The 'we WILL fix this gearbox issue!' fault-finding thread!

[ex-derv]

yep, I got the right ecu from john but the 'new' box has issues changing up from 2nd - 3rd - it hangs slightly under load. When funds allow, I'll get a replacement gear set fitted in the original box and have it refitted.


EDIT: Thread split from original WTB thread!

[Davezj]

I think you thinking about the right thing, effectively doing a like for like auto box swap, or in you case get the original one repaired.

[ex-derv]

i've got a functional '97 box that I'm going to donor the gearset from to get my original box fixed - bit scared of the potential cost though

[elnevio]

yep, I got the right ecu from john but the 'new' box has issues changing up from 2nd - 3rd - it hangs slightly under load. When funds allow, I'll get a replacement gear set fitted in the original box and have it refitted.

That's exactly what mine does. Does yours do any of the things in D like mine doesn't? I.e. change down automatically when descending/coasting down a hill? And in D does it get into the highest gear as quickly as it can when under light load?

[Davezj]

That's exactly what mine does. Does yours do any of the things in D like mine doesn't? I.e. change down automatically when descending/coasting down a hill? And in D does it get into the highest gear as quickly as it can when under light load?

I think all auto boxes are supposed to change down gear when descending/coasting down hill as a safety feature. To stop the car running away down hill when the ecu detects no throttle and the speed increasing.
As for the going up to 5th as soon as possible, I think my car did that when I reset the auto box ecu (battery disconnect) and then went straight on to the motorway and did 30 miles or more. It changed up to 5th as soon as it possibly could at about 35 mph, and it almost missed 4th gear going straight from 3rd to 4th to 5th.
I had to reset the ecu again and drive round town in D to get it to change gear correctly.

Hope this could work for you.

[elnevio]

No Dave, mine *doesn't* have the hill descent control, as it were, any more. It also does not hold gears unless under WOT or heavy load.

[ex-derv]

mine doesn't change down anymore when descending a hill but it does go into fifth at about 35. A fluid change and ecu reset helped the other changes but the 2-3 change is still a bit sloppy. I flick the lever a little early and give it a little lift to encourage it. It's in D that it's bad though - hits the limiter in 2nd sometimes.

[elnevio]

Tim, I would suggest that as our symptoms are identical, our problem is also the same. I have also hit the limiter in 2nd while it's deciding what to do!

I also had the same problem with the 'interim' autobox (FL box with no external filter, but with OWC stamp and speed sensor output). I.e. exactly the same, and thus the gearbox can be ruled out as the problem. I definitely have the matching gearbox and ECU (I even have the matching engine! ), and a 7203 engine ECU.

Along with something Peter mentioned a while back to do with Keith's autobox, it seems that the problem may lie with the PFL AYC ECU, as that also has the control systems for the ASC/TCL. My TCL light flashes, unless I turn the TCL OFF manually. But the ASC still works (well, I say works, interferes when you don't want it to!) as it did in the good old PFL days.

So, I believe the fault may be fixed by replacing the AYC ECU with the facelift one. There may be an issue however with requiring the loom that goes with it though, as it may be slightly different.

[elnevio]

There may be some slight differences due to fluid level (I have a minor ATF leak to sort! ) but I bet you also get occasional sharp changes from 1 to 2 at low speed, and the change from 4th to 5th is really quick, and you wish all the changes were that good?

[ex-derv]

thats very interesting Nev - Dave suggested a while ago that there may be a TCL issue. My car doesnt have switchable TCL - does that mean it would need a different AYC ecu from yours?

[elnevio]

It should have a TCL OFF button by the driver's right knee?

[elnevio]

Do you at least have the TCL OFF light on the dash?

[ex-derv]

no button down there except the winter pack switch and I don't recall seeing TCL lights of any sort on the dash

[elnevio]

Skiddy car light? The TCL OFF light would have been next to that, and lights up (well, should) upon start up.

[ex-derv]

bare with me - I've just takem a photo of the dash lights...............

[elnevio]

(is it sad that this is exciting?)

[ex-derv]

IMAG0630 (1).jpgIMAG0634.jpg

[ex-derv]

(is it sad that this is exciting?)

I must confess to being semi-excited

[Davezj]

Sorry nev miss read the doesn't.

Tim car has the FL ASC system no TCL e.g. No grey canister, solenoid valves, no tcl switch, no tcl light.
It is a bit of an odd one. But a mate of mine in Liverpool has the same setup.
Maybe it is just a pfl with no TCL. was TCL an option on pfl and most people had it.

[elnevio]

That's interesting - you don't even have a skiddy car light? I wonder if the bulbs have been removed? Perhaps a previous owner had an issue and the lights were on?

The thing is, I am certain that no PFL autos left the factory (including COTYs) without ASC & TCL - I don't believe it could be unoptioned.


I take it you have the grey canister on the bulkhead? And if you floor it out of a wet T junction, you can feel the car pulling the power a bit?