Reports of my gearbox's good health...

[bukko]

...may have been exaggerated.

In other words, it's still facked.

But here's the weird thing. It's ok when I first drive it from cold but after 5 mins or so gets very lumpy (there's a clear imprint of my face on the inside of the windscreen).
Then if I pull over somewhere and turn off the engine, then back on, it's fine again, sometimes for just 5 mins but sometimes for much longer.

Is there some kind of sensor or something that gets reset that could be the problem?

 

[zefrench]

First step would be to take out the voltmeter and measure the selonoids resistance values. If your search the forums you will find them.

Google also:
Jatco JF506E part 1 PDF

 

[teddywood1]

ASK Hippo

 

[englishbullterrier]

Box of Swan Vesta ?

 

[Nodge68]

Check the solenoid resistance. Hippo has done a lot of research into the Jatco box. It's all here somewhere

 

[bukko]

Well, all gears are affected, so thinking it unlikely that all would fail at once I replaced the line pressure solenoid (which affects them all).

Is it likely that the others have failed as well?
I'll measure them at the weekend (when it's daylight) just to be sure anyway.

Thanks for the replies!

 

[zefrench]

If you want to troubleshoot the Jatco JF506E, the best document I have found so far that explains its inner working is


Self-Study Programme 232 5-Speed Automatic Gearbox 09A/09B


Google this pdf, and start reading. Volkswagen Calls the Jatco JF506E the 09A.

Lots of posts on the VW forums regarding this transmission that apply to us as well (Piston, Selenoid etc)

Let me know if you want more reading, I can see what I can dig up.

I also heard ATSG sells books/pdf for the transmission rebuild, not sure how good they are for troubleshooting.

 

[bukko]

If you want to troubleshoot the Jatco JF506E, the best document I have found so far that explains its inner working is


Self-Study Programme 232 5-Speed Automatic Gearbox 09A/09B


Google this pdf, and start reading. Volkswagen Calls the Jatco JF506E the 09A.

Lots of posts on the VW forums regarding this transmission that apply to us as well (Piston, Selenoid etc)

Let me know if you want more reading, I can see what I can dig up.

I also heard ATSG sells books/pdf for the transmission rebuild, not sure how good they are for troubleshooting.

Really good tips, thanks!

 

[Nodge68]

I'm thinking that maybe a sensor is going down when it warms up a bit. Turbine speed sensor maybe?

 

[bukko]

I was starting to think maybe the Torque Converter Lockup solenoid (N91) because that also would affect every gear.
Maybe it isn't releasing properly before changing gear? That would certainly make for nasty changes!
The trouble is, that could also be a faulty control unit, in fact more likely to be given the "reset" effect.

Maybe a faulty speed sensor could do the same thing, i.e. causing lock-up when it should be released?

I'll have to try to find ways to test all of them I guess!

 

[zefrench]

Hippo made a great video on the testing of the selenoids.

https://www.youtube.com/watch?v=VTmdkDuKZ6A

 

[bukko]

Yup saw that one thanks.
Will give it a go at the weekend, meanwhile just theorising

 

[bukko]

Measured all the solenoids today.
All seems to be ok.
Weren't exactly the same as Hippo's but pretty close and consistently so across the board, so I think I can put the differences down to temperature and accuracy of my multimeter.
I would assume that just because they measure ok doesn't mean they are ok.
Not sure where to go from this point though.

 

[Nodge68]

I was starting to think maybe the Torque Converter Lockup solenoid (N91) because that also would affect every gear.
Maybe it isn't releasing properly before changing gear? That would certainly make for nasty changes!
The trouble is, that could also be a faulty control unit, in fact more likely to be given the "reset" effect.

Maybe a faulty speed sensor could do the same thing, i.e. causing lock-up when it should be released?

I'll have to try to find ways to test all of them I guess!

It's not the TC lock solenoid as that only locks the TC in 4th and 5th, when the engine is at running temperature.
I'm thinking, it's a speed sensor breaking down once hot. Can you find someone near with a Hawkeye?

 

[bukko]

I guess I could bite the bullet and take it to the local dealer...

Isn't there a list of Hawkeye owners on the forum somewhere?

 

[freelance]

it might pay you to seperate and clean the two barrel connectors, they are under the battery tray and clean them well before reconnecting, i think if you search previous post for F4, you will find some hippo photo's.

 

[zefrench]

Do you have a plain odb2 code reader ? Any code read with that ?

 

[zefrench]

How far are you from Ashcroft ? I would go there before a local dealer. Maybe it's better on you side of the Atlantic but here all a dealer does is change the entire transmission. Much better success with a transmission shop.