe, you couldn't see them without shining a light through them. They were not there after I had the tank unit out but have come back again.

I haven't done anything recently on account of the weather and having another car plus the fact that we have hardly been out on account of the covid, but I suspect the fault is with the fuel tank connection because that was really all I disturbed and the air bubbles stopped for a while. The tank is venting so its not building up a vacuum. I will try to establish the problem as soon as the weather improves and I have now had my first covid jab so hoping I will be able to get out a bit more. 8-)

Peter
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Re: Citroen C5 X7, Annoying jerking at light loads in slow moving traffic.

Post by Steveo »

Hi all
This is a very interesting post and I am following it closely.
Mine has never really been right when setting off and I can see when I let the clutch out the rev counter drops like a stone and I find myself feathering the clutch to prevent a stall.
I had a problem a few nights ago when the car just stopped (engine) and when I started it up again after it turned over a few times I got the anti pollution error message on the screen
This disappeared after it was restarted one hr later but It hesitated at a junction and put the esp light up .
This also disappeared on start up and I have slight hesitancy on occasions but not all the time.
If I gradually increase the revs there doesn't appear to be an issue, I have no error lights on at the moment.
I have changed the fuel filter and it made no difference i have checked the additive level and I have just shy of 1 ltr left

Does anyone know if its Eolys or pat fluid please

What lovely can but frustrating when you can't find a solution to the problem .

Has anyone changed the clutch switch and its made a difference? What are the values / can the be checked & how

All assistance gladly accepted
Regards
Steve
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Re: Citroen C5 X7, Annoying jerking at light loads in slow moving traffic.

Post by Peter.N. »

Not had any dealings with the clutch switch but after I had changed the filter and disconnected the fuel lines from the tank unit, removed it and replaced it, starting was much quicker and it no longer tried to stall when I pulled away - which it had done since I bought it, since the air leak has returned so has the erratic behaviour.

Shine a bright light through the clear fuel pipe from underneath with the engine ticking over and see if there are any bubbles. Try squeezing the primer bulb before you start it after it has been standing overnight, it should immediately feel solid, if it doesn't you have an air leak.

Peter
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Re: Citroen C5 X7, Annoying jerking at light loads in slow moving traffic.

Post by Steveo »

Hi Peter
Thank you for the reply

I don't want to hijack someone else's thread but I think the more information we have the closer we will be to solving the problem.
Going back to the op I find when you are in traffic or moving slowly my car also tends to be jerky but I put that down to the gearing in the gear box, it just doesn't feel right compared to other vehicles

I will check for bubbles this afternoon, the car starts first time everytime whether it's freezing cold or extremely hot.
It's just annoying when setting off (sometimes) and the hesitation when calling for power but this is also sometimes.
One thing I did forget to mention in my last post was that the problem seems to improve slightly when premium diesel is used.

Regards
Steve
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Re: Citroen C5 X7, Annoying jerking at light loads in slow moving traffic.

Post by GiveMeABreak »

I use a 'premium' diesel at least every third tank fill-up. The additional cleaners and fuel improvers keep the injection system clean and negate the need for using standalone fuel treatments.

You'll find that Citroen even mention "Fuel Quality" (I can't remember the exact term now) or similar as possible causes for some engine faults.
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Re: Citroen C5 X7, Annoying jerking at light loads in slow moving traffic.

Post by Steveo »

Marc
Thank you
Further investigation required but its always raining on my days off (must be trying to tell me something)

Take care

Merry Chrismas to everyone

Kindest regards

Steve & Wendy
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Re: Citroen C5 X7, Annoying jerking at light loads in slow moving traffic.

Post by Peter.N. »

Mine doesn't like pulling below 1500rpm but they are both like that, you get a vibration. My XM's would pull smoothly from tickover but I get the feeling that the flywheel was heavier in them, a lot of modern diesels won't pull smoothly at low revs. The first indication I had of fuel starvation I had last year in Yorkshire when we were going up toward Tan Hill, if you have been there you will know its very steep, the engine almost died on me several times, for the rest of the time it was OK but when home, after I changed the filter my wife complained it was dying on hills - didn't do it to me but she is much heavier footed than I am - the rest you know.

It had always been hesitant when I pulled away especially when cold, often it would stall and didn't always start first time but for the 100 miles or so after I had taken the tank unit out it didn't do it - the investigation is ongoing I will post my findings when (and if) I find a cure.

Peter