W124 auto gearbox switch problem

[Mark Wheeler]

The economy/sports switch selector doesn't work on my 230TE estate. It's permanently in sports mode i.e. uses all 4 gears which tends to make you drive like an old lady (sorry not PC) but pulling away in 1st downhill has no street cred and is downright irritating!
Has anyone got any ideas regarding possible cause or solution?

 

[MotardMan]

Your car should pull away in 2nd, not matter what position the switch is in. In Standard mode, it will shift to 1st if you drop the hammer hard enough, but gentler acceration will use 2nd, even from a standstill.

If the box definately uses 1st all the timer, you have a different problem...

Best,

Jim

 

[Leylandp76]

Jim's right, 1st is only there for occasional use. Check the adjustment on the throttle position cable going to the gearbox - if you're getting 1st all the time the cable could be too tight, or else there could be a fault on the kickdown switch which is operated by fully depressing the accellerator pedal.

The cable adjustments are in Haynes, I think the general rule is that with the throttle closed there should be no tension or slack in the cable. To get it exactly right you might need to take a test drive and the occasional roadside stop with a spanner to turn it the extra 1/2 turn either way to get the gears shifting just right (slacker makes the gears shift up earlier, tighter makes it hold a gear for longer and select a lower gear sooner).

You mention that your S/E switch doesn't work - it can be taken apart and cleaned out. Mine didn't work when I bought it (gremlins used to own my car) so I took it out and took it apart to check it out. In my case it had been gummed up inside by spilt juice or something sticky, and had then fallen to pieces. I was able to clean all the components using a toothbrush and contact cleaner. I then reassembled it in and it now works fine. The whole job took 15 minutes or so.

Hope this helps...

 

[kid-jensen]

Guys,

Are there any hard-and-fast rules for checking if the Standard/Economy switch is working?

If it only changes the shift points, that's pretty difficult to tie-down.

 

[Mark Wheeler]

To clarify the problem, yes the car definitely pulls away in 1st from a standing start even with low revs. Does this help to narrow down the fault?

 

[Leylandp76]

I assume you mean with low throttle. The answer is maybe, but more data required.

Can you move the switch with a firm 'snick' from S-E and back again? ie is it physically broken? When mine was broken it sort of slid freely for about 5mm with no feeling of any corresponding internal action.

The next question is - at what revs does it upshift from 1st to 2nd, 2nd to 3rd, and 3rd to 4th?

And does it tend to downshift as you slow down?

 

[Mark Wheeler]

Driving at low speeds the box changes up from 1st to 2nd at 2000 rpm, 2nd to 3rd at 2500 and 3rd to 4th at 2800 rpm. The S-E switch has a firm 'snick' as you call it both ways but apart from that no noticeable reaction to drive or revs, and yes the box downshifts as I slow down.
Any clues?

 

[Leylandp76]

It sounds like your switch is fine. e the revs at gearshift, mine's a 300TE so the shift positions may be different, so I won't confuse things by looking up what mine are. Either way I think your cable's too tight. The reson it downshifts as you decellerate is that the throttle position cable is telling the box that you are applying throttle so it assumes you want to accellerate, not slow down. This results in a downshift.

You should be able to adjust it easily (Haynes explains exactly) but I'd suggest loosening it one turn and taking the car for a drive. If you see no difference, loosen it another turn and try again.

If it's a minor misadjustment this should be sufficient if you can 'feel' it to what seems right, or you could be a little more scientific and follow the haynes instructions however I still think the final adjustment has to be done on a worn box by trial and error.

Alistair

 

[Mark Wheeler]

thanks Alistair, It'll have to be trial and error as I can't locate a Haynes manual locally. But from what you say this should provide the desired result, incidentally I only managed to get a manual for my old 123 series, sadly sold on, from a specialist book outlet.
Are the 124 series (4 cyl) manuals readily available because my Halfords don't appear to keep them.

Thanks again, will post when adjustments made.
Mark

 

[andy_k]

Halfords should stock it - our local one certainly does.

If not shout at them and make them get it into stock

failing that check out the link below

http://www.haynes.co.uk/inc/viewmanual.asp?mt=3253

HTH

Andy

 

[Richard.Wilson]

Mark,
I've scanned the page from the manual if you need it quickly, file is 693Kb
Shall I mail it to you?....what address???

