Technical punto automatic slipping ( gearbox position sensor )

[audiohabit]

punto automatic slipping fix ? ( gearbox position sensor )

Hi all this may help some people with slipping gearbox and maybe someone can help me too
Fist of I have an automatic punto that was slipping a couple of years ago and to fix it I just move the gearbox position sensor on the shaft going into the box under the battery tray and it then worked fine

I now have another one with exactly the same fault , it works fine in reverse like the first one so I tried adjusting the sensor and depending which way you adjust it it does different things , ie won't start or will drive ok but then jump back to slipping after a few seconds

So I got another sensor and its definitely better but still goes back to slipping , im 100% sure its something to do with the position sensor and setting it up right as it fixed the last car and you can see its making a difference depending on it position

So is there a correct way to set this sensor up ?

Many thanks

And people with slipping gearbox just try undoing the two 8mm bolts on the sensor and moving it left or right as this worked for me , no more gearbox fail warnings lights and drove perfect ,

Any help would be great thanks

 

[varesecrazy]

Hi,

by your description of an Auto,
I'm guessing it not a modern Punto , ( as they are semi-auto's..= a manual g-box..)

Charlie

 

[audiohabit]

Hi yes its a 2003 punto 1.2 speedgear cvt gearbox ,

 

[audiohabit]

This is the sensor in question

 

[audiohabit]

As you can see there is a little room for adjustment left or right , and the difference it makes is unbelievable if you go all one way it wint even start

 

[audiohabit]

Anybody know the correct name for this sensor

 

[audiohabit]

Anybody know please im stuck

 

[varesecrazy]

Anybody know the correct name for this sensor

thanks for the pic..,

we did have a resident expert in homeward..,
but not on here lately

does this help;
http://eper.fiatforum.com/eper/navi...3&WINDOW_ID=1&SGRP_COD=22&SGS_COD=0&DRW_NUM=1

Charlie - Oxford

 

[audiohabit]

Hi thanks for the reply ,

Ive just gone through all 69 pages of the auto data and still cant see this sensor, in fact there don't seem to be any sensors in it, even when I went to electrical components ,

This really is puzzling me now, and im guessing, but I think there may be a correct way to set it up

 

[audiohabit]

The sensor is there in the complete auto gearbox drawing, but its not in any of the sub drawings

 

[audiohabit]

Right I have found out what its called , its the transmission range sensor or pnp switch , the replacement I got was from a breakers yard so there is a chance that it had the same fault, so do I get a new one or am I going down the wrong path ? Im almost certain its something to do with this sensor as the last car was exactly the same, just slipping when going faward but still driving , and the fact it changes depending on position

 

[audiohabit]

Can anyone help please im losing my battle with this car ,

 

[varesecrazy]

Re: punto automatic slipping fix ? ( gearbox position sensor )

any use..??

https://www.fiatforum.com/tech-talk/288074-punto-speedgear-cvt-gearbox-selector-issue-help.html

 

[audiohabit]

Yeah ive read that thread and its the same sensor , im just wondering if there is a special way of setting this sensor up , there is about 5mm of adjustments in the sensor and i have tried it in virtually all positions and everyone has a different effect on the gearbox , but when it is all the way to the left it runs ok for a couple of minutes and then appears to jump back into slipping that is what is making me think it has to be the sensor as if you set it off in the middle it just slips immediately but i am going to try and get a nother sensor tomorrow and see if that works

 

[Ziggy122]

Wait - isn't it a manual box with a robot on the job?
Could be the clutch is generally worn out?

Ziggy

 

[audiohabit]

Hi there no its the cvt speedgear box , but that is exactly what it feels like as if the clutch is slipping , the one I had a couple of years ago I would never of imagined it was down to a sensor to fix it, you would be 100 percent sure there was internal damage to the box, bo no just moving the transmission range sensor fixed it , the thing is I bet there is so many people that have had this problem and have had their gearboxes taken out or replaced when alls they needed to do was adjust the sensor , there must be someone that knows about this ???

 

[audiohabit]

Was this gearbox used in any other cars or different makes of cars ???

 

[Twotoncarman]

I would imagine the sensor is used to select the point at which the drive engages or disengages, an analogy would be a centrifugal clutch, or, a torque converter take up point.
If moving it throught the full range still leaves slippage, and, the sensor is ok, then I would suspect internal failure of the gearbox.
Have you tried a full fluid change on the box ?

 

[a1ant]

Hi,

The sensor in your picture of the CVT box is the multi-function inhibitor switch.

Its acts as an old fashioned inhibitor switch (preventing the car from starting when not in P) and also a position sensor which supplies the gearbox ECU with information on weather the car is in D, P, N, R etc etc.

Depending on the signal from the switch, the gearbox ecu has different operating strategies.

It can also have an effect on the solenoid valve that controls the amount of "lock up" of the torque converter. (amount of slip allowed etc)

When the shifter is in D what does the dash display?
When the shifter is in R what does the dash display and do the reverse lights activate?
When in sequential mode, does thee car drive differently?

As has already been mentioned, the quantity and quality of the CVT fluid is also essential. When was it last changed and level checked?

Alan

 

[audiohabit]

Thanks all the dash letters work ok , reverse lights work ok, oil level and quality is fine, I have ordered a new sensor today so ill find out how I get in when it arrives and let you guys know

And its the same in all faward gears but works perfectly in reverse , it also takes about 4/5 seconds to engage into any faward gear but its instant in reverse

I read today the way to set this sensor up is put the stick in N and adjust the sensor until the reverse lights come on , then tighten up the two bolts , this was an generic way to do it with all positions census so i presume it's the same on the punto, I try it with the sensor I have and yes the reverse light did come on when I moved it ,

But yeah ill check the new sensor and hope for the best