Electrovalves AL4

[steeneren]

Hey there..

Does anyone know which type of electrovalves is in a C5 II 2006/2007 AL4 automatic ???

I'm having issues with my gearbox, and after replacing the oil pressure sensor, which didn't fix it, I took it to a Aut. Specialist for an Oilchange.
He was certain that my gearbox was equipped with the new 100Hz Borg Warner Electrovalves and therefor, it would be pointless replacing them.
The oilchange only made things worse, but only with a Cold engine.
The only thing left, is to change the gearbox, he said..

Well, I just need to be sure.

So if anyone knows, please speak up.


Sincerely

Steen

[Mandrake]

What are the symptoms ?

[steeneren]

Low Oil pressure causing the transmission going into limp mode..

But only when cold, 2 -3 times, then running smoothly.

[Mandrake]

Do you have a Leixa ? On an AL4 you can monitor both the selected (desired by the ECU) pressure and the actual measured pressure in real time. Seeing how this changes under different operating conditions might provide some further clues.

Silly question - are you certain the oil level is correct ? Low oil level might cause low pressure when cold but as the oil expands with heat the level will rise slightly and may be just enough to function. The procedure to check the oil level is very specific and must be done at a precise temperature, which requires a Lexia to measure it, if the garage that did the oil change did not have a Lexia they may not have checked the level at the correct temperature - "auto specialist" notwithstanding.

Other possibilities are a clogged filter or sticking valves in the valve block, although I think in the case of a blocked filter the pressure would start off normal but then fall after a few seconds/minutes. See this thread for an example of what I believe was a blocked filter: (no way to know for sure as I think the gearbox and maybe the car got scraped in the end)

http://www.frenchcarforum.co.uk/forum/v ... =3&t=41417" onclick="window.open(this.href);return false;

Other things to consider - what is the mileage of the gearbox, has it had any oil changes before the symptoms appeared, and how black was the oil that came out ? As they're "sealed for life" with no factory specified change interval it might never have had a change of oil, while the general consensus is that following the sealed for life recommendation causes premature failure of these gearboxes with regular changes dramatically prolonging their life.

If you aren't aware of any previous oil changes and the oil that came out was black, keep in mind that each drain only actually drains about 50% of the oil (the torque converter doesn't drain) so it takes three or four changes of oil (with a hundred miles or so driving between each change to mix the oil) to get really dirty contaminated oil back into a reasonably clean state through progressive dilution. So symptoms caused by dirty contaminated oil might not go away with just a single oil change.

Been there, done that with the 4HP20 in my Xantia (which uses the same LT71141 oil) which started off with totally black oil probably never changed before, and was starting to make nasty noises...(The problems I had took three changes for the symptoms to go away, the first change didn't make a noticeable difference)

If you're lucky a couple more oil changes spaced over a few weeks could help (if 3 changes in total don't help further changes probably won't) - with these sort of problems if the electrovalves have already been replaced oil changes are about all you can try other than pulling the box out to have it overhauled. As a last resort if all else failed you could try Lubegard RED as an additive with a fresh oil change. (Only the RED grade, not platinum or any of the others, and at your own risk)

Hopefully addo will appear at some point and comment as he's probably done the most work on the AL4 out of the forum regulars.

[steeneren]

Hey Mandrake

Thank you for your reply

I do have a Lexia and I've done a real-time check in the parameter section. A bit hard for me to figure out what´s normal, but when running idle the oil pressure showed about 2.5-2.65 and the preffered pressure was 2,7. doesn't really say that much i guess
when driving around while checking the computer nothing really looks abnormal. But then again the problem only appears when the motor is Cold. should try doing it when Cold then



About the oil level. I'm almost 100% certain that he knew what he was doing. He had been working with the AL4 several times but as he said: It's pointless to keep changing different parts on this type of transmission. To expensive!
He did know about the temperature, but NO, he didn't have a tester on it.
It has been running 210.000 with no oilchanges so the oil was of course pitchblack.

I haven't had the electrovalves changed because the mechanic was certain that the new type was allready installed. which was the reason I asked if anyone knows which type is in a C5 2006/2007

I will consider an Oilchange Again, but then I will have to do it my self maybe adding the lubegard, I'll look into that.
I've also read somewhere that replacing the Valve body maybe could resolve the problem..


Steen

[Mandrake]

I do have a Lexia and I've done a real-time check in the parameter section. A bit hard for me to figure out what´s normal, but when running idle the oil pressure showed about 2.5-2.65 and the preffered pressure was 2,7. doesn't really say that much i guess
when driving around while checking the computer nothing really looks abnormal. But then again the problem only appears when the motor is Cold. should try doing it when Cold then

The oil pressure will change depending on what gear you're in (1st and reverse need higher pressure) and also the amount of torque that the engine produces - the more torque the more clutch pressure it takes to resist slipping, while at low engine torques lower pressure gives smoother changes. It may vary with temperature too.

The important thing is not what the pressure is, but whether the measured pressure tracks the demanded pressure closely - how close is normal I don't know, but I would say within 5-10% is probably reasonable. Usually the problem would be that the pressure is lower than demanded by the ECU.

