problems with AL4 automatic gearbox in a 2004 206 1.4

W

WJDijkstra

Member
Tadpole
Tadpole
Joined
Mar 11, 2024
Messages
31
Location
Jorwert
Hi everyone, We've got a bit of an issue with our 206.
The engine had low compression, so swapped in a "new" engine, and she now starts and runs great again.
I also changed over the AL4 gearbox over to the new engine. I did drain a bit of oil from the gearbox, and refilled with that same oil after refitting. Because I did spill a a bit here and there I added about 300cc of general atf oil. The first few miles were totally problem free.
However, when pushing the go-pedal down quite hard (I guess the box would downshift 1 gear), it suddenly lost all drive, and we coasted to a stop. We can hear a buzzing sound when shifting to drive or reverse, but we're not getting any movement. No errors or lights on the dash, and don't have access to pp2000 (yet).
Any idea where I should start troubleshooting this? Disconnecting the 12V didn't help ;)
 
It could be lots of things, but since you have just fitted the box why not check that work first?

Look at the electrical and gear change connections, the gear selector and the coolant connections. In short everything that attaches to it.

If that's OK, it's time for the heavy diagnostics. If you own a simple code reader, use that.
 
the simple code reader throws no codes, I have a pp2000 device on the way though. Will have a look after work, but thought I'd collect some ideas in the meantime! Did check the electrical connections etc, they all seem fine, gear selector moves, no coolant leaks. And it did drive for half an hour before this issue started...
 
So from cold now you have no forward gears how about reverse? Does the gear selector and dash display match I e N when in neutral, R when in reverse. Wiggle the gear selector in D drive make sure dash display not changing out of D
Also try use the manual selector and select 3rd rev to 2k does the car move now.

Did you open the valve body cover?

Too many things could possibly be wrong or faulty.

Hopefully some adjustments and correct oil flush can get you moving. I wouldn't be mixing old original oil with new....not sure what general ATF would be as box requires a suitable not random gear oil.
 
Just quickly checked:
totally no forward or reverse gear, also not in manual mode 3rd gear above 2k revs. gear selector matches the dash perfectly, not changing when wiggleing. Just the buzzing sound when in (any) gear, no buzzing sound when in Park or neutral. I haven't opened the valve body cover (yet). I only added 300cc of atf, thinking it wouldn't matter much on the 5 litres of original oil still in there...
 
the specs are also very close :
KROON ALMIROL
Dichtheid bij 15 °C, kg/l0,849
Viscositeit 40 °C, mm²/s35,80
Viscositeit 100 °C, mm²/s7,30
Viscositeitsindex175

Mobil ATF LT 71141
Density @ 15 C, g/cm3, ASTM D40520.855
Kinematic Viscosity @ 40 C, mm2/s, ASTM D44537.2
Kinematic Viscosity @ 100 C, mm2/s, ASTM D445
7.4
Viscosity Index, ASTM D2270168
 
WJDijkstra said:
However, when pushing the go-pedal down quite hard (I guess the box would downshift 1 gear), it suddenly lost all drive, and we coasted to a stop. We can hear a buzzing sound when shifting to drive or reverse, but we're not getting any movement.
Click to expand...
That could be a blown differential :(
 
just got pp2000 running, not measuring any oil pressure in the box. No oil pressure certainly causes our symptoms
:)

Any thoughts on where to begin to solve this?
 
Check the oil pressure sensor and wiring as this is fitted at the bottom of the auto box. Wiring can eventually be damaged or worn.... especially the Chinese replacement sensors. Also test at large grey connector fitted on top of the box
 
since I have been rolling the box around on the floor, supporting it from the bottom with a jack etc, it could definately be that I somehow damaged that part. Will dive into it and report back :)
 
Does sound like the converter wasn’t engaged into the pump properly…

Looks like the transmission and/or engine is coming back out again!

You “might” get lucky if you can undo the converter from the drive plate and see if you can push it back and engage it, but I’m tipping you’ve damaged the oil pump. What’s probably happened is you didn’t engage the two tabs on the converter with the pump, and the tabs jammed against the pump drive. The drive plate has enough flex in it that it allowed the trans to be bolted up the engine (did the pull the bellhousing onto the engine block using the bolts?) and the friction gave the pump enough drive for a little while. Then it broke…
 
When you split the engine and gearbox, did you leave the converter attached to the drive plate? You are not meant to do it that way. You are meant to unbolt the converter from the drive plate and leave it fitted to the gearbox. If the converter is removed, you are supposed to replace the seal.

Broken band perhaps? Someone may have the table for when the band is applied.
 
Haakon said:
Does sound like the converter wasn’t engaged into the pump properly…

Looks like the transmission and/or engine is coming back out again!

You “might” get lucky if you can undo the converter from the drive plate and see if you can push it back and engage it, but I’m tipping you’ve damaged the oil pump. What’s probably happened is you didn’t engage the two tabs on the converter with the pump, and the tabs jammed against the pump drive. The drive plate has enough flex in it that it allowed the trans to be bolted up the engine (did the pull the bellhousing onto the engine block using the bolts?) and the friction gave the pump enough drive for a little while. Then it broke…
Click to expand...
nope, that's not what happened. It did start out like that though, I pushed the box on the engine, engaged the bolts a bit, but because the box didn't go flush against the engine I didn't ram it all the way in. Unscrewed the bolts again, turned the torque converter a bit and it slid into the box another 15mm. After that I could just slide the box all the way up to the engine and I bolted it up like that.
 
David S said:
When you split the engine and gearbox, did you leave the converter attached to the drive plate? You are not meant to do it that way. You are meant to unbolt the converter from the drive plate and leave it fitted to the gearbox. If the converter is removed, you are supposed to replace the seal.

Broken band perhaps? Someone may have the table for when the band is applied.
Click to expand...
Was my first time working on an automatic gearbox, didn't know the torque convertor should stay with the box. Didn't replace the seal, but the oil is also not running out of the box (between the bellhousing and the engine). What does a "broken band" mean? And would I get get absolutely zero oil pressure with a broken band ?

@dimistyle what does that table mean? :)
 
Brakes in the table is internal bands, both would need to broken for no drive. Table shows which solenoid and which clutch is engaged when you actually have oil pressure. Any update on sensor condition? Otherwise more than likely the torque converter or valve body? Others may also have an opinion
 
You must log in or register to reply here.
Top