Stepper motor

Gregg1100 · Post by **Gregg1100** » 19 Dec 2004, 22:19

Hi All,
I fitted my new stepper motor today. Disconnected battery, fitted motor, re-connected battery. <b>Still the same</b>, jerking and although revs aren`t so high, it takes a bit of time to return to tickover.Damn . It`s the jerking that is sucking me off. Feels like the ignition is being turned off and on very quickly. Not making for a comfortable ride. Will take it off the road after Xmas and get what I can for it. Have had enough of messing around with the thing.
Regards,
Greg

Stempy · Post by **Stempy** » 20 Dec 2004, 02:29

Is it a manual or auto box?

PeterMann · Post by **PeterMann** » 20 Dec 2004, 19:13

Sounds like my Xantia may have the same problem as yours ; sometimes when I come off the throttle it bounces with surges of acceleration.
I reckon that my stepper motor is OK, and would be interested to hear what you discovered when you have a solution.[8)] nicolewis@optusnet.com.au

Stuart McB · Post by **Stuart McB** » 20 Dec 2004, 21:03

This could be sign of throttle potentionometer or the dreaded MAP sensor. The sensor will tell the ECU how much loads is on it and the throttle will tell the ECU how far open the butterfly valve is and so ajust then engine accordingly. Try removing thr throttle potentionometer and regreasing it, also give the throttle housing a good clean with carb cleaner. May help.

Gregg1100 · Post by **Gregg1100** » 20 Dec 2004, 22:50

Hi,
The car is a manual 16v. The exhaust note heard from back of car is like an uneven running, missing a few beats type of sound. Once revved up, car goes quite well. Going now to look at GSF to check prices of potentiometer. I have to get this car going right, just to sell it.
Thanks for answers so far,
Greg

Stuart McB · Post by **Stuart McB** » 21 Dec 2004, 01:31

If you can get the part number off the unit as fitted to the car you can save some money buy calling auto teknik,
www.autoteknik.co.uk
Over night delivery and ££'s cheaper than a main agent.

SGould · Post by **SGould** » 21 Dec 2004, 19:30

Hi, my stepper needs changing but the problem is not jerking. On some occasions, particularly when starting from warm - say after 1 or 2 hours being off- the revs will die away when stopping at a junction or lights. This has been happening for years (1.8 16v manual) but it is slowly getting worse. However, after a short while, particularly when you have done a few miles without stopping, all is fine. The Xantia has only done 62K.
The garage said that the stepper needs changing. I hope that the problem is not one which will involve the need to get rid of the car!!
I have the same exhaust note but this has been the same as when we first got the car with 40k on the clock (and when we did not have a problem with the revs)

Gregg1100 · Post by **Gregg1100** » 22 Dec 2004, 22:14

Hi,
Took of battery lead Tuesday night, done the trottle push(twice) and reconnected lead. Still the same. Will order a potentiometer tonight. My Volvo has an injection engine, with very little of all this junk. Looking more like it`s coming back on road, while I get this shed of a car working properly. It will be for sale after. Very clean VSX 2 ltr 16v 1997. I will sell my 94 TD Xantia as well. Please shoot me if I ever buy a petrol car again.
Thanks for your interest,
Greg
Ps. Will leave battery lead off all one night, just to check if ECU clears.

Gregg1100 · Post by **Gregg1100** » 28 Dec 2004, 01:15

Hi,
The latest to my tale of woe.
I sent for a new potentiomter from GSF. It duly arrived Xmas eve morning. I went outside today to fit it-----wrong bloody one. Those donks at Citroen have mixed up Marelli parts with Bosch. The system is Marelli, stepper motor is Marelli, <b>potentiometer is Bosch.</b> Ho Ho Ho. Well done Citroen. You have excelled yourselves.
Another phone call, another wait.. I took pic of the removed PTMTER, so they can identify right part.
Will keep you posted
Greg

alan s · Post by **alan s** » 28 Dec 2004, 04:20

Just popped in on this one and to me it sounds as though you could be having air leaking on the intake side of the engine.
I might be wrong but you've definitely got the symptoms there. Has anyone bothered to go looking for split hoses and air leaks?? Could save you a lot of aggro as well as a fair amount of cash..
Alan S

David Goddard · Post by **David Goddard** » 28 Dec 2004, 13:45

Regular missfire? Sounds more like the ignition system (plug, coil, leads, ECU). I think the stepper motor only operates at tick over. A fault may make the tickover erratic but won't create a reguar misfire. Faulty throttle pot. is usually only apparent at a certain position of the throttle. The bad pot. then sends a low voltage back to the ECU which then turns down the injectors. Result bad running and a hesitation. Once through that band, it will possibly be fine.

Gregg1100 · Post by **Gregg1100** » 28 Dec 2004, 22:46

Hi All,
Thanks for the new ideas---will look at them tomorrow if back holds out---pulled it last Thursday at Okehampton, unstrapping the contents of a trailer( 45 footer). Will get new plugs Saturday.
This car had a replacement head 4000 miles before I bought it, cam belt went, so did head.
On another lighter note, I started up my TD Xantia today---2 dollops of heater plugs and away she went---just got to put clutch pedal back in---dreaded clip--- and do a top speedo cable change.
Thanks for new areas of isnspection lol
Greg