2006 Citroen C4 Auto | AL4 slipping in 1st gear eventually engages with a clunk, when warm

Cheers all, we ended up replacing the EVS3 + EVS4 electrovalves and also giving the car a cocktail of new Penrite Syn ATF + Lucas Oil Transmission Fix (24 oz) as recommended in other threads/sites. About 100 km later and the car seems to be running really well now, within that 100 km it seemed to improve over the first 20-40km.

Will keep an eye on it for another 250-500 km, I'll eventually have to sell it as it was never meant to be a "long term" car, it was only to fill in the gap between my old car Peugeot 306 and a newer car. It ended up being a much larger endevour than I first thought :spanner::spanner::spanner:

Just need to figure out what a fair price for it is in it's current condition.
 
Last edited:
Thermostat

1.6i
Commences 89 deg
Fully open 101 deg

1.6 HDI
Commences 83 deg
Fully open 97 deg
 
Thermostat

1.6i
Commences 89 deg
Fully open 101 deg

1.6 HDI
Commences 83 deg
Fully open 97 deg

Thanks for that, I've got the 2.0i. On Lexia3 I was seeing 110-114 degrees on the Engine coolant and the Gearbox was at 100 degrees. Seems a little hot to me.
 
Thanks for that, I've got the 2.0i. On Lexia3 I was seeing 110-114 degrees on the Engine coolant and the Gearbox was at 100 degrees. Seems a little hot to me.
That's not right. Both seem to be running about 20'C hotter than they should.
If it was one or the other that was high I might blame the sensor, but seeing as both are high I would say the cooling system is not operating correctly. The coolant temp sensors tend to go open circuit when they fail. Giving you a false over temp warning. However this is typicaly logged as a sensor fault as well. Over temp warning (the real over temp warning), typically, doesn't kick in until about 120'C.
Does it get hot out on the open road, or around town?
Here and there in stop and go traffic tends to be the thermo fans. But if they run when the aircon is on it's unlikely to be them.
All the time, tends to be the thermostat or water pump.
At high speed only, tends to be the radiator.
The thermostat is the easiest to get to and test. Make sure its fully closed when cold, then put it in an old pot of boiling water. It should fully open in a few seconds.
I might be tempted to change the thermostat on spec anyway.
The fins on a water pump can get damaged or corroded away if a corrosion inhibitor or anti cavitation additive is not used in the coolant. If the coolant has been maintained correctly damage to the fins is unlikely. However, different manufactures of water pumps make the fins out of thicker or thinner materials and the fins can break off inferior quality pumps.
The radiator can be capacity tested by a radiator mob, but if you have eliminated everything else, prepare to have the radiator replaced anyway.
 
Cheers all, we ended up replacing the EVS3 + EVS4 electrovalves and also giving the car a cocktail of new Penrite Syn ATF + Lucas Oil Transmission Fix (24 oz) as recommended in other threads/sites. About 100 km later and the car seems to be running really well now, within that 100 km it seemed to improve over the first 20-40km.

Will keep an eye on it for another 250-500 km, I'll eventually have to sell it as it was never meant to be a "long term" car, it was only to fill in the gap between my old car Peugeot 306 and a newer car. It ended up being a much larger endevour than I first thought :spanner::spanner::spanner:

Just need to figure out what a fair price for it is in it's current condition.
Hi Pug88,

I'm new on this forum and have a short question. I recently bought a 2004 C3 1.4i Exclusive Full automatic transmission. I'm having exactly the same issue as you have. When stopping for traffic lights after the car is running for about 30-45 mins, releasing the break pedal the car won't go in to 1st gear. It rather jumps in to the first gear after 2-10 seconds and I hear a chunk sound.

What would you advise me to do or ask the dealer to look at (Im not car mechanic so i'll have to bring the car to a dealer anyway)?
 
the dealer will most likelty advise a new transmission, you should start by changing then transmission oil, and probably the valve body
 
Surely there are independent mechanics or workshops in the Netherlands?

In Australia dealers don't always have the best reputation, and sometimes there solution will be the most expensive option. An independent Citroen (or Peugeot) specialist workshop will likely offer more affordable choices.
 
We sure have these independent car mechanics but they are often not specialised in certain brands. Rather just allrounders. I read that the automatic transmission (pnrd) in my car is quiete often used within different french cars. So i’ll be looking for a mechanic with knowledge of french cars. Also, i noticed that my car has an issue with the break light switch. Could that cause this issue?

many thanks both of you!
 