 

[Mark Wheeler]

Richard,
yes please, see address at the end of this message, please try not to snigger, this is what you get when your daughter sets up the a/c for you.

I also owe you a big thankyou for solving the problem I posted as 'stiff accelerator pedal'. I tried fitting a new pedal and lubing linkage as advised by other forum users, all to no avail. Then whilst searching through for other similar posted problems, hit upon your post 'notchy throttle', did exactly what you'd done, adjusted the screw by half a turn and result.
Thanks mate, weeks of frustration solved in 10 minutes, however like you I don't know what the exact adjustment is, but I can live with the fix, as is.
I hope I can be of help in the future.
Mark
Email: heidismumanddad@yahoo.co.uk

 

[Mark Wheeler]

Andy,
thanks for the Halfords link, have just placed the order.

 

[Andy]

Hi All


If you look closelyat the cable there is a pointer on the white plastic part of the cable. If you look closely at the end of the white plastic its actually coarsly knurled. If you turn this till the pointer is in the centre. You will see what I mean. Then this is the correct adjsutment. Although finer adjustment may be required if the cable has strectched some what.

It does sound like the cable is too tight. You could try disconnecting it and see what the box changes like then. To disconnect it you will need to give it a sharp tap with the edge of a large screw driver and it will come off the linkage

Hope this helps.

Regards

Andy @ www.mercedesservicing.com

 

[Mark Wheeler]

Hi all,
checked out the adjustment on the 'control pressure cable' as detailed (very clearly) by Andy, and Haynes manual arrived Saturday too so had illustrations to follow also.
Bad news is pointer is exactly over the groove, slack on the end of the cable by adjuster approx. 1mm is about right and if anything, the cable appears slack not tight. So I didn't bother disconnecting the cable as there seemed little point. So it doesn't appear to be a tight cable causing the problem.

Any other ideas anyone??

Mark

 

[Leylandp76]

Sorry, out of ideas now for your symptoms. There was another post from someone a while back mentioning that he had rewired his to always use first at takeoff. I therefore wonder if something like this may have happened with yours but this is pure conjecture. If your getting no change in behaviour between S and E modes then maybe the issue is somehow in the electronics, for example kickdown switch stuck on? Or some wires shorting somewhere in the S/E switch? It may be worth having a look, it's my best guess.

Incidentally I just changed the fluid and filter on mine, the shifts are smoother but I can still pick a hesitation between 2nd and 3rd. I guess that's as good as I'm gonna get from this box.

Alistair

 

[Mark Wheeler]

I'ts definitely a thought Alistair because it occurs to me that this is a reconditioned box, I'm not sure how long ago it was fitted or whether it was an MB garage. So it's just possible that someone's monkeye'd around with the wiring. I'll have a look in the service history to establish who & when, but not sure what I'm going to do with the information even then.

Help! :?
Mark

 

[MotardMan]

Not wanting to hijack the thread, but just putting a bit of info on here.

I just took my 300TE to Cornwall and back. It ran perfectly and does 130 mph (sorry MikeB ) no problem......

I was driving up the A30 and got caught in traffic. When the queue got moving and the roadworks cleared, I gunned the car, it accelerated quite briskly, but not like I would have expected.... We approached a roundabout and had to slow right down. Mean time, some boy racer in an Audi A3 was right up me chuff. I floored the car round the roundabout but it did not go like I wanted. Wifey then spotted the switch was in "E", flipped it, the car kicked down a few gears, and whammo! , I was looking at the headlining and the car was howling along. I glanced in the mirrors and wide boy was a speck in the distance!

So I guess my switch is fine then..... :wink:

Sorry Mark.

 

[mjtray]

Hold on guys...........I read somewhere that w124's start in first, not second as is the case on 190's.....the reason being that the W124 is a much heavier car.

This is certainly the case on my 1993 E280 and the same goes for my mates 1994 E320 CE.

Cheers

 

[Orlando 300E]

91' 124 300e
Pulls away in 2nd
After gearbox rebuild Still pulls away in 2nd
unless you force it!
cheers
O.