1991 4.0 Auto Limp Home Hell

What happened Maccadonna, did you ever get it sorted?

also try the auto gearbox repairers close to you and when you phone Marshall if they cant help ask them which gearbox people they use to use for the Jag

Thanks for the tip Michael, I'll give Swallow a call and try Marshalls of Cambridge which is a bit closer.

One day, one day I'll get into fourth gear......

Hi i haven't forgotten you but the only company that i know with the software to see what is going on is Swallows in London
the only other thing is get hold of jag and see if they still have it
sorry Michael

Sorry to bang on, but I'm desperate...

Just had the alternator soaked by a coolant leak which wasn't fun. However, while the alternator was on the fritz or producing very low power the gearbox worked fine.

Got the alternator fixed and now the gearbox limp home light is on again!

Anyone any ideas? Is there someway the gearbox ECU could be getting too much power and tripping out?

I'd appreciate any thoughts.

Thanks for your help guys.

Seems to be working intermittently now, but I think you're right and it's back to the garage. At least the mechanic will be able to afford a lovely summer break ;-)

Yep need some Help bring it up to speed

Hello Jaguarman!

I see you've been getting busy on here.

Hello Facelift

Hello Maccadonna,

It probably is still an auto gearbox ECU issue.

I had this on mine some years ago when the rain got in via a perished rubber seal around the back window pane.

They replaced the ECU but it was never quite right. On mine the gearbox still jumps a bit when it changes up to second even now. I've been able to live with it but I found out there's some fine tuning required after a replacement to get those ratios just right.

Back to the mechanic I'm afraid.

F.

Hi, thanks for the reply.

Based in Bury St Edmunds Suffolk. Anyone you could recommend would be great. Willing to travel.

Cheers

Hi well don't know where your based and don't want to up set you mechanic
but i would take it to a xjs jag man if you tel me where you are and i will see if i can find you some body

Hi,

I'm new to XJS s and this forum, but I was hoping someone might be good enough to offer some words of advice.

I fell in love with an XJS that overtook me as I pootled along in my tragic 1007 Puegoet on the motorway 6 months ago. As a result, I am now the owner of a 1991 4.0 Auto which I bought unseen (Iknow, I know..) on e-bay.

I bought the car with a known fault that it was intermittently on limp home mode, believed to be connected to a ABS return valve. Since I've had it it's been on about 95% of the time, and constantly for the last month. My local independent Jag mechanic has been over it with a fine tooth comb and finally assumed that it must be the auto ECU. He took it out and though a bit rusted it looked ok.

I found one on e-bay which didn't match the DAC number but I was assured it was a one size Fitz Hall. I've just replaced it with this shiny new one which fits perfectly but the bl**dy limp home light still clicks on a second or so after turning the key.

Is it worth trying to find a better matched ECU as I think (?) some changes were made circa 1991 or has anyone got any other ideas whatsoever? There seems to be a slight click coming from the ECU region a second before the light limp home light comes on.

I'd appreciate any thoughts advice as it would be good to know what it's like to drive an XJS in anything other than thrid gear!

Cheers,

Phil