The AL4/DPO gearboxes are extremely "popular" and used across a wide range of Marques. In Europe, you should have no problem finding an independent repairer for the gearbox. I would take it to a gearbox specialist and not to a general mechanic.
The brake light switch has 2 independent sets of contacts. One set is dedicated to the actual brake lamps and that's all it does. The second set tells the entire CAN bus that you have pushed the brake peddle. This includes the engine, the ABS and the gearbox (maybe others). This tells the gearbox it may need to shift down and it tells the gearbox to unlock the 'park lock' mechanism. I do not know if it effects the gearbox while the car is not moving. I doubt it would be contributing to your problems.
My brake switch failed and randomly engaged and disengaged the park lock. Meaning, sometimes I could and sometimes I couldn't get the shift lever out of park. However it never seemed to effect the performance of the gearbox per se.
 
Hi, I helped Pug88 with this issue, both of us being new to older European auto transmissions we went through what we thought was a systematic process - noting that the first gearbox had a mechanic change the two main electro valves and check the box, then giving us a diagnosis of a worn internal oil pump (gearbox @ 118k kms), which sent us down the route of changing out the box with a box from a car we had as a spare with relatively unknow history. Also worth noting we're in Australia, NSW.

Sequence of events:
1. Original gearbox goes into limp mode. (let's call this C1 gearbox)
2. Mechanic changes "main pressure regulation valve" and "convertor pressure valve"
3. Mechanic makes the call that after changing valves that the internal oil pump is badly worn.
4. We have a spare car with 200k kms on the clock. (Citroen C4 2007, identical car, even the same color)
5. Remove gearbox and install it into our car ((let's call this C2 gearbox)
6. C2 gearbox now in car and has an issue changing from 2nd to 1st.
7. Symptoms lead us to believe is may be an issue with valves 3&4.
8. Remove valves from C1 Valves and install into C2 box.
Note: at this stage we have not removed the valve body, only harvested valves 3&4 from C1
9. Carry out ATF oil changes, 4 off oil drains and fills to get the ATF as clean as possible. C2 is running better but still has the initial fault of hesitating from 2nd to 1st.
10. Add Lucas Oil Transmission Fix (24 oz) - C2 runs better but the issue is still there.
** Pug88 has purchased the Lexia3 and we've carried out as much checking as possible.
** we also swapped the gearbox computer out from the donor car to see if that was an issue - no change.
11. At this stage we concede that the box has a mechanical issue and is most likely a worn transmission brake band.

Then comes the lightbulb moment, I decided to pull out the valve body from C1, I had always had a question mark as to why would a box with only 118k kms would have a worn pump? I was also going to split the box, pulling out the valve body I find that the two electro-valves the mechanic has changed are "loose", and by loose I mean finger tight. It appears he has installed the two valves, probably been called away or distracted, installed the valve body, run the car, tested with his analyzer and diagnosed low oil pressure. As the gearbox was run with the valves loose, the oil pressure bypassed the valves and blew out the seals / seal covers.

This is the point where we head down a rabbit hole of changing out and re-changing out gearboxes. After discussion with the mechanic, and I'll say he was very apologetic and possessional about it, I asked for 2 new valves, and the money back from the original service, he was compliant and we left on good terms. So I now have two new electro-valves and enough money to by $150 worth of Penrite FS ATF.

Remember at this point we still have gearbox C2 in the car, C1 sitting on the ground with a valve body with two faulty/incorrectly installed valves.

12. Install new electro-valves to valve body after giving it a clean and once over.
13. Install gearbox C1 (original box).
14. Carry out ATF fluid changes.

And a hint, Removing the front subframe does make changing the box out easier, I did two changes with the sub frame in and 1 with it out.

Car has now been running for over 800kms with no issues, gearbox changes are smooth, and the box is behaving like you'd expect a 2006 4 speed auto to behave.

It's a pity we were between a rock and hard place (we'd only had the car for 6 weeks) when we first got the diagnosis of a worn oil pump post valve changes, at that stage we couldn't find a 2nd hand box with warranty - wreckers hotline had one is SA, but it would have been a $1800 outlay, a rebuild was quoted at $5k. So the only option for us was to take a chance on the donor box C2.

So in summary, a mechanics (independent French car specialist) mistake lead us to remove C2 gearbox twice, C1 gearbox twice (once because I dropped a convertor bolt behind the flywheel on install), and install a box 3 times. We certainly know how to change a C4 AL4 auto gearbox now. Thanks for all the input from the froggies.

This closes the chapter (hopefully) on our gearbox issues!
 
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Hi, I helped Pug88 with this issue, both of us being new to older European auto transmissions we went through what we thought was a systematic process - noting that the first gearbox had a mechanic change the two main electro valves and check the box, then giving us a diagnosis of a worn internal oil pump (gearbox @ 118k kms), which sent us down the route of changing out the box with a box from a car we had as a spare with relatively unknow history. Also worth noting we're in Australia, NSW.

