Stalling C4 1.6hdi

[Doo]

Am working on the car just now and about to change the oil.

I noticed (why I didn't spot it before I don't know ) there is an accumulater sphere on the front of the gearbox. Part of me is convinced that this is worn and cthat's why she's jumping into gear and crashing gears now and again. Only 1st and reverse though. Not all the time and there's no codes present.

Who's with me that at 13yrs old it needs changed

There really isn't any other issues with the car....

[Doo]

Well, I had a good look under the car as I did the oil & filter, CV boot, track rod end and new front discs & pads.

I saw a pipe going from the housing the sphere is mounted on, into the box so I can only imagine that the sphere is the "push" for the clutch as a replacement for a pedal.

I think I'm on to something. It would be nice to know if the sphere is dead, but judging by the way the car is crunching into gear (1st & reverse, although not always...) I am 99.9% certain that is what is causing the issue

[Doo]

Ok, so here are the parts for the clutch system on this piloted C4: It's a 6-Speed Piloted Gearbox.

A) Clutch Control Master Cylinder	B) Clutch Parts

Just let me know the item number(s) from Table A or B if you need any part numbers.

As for the jumping on startup - obviously that is dangerous and needs sorting sooner rather than later. I don't have a solution as personally, I walk run in the other direction when I see one of these systems

I won't even start to advise what could be wrong as it is likely to be expensive whatever it is withe these as the labour is over 2.5 hours just to replace the actuator. But I would suggest you ring the guys at Euro Car Care (not to be confused with Euro Car Parts!). I know they have worked on these systems when they fiorst came out on the earlier C series models, so it may be worth having a chat and explaining the lunging issue on engine start.

But in the meantime, I strongly suggest you advise Mrs Doo to park on a runway for now just in case

Hi there, I bought oil for the box and intend on doing it...sooon

However, I am unsure of draining the oil & refilling. I haven't been under it for a bit, is there drain a plug & fill plug?

Also, does draining & filling require any input from the Lexia/Diagbox? I plan to give it a 15 mile round trip to warm the oil for ease of draining and the new oil will be warmed before filling. That's the easy part.

I also think the sphere on the gearbox should be replaced. Again, will swapping that out require any input from the computer to reset anything?

I have searched high and low, but can find NOTHING pertaining to our car & it's symptoms which are still trying to leap forward while being started or jumping into gear for no reason.

Is it possible the clutch is worn? It doesn't seem to act like it as it pulls very strong in all gears, even towing the caravan and 4 passengers. No slippage to report and we didn't hang around. There's 90k on the clock.

Could it be the clutch actuator is jamming? I really can't believe that....

I am certain it is an electrical issue because these boxes won't go into gear unless the stick is moved from Neutral and they shouldn't be in gear while being started, let alone jump forward. Also, to remind anyone interested, the car has twice been idling in neutral when it suddenly jumped into gear and stalled. Both times it was after towing the caravan over 15 miles. That leads me back to oil... Is there some electro valves that might be an issue?

Where will I get a sphere for the gearbox as I can't find one

Thanks all.

Edit, I meant to add a new twist to the tale. A couple of times now, while starting the engine it appears to be in gear and trying to start but stalling (wife's description) and then the dash goes to factory setting! So I have to go put it back to MPH and so on. My wife is European so is able to convert KPH to MPH so she can get to work safe But still.... So that would also point to an electrical issue, but the battery seems to be producing enough volts and amps, although I haven't yet tested it while cranking. Another pancake on the pile

[GiveMeABreak]

I’ll try and get a fuller answer later as I’m not on my rig at present, but regarding the oil, you can’t just top it up. The hydraulic system needs to be depressurised before topping it up and checking the level.

[Doo]

I’ll try and get a fuller answer later as I’m not on my rig at present, but regarding the oil, you can’t just top it up. The hydraulic system needs to be depressurised before topping it up and checking the level.

