Citroen XM Forum

Good news regarding your shift points though, not really right as Chris has said 3rd should come at 30mph and 4th at 40mph, mine shifts at these speeds then holds till about 27mph and 35mph before shifting back down, it sounds like a regulator fault but if the box shifts smoothly with no slipping and your happy with the performance i would not worry about it at all. It could of course be that the boxes in derv's had different regulators to allow for the extra low down torque but i doubt it.

Edit.....i forgot, yours is a TURBO diesel, you may well find that the autobox senses boost, the boost sensing pipe goes into the front of the box on the R/H side, it does on the TCT's so this could be a genuine characteristic of the box rather than a fault
D

That's interesting, I didn't realise that the box used boost pressure as a means to influence gear choice, I feel that the fact that the car is low on boost currently could well be influencing matters, particularly as a given throttle movement is not going to be resulting in as much go as would be expected. It's comforting to know that if I do have a regulator fault it isn't something to worry about (and no, the box certainly does not slip) although hopefully once I sort the boost issue, ratio selection will be sharpened.

Congratulations Johnathan,

You have got your self a nice XM there. I run a 2.1 Turbo D automatic, and it changes up into 3rd at about 33/34ish and chages up into 4th at 50. It will hold on to fourth to about 46ish, and hold 3rd to 31/30ish depending if the road is flat.

robert_e_smart wrote:it changes up into 3rd at about 33/34ish and chages up into 4th at 50. It will hold on to fourth to about 46ish, and hold 3rd to 31/30ish depending if the road is flat.

From memory, this pretty much describes what this car was doing even before it was treated to a well needed ATF change - so that's encouraging. Is it possible that the slight overfill could cause the short shift you're experiencing from 3rd to 4th?

Its certainly nothing to worry about, it will be the regulator if indeed there is a problem and as Lez demonstrated wonderfully recently its no real hardship to change, It does sound like a nice car though and its good to see its got a good home again.

D

Mine was overfilled for a while, and it didn't change the characteristics of the box, I just left it be, on the rationale that it was better having a little too much, that too little in it.

The boost gauge only going half way sounds about normal. Just adjusting the wastegate may not achieve anything as you probably need more fuel as well. The diapragm on the top of the pump is the on-boost fuelling control.

This is going to be a very simple quetsion, but should the gearbox oil level be checked with the oil warm (after a drive) or cold?

I always check it warm, it does seem to change the level quite a bit depending on cold or warm.

Dieselman wrote:The boost gauge only going half way sounds about normal. Just adjusting the wastegate may not achieve anything as you probably need more fuel as well. The diapragm on the top of the pump is the on-boost fuelling control.

No Id say thats not normal, but more a low boost result!

The SED Turbo, infact two of them here, BOTH go right over towards the end of the dial BUT NOT into the red!

Johnathan, Check intercooler hoses for possible splits! or leaks, I had a Xantia TD that was useless, but it turned out to be a split intercooler pipe! What a great result, I was ready to swap turbos too!

S2 owners dont know what their turbos give! They've NOT got a boost guage!

Paul

I always check it warm, it does seem to change the level quite a bit depending on cold or warm.

There should be two scales on the dipstick, one at 40c the other at 80c, ive always filled it cold on the 40c scale but after the next long drive checked the level at 80c just to be sure but either is fine really.

D