Sequence of events:
1. Original gearbox goes into limp mode. (let's call this C1 gearbox)
2. Mechanic changes "main pressure regulation valve" and "convertor pressure valve"
3. Mechanic makes the call that after changing valves that the internal oil pump is badly worn.
4. We have a spare car with 200k kms on the clock. (Citroen C4 2007, identical car, even the same color)
5. Remove gearbox and install it into our car ((let's call this C2 gearbox)
6. C2 gearbox now in car and has an issue changing from 2nd to 1st.
7. Symptoms lead us to believe is may be an issue with valves 3&4.
8. Remove valves from C1 Valves and install into C2 box.
Note: at this stage we have not removed the valve body, only harvested valves 3&4 from C1
9. Carry out ATF oil changes, 4 off oil drains and fills to get the ATF as clean as possible. C2 is running better but still has the initial fault of hesitating from 2nd to 1st.
10. Add Lucas Oil Transmission Fix (24 oz) - C2 runs better but the issue is still there.
** Pug88 has purchased the Lexia3 and we've carried out as much checking as possible.
** we also swapped the gearbox computer out from the donor car to see if that was an issue - no change.
11. At this stage we concede that the box has a mechanical issue and is most likely a worn transmission brake band.

Then comes the lightbulb moment, I decided to pull out the valve body from C1, I had always had a question mark as to why would a box with only 118k kms would have a worn pump? I was also going to split the box, pulling out the valve body I find that the two electro-valves the mechanic has changed are "loose", and by loose I mean finger tight. It appears he has installed the two valves, probably been called away or distracted, installed the valve body, run the car, tested with his analyzer and diagnosed low oil pressure. As the gearbox was run with the valves loose, the oil pressure bypassed the valves and blew out the seals / seal covers.

This is the point where we head down a rabbit hole of changing out and re-changing out gearboxes. After discussion with the mechanic, and I'll say he was very apologetic and possessional about it, I asked for 2 new valves, and the money back from the original service, he was compliant and we left on good terms. So I now have two new electro-valves and enough money to by $150 worth of Penrite FS ATF.

Remember at this point we still have gearbox C2 in the car, C1 sitting on the ground with a valve body with two faulty/incorrectly installed valves.

12. Install new electro-valves to valve body after giving it a clean and once over.
13. Install gearbox C1 (original box).
14. Carry out ATF fluid changes.

And a hint, Removing the front subframe does make changing the box out easier, I did two changes with the sub frame in and 1 with it out.

Car has now been running for over 800kms with no issues, gearbox changes are smooth, and the box is behaving like you'd expect a 2006 4 speed auto to behave.

It's a pity we were between a rock and hard place (we'd only had the car for 6 weeks) when we first got the diagnosis of a worn oil pump post valve changes, at that stage we couldn't find a 2nd hand box with warranty - wreckers hotline had one is SA, but it would have been a $1800 outlay, a rebuild was quoted at $5k. So the only option for us was to take a chance on the donor box C2.

So in summary, a mechanics (independent French car specialist) mistake lead us to remove C2 gearbox twice, C1 gearbox twice (once because I dropped a convertor bolt behind the flywheel on install), and install a box 3 times. We certainly know how to change a C4 AL4 auto gearbox now. Thanks for all the input from the froggies.

This closes the chapter (hopefully) on our gearbox issues!
Been there, done that, subframe out save plenty of time.
Well done on with the final outcome
 
Hi, I helped Pug88 with this issue, both of us being new to older European auto transmissions we went through what we thought was a systematic process - noting that the first gearbox had a mechanic change the two main electro valves and check the box, then giving us a diagnosis of a worn internal oil pump (gearbox @ 118k kms), which sent us down the route of changing out the box with a box from a car we had as a spare with relatively unknow history. Also worth noting we're in Australia, NSW.

Sequence of events:
1. Original gearbox goes into limp mode. (let's call this C1 gearbox)
2. Mechanic changes "main pressure regulation valve" and "convertor pressure valve"
3. Mechanic makes the call that after changing valves that the internal oil pump is badly worn.
4. We have a spare car with 200k kms on the clock. (Citroen C4 2007, identical car, even the same color)
5. Remove gearbox and install it into our car ((let's call this C2 gearbox)
6. C2 gearbox now in car and has an issue changing from 2nd to 1st.
7. Symptoms lead us to believe is may be an issue with valves 3&4.
8. Remove valves from C1 Valves and install into C2 box.
Note: at this stage we have not removed the valve body, only harvested valves 3&4 from C1
9. Carry out ATF oil changes, 4 off oil drains and fills to get the ATF as clean as possible. C2 is running better but still has the initial fault of hesitating from 2nd to 1st.
10. Add Lucas Oil Transmission Fix (24 oz) - C2 runs better but the issue is still there.
** Pug88 has purchased the Lexia3 and we've carried out as much checking as possible.
** we also swapped the gearbox computer out from the donor car to see if that was an issue - no change.
11. At this stage we concede that the box has a mechanical issue and is most likely a worn transmission brake band.