Just to be clear, I want to drain & replace as opposed to top up. Thanks

[GiveMeABreak]

Yes. Same thing, the system must be depressurised before you do any work including draining and refilling.

[xantia_v6]

It's not clear whether we are all discussing changing the gearbox lubricant or the hydraulic control fluid.

[Doo]

It's not clear whether we are all discussing changing the gearbox lubricant or the hydraulic control fluid.

Well, gearbox oil to me is the oil that lubricates the gears in the box.

Hydraulic control fluid sounds to me like it would have something to do with the clutch operation (is it actual hydraulic oil or brake fluid?)

I thought I was being clear. Apologies if I wasn't

[Ceenine]

A fascinating and frustrating problem.

When I top up the hydraulic fluid I don’t bother depressurising this system. I believe you would need to do that only when you are completely replacing the fluid. Car is still working fine after 14,000 km.

I will be following this topic with great interest. I am intrigued by your towing a caravan. What is its mass?
Don

[Doo]

A fascinating and frustrating problem.

When I top up the hydraulic fluid I don’t bother depressurising this system. I believe you would need to do that only when you are completely replacing the fluid. Car is still working fine after 14,000 km.

I will be following this topic with great interest. I am intrigued by your towing a caravan. What is its mass?
Don

It started life at 1100kg, but I rather think, like me, it's put on weight I imagine it's closer to 1200kg or so. Our car is rated for aprox 1560kg or thereabout.

[GiveMeABreak]

A fascinating and frustrating problem.

When I top up the hydraulic fluid I don’t bother depressurising this system. I believe you would need to do that only when you are completely replacing the fluid.

I'm only concerned with providing the correct guidance where it is known Don - and in the case of properly checking the oil and topping it up, the system needs to be depressurised - otherwise it is impossible to correctly gauge how much oil is in the system and this can lead to over-pressurisation when the system is finally pressurised. The operating pressure of the actuator is 37 BAR / 537 PSI.

As Doo is talking about removing the Accumulator Sphere on the Gearbox Actuator, it is the hydraulic actuator I am referring to regarding the checking and topping up of the oil.

Hydraulics Reservoir

Operations to be performed	Removing - Refitting	Replacement	Check the oil level - Topping up the oil level	Changing the oil
Reading of the counters	No OK	No OK	No OK	No OK
Writing of the counters	No OK	No OK	No OK	No OK
Depressurisation of the piloting actuator	1 (Before removal)	1 (Before replacement)	1 (Before check)	1 (Before fluid change)
Pressurisation of the piloting actuator	2 (After refitting)	2 (After replacement)	2 (After check)	2 (After fluid change)
Bleeding of the air in the hydraulic circuit	3 (After refitting)	3 (After replacement)	No OK	3 (After fluid change)
Initialisation of the bite point	No OK	No OK	No OK	No OK
Programming of the piloted manual gearbox grille	No OK	No OK	No OK	No OK

Note: The numbers 1, 2 & 3 refer to the order the operations are done

[Doo]

A fascinating and frustrating problem.

When I top up the hydraulic fluid I don’t bother depressurising this system. I believe you would need to do that only when you are completely replacing the fluid.

I'm only concerned with providing the correct guidance where it is known Don - and in the case of properly checking the oil and topping it up, the system needs to be depressurised - otherwise it is impossible to correctly gauge how much oil is in the system and this can lead to over-pressurisation when the system is finally pressurised. The operating pressure of the actuator is 37 BAR / 537 PSI.

As Doo is talking about removing the Accumulator Sphere on the Gearbox Actuator, it is the hydraulic actuator I am referring to regarding the checking and topping up of the oil.