If it only does it when cold then yes try to get the Lexia on the car ready at the parameters measurement screen when you first start the engine (log in to the ECU with the key on but engine not yet started) and watch closely the two pressure figures.

Another thing to check is look at the freeze frame data for the fault code that is being logged - highlight the fault and press enter, it should take you to another screen that shows some recorded details of what the gearbox was doing at the time the fault was logged - including pressure, temperature, probably rpm, what gear it was in etc...

About the oil level. I'm almost 100% certain that he knew what he was doing. He had been working with the AL4 several times but as he said: It's pointless to keep changing different parts on this type of transmission. To expensive!
He did know about the temperature, but NO, he didn't have a tester on it.
It has been running 210.000 with no oilchanges so the oil was of course pitchblack.

I'm assuming that's 210,000 kilometres not miles!! Even so it's at a mileage where you would expect to see problems with no oil changes. It's done well to last this far.

I haven't had the electrovalves changed because the mechanic was certain that the new type was allready installed. which was the reason I asked if anyone knows which type is in a C5 2006/2007

I will consider an Oilchange Again, but then I will have to do it my self maybe adding the lubegard, I'll look into that.
I've also read somewhere that replacing the Valve body maybe could resolve the problem..

There is a little bit about checking the oil level in the AL4 workshop manual here:

https://dl.dropboxusercontent.com/u/782 ... AL%204.pdf" onclick="window.open(this.href);return false;

(This is the Xantia version of the AL4 but the only differences are probably final drive ratio in the diff and ECU programming)

Somewhere on this forum is a thread involving Ben82 and Bandit12 where Ben was helping Bandit do an oil change on his AL4 so there should be some useful information there. From what I remember its not easy to do as the car needs to be on a hoist or over a pit to get underneath safely but still be level as the oil level is set by way of overflow through a level drain plug at a specified gearbox temperature.

[addo]

210K is good! The car deserves a biscuit.

The valve body is sensitive to accumulated fine material in the oil (especially when it has come from the steel parts), one fellow in Australia sells modified increased clearance solenoids to "mask" the issues.

If your line pressure is good from the pump (test with a gauge) and there is not excessive vibration from the converter, it's not time for a rebuild. You can dismantle and reassemble the valve body but it requires extremely fine tolerance work. If you go this way, be sure to understand the instructions very well and not to rush.

[MJM]

Are you certain that it's the AL4 transmission? My C5 facelift, 2007 reg has the 6 speed Aisin AW xxxx series fitted?

This one
http://en.wikipedia.org/wiki/AWTF-80_SC" onclick="window.open(this.href);return false;

[Mandrake]

Are you certain that it's the AL4 transmission? My C5 facelift, 2007 reg has the 6 speed Aisin AW xxxx series fitted?

This one
http://en.wikipedia.org/wiki/AWTF-80_SC" onclick="window.open(this.href);return false;

Good thinking, however check the Lexia screenshot steeneren posted - although its not in English BVA_AL4 is visible at the top.

[steeneren]

Yes I'm sure it's a 4 speed AL4

Did this video today:



Driving home from Work and 5.58 minutes in, the transmission malfunctioned.... I guess it's obvious when you look at the video.


Hopefully somebody can read something out of it

It's in Danish but I hope you know what it says, otherwise let me know and I'll translate


I'm thinkin about changing the valves and cleaning the valve body.
Since it has been running for 210K without oilchange, there must be some sort of dirt in there. And it's probably affected the valves in some degree.

[MJM]

Oops, must look at posts a bit closer!

[steeneren]

Hi all

Just a Little update...


I dicided to open up my gearbox in order to change my solinoids. It was the newer ones which was allready installed in the box, but I decided to change them anyway since the old ones has been driving around with dirty oil.
I opened up the valve block and did a thorough cleaning.
Assembled it Again, added Red lubegard and new gear oil.

Well.... the gearbox is running smoothly now, still a bit hard shift between 1st and 2nd when the oil is Cold.
But once the motor is heated up, everything is perfect..


I really hope it holds....

[Mandrake]

Fingers crossed, sounds promising.

After an oil change it takes a while for the old and new oil (and your additive) to mix and form a stable homogeneous mixture, so the hydraulic/mechanical characteristics of the gearbox will change slightly over the next hundred miles or so.

Also the ECU is auto-adaptive - when the gearbox changes mechanically/hydraulically (both the oil change and the valve block cleaning) the ECU will gradually "re-learn" the characteristics of the box, so you may find that after a certain amount of driving the gear shift from 1st to 2nd improves further.

Some gearboxes like the 4HP20 have an auto-adaptive reset function you can activate with a Lexia which will "hurry up" the learning process, but I don't think the AL4 has this option. (If it does it will be in the replacement parts section of the Lexia not under Diagnostics)

[steeneren]

Sounds Good with that auto adaptive thingy. It didnt had the reset function so I'll just have to wait and see.

[danielsydney]

Is the issue with this AL4 the torque in bigger engines? In the C3 1.4 the AL4 has never played up on me at all and is actually fine.