Then comes the lightbulb moment, I decided to pull out the valve body from C1, I had always had a question mark as to why would a box with only 118k kms would have a worn pump? I was also going to split the box, pulling out the valve body I find that the two electro-valves the mechanic has changed are "loose", and by loose I mean finger tight. It appears he has installed the two valves, probably been called away or distracted, installed the valve body, run the car, tested with his analyzer and diagnosed low oil pressure. As the gearbox was run with the valves loose, the oil pressure bypassed the valves and blew out the seals / seal covers.

This is the point where we head down a rabbit hole of changing out and re-changing out gearboxes. After discussion with the mechanic, and I'll say he was very apologetic and possessional about it, I asked for 2 new valves, and the money back from the original service, he was compliant and we left on good terms. So I now have two new electro-valves and enough money to by $150 worth of Penrite FS ATF.

Remember at this point we still have gearbox C2 in the car, C1 sitting on the ground with a valve body with two faulty/incorrectly installed valves.

12. Install new electro-valves to valve body after giving it a clean and once over.
13. Install gearbox C1 (original box).
14. Carry out ATF fluid changes.

And a hint, Removing the front subframe does make changing the box out easier, I did two changes with the sub frame in and 1 with it out.

Car has now been running for over 800kms with no issues, gearbox changes are smooth, and the box is behaving like you'd expect a 2006 4 speed auto to behave.

It's a pity we were between a rock and hard place (we'd only had the car for 6 weeks) when we first got the diagnosis of a worn oil pump post valve changes, at that stage we couldn't find a 2nd hand box with warranty - wreckers hotline had one is SA, but it would have been a $1800 outlay, a rebuild was quoted at $5k. So the only option for us was to take a chance on the donor box C2.

So in summary, a mechanics (independent French car specialist) mistake lead us to remove C2 gearbox twice, C1 gearbox twice (once because I dropped a convertor bolt behind the flywheel on install), and install a box 3 times. We certainly know how to change a C4 AL4 auto gearbox now. Thanks for all the input from the froggies.

This closes the chapter (hopefully) on our gearbox issues!
This was a great read! I'm trying to fix my issues with shifting from 1st to 2nd once transmission oil gets up to temp. I've ordered two new solenoids already but it also sounds like replacing EVS3 and EVS4 helps. I can't find these parts online though. Any idea on part numbers or links?

Do I also need to clean out the valve body? It looks like a daunting jigsaw puzzle that I'm afraid I wouldn't put back together correctly.

Thanks!
 
Cheers all, we ended up replacing the EVS3 + EVS4 electrovalves and also giving the car a cocktail of new Penrite Syn ATF + Lucas Oil Transmission Fix (24 oz) as recommended in other threads/sites. About 100 km later and the car seems to be running really well now, within that 100 km it seemed to improve over the first 20-40km.

Will keep an eye on it for another 250-500 km, I'll eventually have to sell it as it was never meant to be a "long term" car, it was only to fill in the gap between my old car Peugeot 306 and a newer car. It ended up being a much larger endevour than I first thought :spanner::spanner::spanner:

Just need to figure out what a fair price for it is in it's current condition.
Hi, do you have part numbers or links for the EVS3 and EVS4? I can't find these online. I assume they're different to the main two solenoids.

Thanks
 
all the solenoids are secured by 1 x Torx screw. You need to remove the valve body to replace the main solenoids so not too difficult to replace EVS3 and 4.

Dont try opening and cleaning the VB, I did wash one out in diesel to get the old build up by soaking in a bucket, but who can wait to dry out all the veins?

Make sure you take photos pre removal, and follow the instructions, dont move the gear lever etc, and torque the VB back on and set back up. refill the correct oil grade as per instructions and take for a drive.

fingers crossed
 
all the solenoids are secured by 1 x Torx screw. You need to remove the valve body to replace the main solenoids so not too difficult to replace EVS3 and 4.

Dont try opening and cleaning the VB, I did wash one out in diesel to get the old build up by soaking in a bucket, but who can wait to dry out all the veins?

Make sure you take photos pre removal, and follow the instructions, dont move the gear lever etc, and torque the VB back on and set back up. refill the correct oil grade as per instructions and take for a drive.

fingers crossed
 
Is that what the torx bolts are on the side of the VB? No need to open up the VB itself?
 

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