Hydraulics Reservoir

Operations to be performed	Removing - Refitting	Replacement	Check the oil level - Topping up the oil level	Changing the oil
Reading of the counters	No OK	No OK	No OK	No OK
Writing of the counters	No OK	No OK	No OK	No OK
Depressurisation of the piloting actuator	1 (Before removal)	1 (Before replacement)	1 (Before check)	1 (Before fluid change)
Pressurisation of the piloting actuator	2 (After refitting)	2 (After replacement)	2 (After check)	2 (After fluid change)
Bleeding of the air in the hydraulic circuit	3 (After refitting)	3 (After replacement)	No OK	3 (After fluid change)
Initialisation of the bite point	No OK	No OK	No OK	No OK
Programming of the piloted manual gearbox grille	No OK	No OK	No OK	No OK

Note: The numbers 1, 2 & 3 refer to the order the operations are done

Thank you for the above information... Although, I'm not 100% certain what to do with it I'm guessing it's a step by step guide.

Meanwhile, I plugged in (yet again) after changing the battery for a newer one that I had lying around for a Fiat 1.9 jtd. I charged it up on trickle for around 38hrs until the green "charged" thingy showed up in the round window

Car started without issue (always does for me though ) and I started the diagnostics with DiagBox. The ONLY issue I found was the previous glow plugs apparently not happy. Yet, when I went into the specific test for each circuit, they worked as expected! Whatever

Did a global test (see above) and it showed only the one fault.

I then went through each component test and tried each circuit and they all came back clean. I tested the clutch in and off, perfect working order

I tested electrical circuits, relays and buttons. NOT a PEEP showing fault!

I checked historical downloads and all 3 came back fine (diag only).

I did notice the gear selector was fine until the car had been running for a while (I think around 20 minutes plus) then I selected 1 and it graunched. After that, it was fine again.

It suggests either an oil failure and/or sphere problem. It's like trying to select a gear, but only pushing the clutch pedal half way... I am certain the sphere is the "leg" in the situation and in this case, the leg is somewhat short

So that suggests it's lost pressure through age or the heat build up is creating an issue, which would suggest the oil is losing viscosity through heat.

However, not one time did I feel as if the car was "trying" to start in gear

I am convinced the gyroscopic action of the flywheel (and possibly a dying battery) may have contributed to my wife's "feeling" of the car jumping forward when in fact it may simply have been the engine speed having been sufficiently low to make it drag past a certain point then speed up, making the whole car shudder as it was being cranked over. I have decided to go for a drive with her and have the computer plugged in and record live data to see what the gearbox is actually doing.

I couldn't find a single issue no matter what I threw at it

But , I fitted a decent recent battery and I "know" both my Jaguar XK8 and my Range Rover (both V8 auto's) instantly flag up gearbox issues as soon as the battery starts losing it's viability. I am crossing many digits that this battery helps the situation and that the status quo is returned at least until I can figure how to change the gear box oil

[GiveMeABreak]

The battery is so important on these modern vehicles as there are so many systems that rely on them. With age the battery may show the correct voltage for charging and at rest, but age and use will deteriorate its ability to hold that charge for as long as the capacity diminishes with age. So a battery over 5 years old is probably considered past peek to be honest and can frequently impact the vehicle's operation.

Fingers crossed you have the problem solved - but normally if there is a fault with the gearbox actuator, then a specific fault code will be logged.

[Doo]

The battery is so important on these modern vehicles as there are so many systems that rely on them. With age the battery may show the correct voltage for charging and at rest, but age and use will deteriorate its ability to hold that charge for as long as the capacity diminishes with age. So a battery over 5 years old is probably considered past peek to be honest and can frequently impact the vehicle's operation.

Fingers crossed you have the problem solved - but normally if there is a fault with the gearbox actuator, then a specific fault code will be logged.

Indeed, but none have been found. I do want to change the oil though.

I imagine Lexia will let me go more in depth than diagbox because there was no suggestion of how to do anything other than look for codes... Unless I am using it wrong?!

I can't remember how to input the code it want's. Is it RPO?? or some such? I was informed where to find it, but have forgotten

Can you help me with that, please?

Cheers.

Doo

[GiveMeABreak]

If this is for your C4 VIN ending 634, then your RPO is 11113 and this is what you enter after selecting the correct model.