Xantia cuttting out/surging 2.0 Petrol Inj

Gregg1100 · Unread post by **Gregg1100** » 25 Nov 2004, 00:24

Hi Stuart,
The stepper that I had put on from a Citroen garage was £54, so I will get a pic of it this weekend, just to be sure we are all on the same page.
This item is black, fitted on with 2 torkz screws, with the engine breather pipes connected to it, also a terminal block of 4-5 wires coming from it.. The new bit really made engine revs surge so they fitted old one , and refunded cost of part.
Whatever happened to plugs and points.
Regards,
Greg

Stuart McB · Unread post by **Stuart McB** » 25 Nov 2004, 01:00

Have you tried the .......(dreaded) MAP sensor? Do a quick site search under MAP sensor, there's loads on the site about cleaning etc. Same site page as befor sell them.

Gregg1100 · Unread post by **Gregg1100** » 25 Nov 2004, 22:31

Hi All,
Map sensor. What is, and where is one of those when at home. Why do these cars need all this crap.? What does it do and why?. What does stepper motor do, and why. Why doesn`t someone make a manual that explains what parts do, and not just how to replace them?.
So many questions, too litle daylight at moment to do the jobs needed.
Regards,
Greg

Stempy · Unread post by **Stempy** » 25 Nov 2004, 23:51

MAP = Manifold Absolute Pressure, it measures the pressure in the manifold so the ecu knows how much air is flowing and thus calculate how much fuel to inject, and it works in conjuction with the other sensors such as throttle position, engine temperature, flywheel position etc. The Map sensor is on the inlet manifold.
The stepper motor controls the idle speed by varying air flow through the throttle body, so if the load on the engine changes, for instance, you switch on the aircon, then the idle speed can be maintained.
The reason they need all this crap is beacuse it gives a much more precise mixture than a caburettor and as such emmissions and economy can be greatly improved.

Gregg1100 · Unread post by **Gregg1100** » 28 Nov 2004, 17:06

Hi Stempy,
Thanks for the info.. I took stepper out again this morning. I got son to turn ignition on, and the centre part moved back into the stepper body, albeit very slowly. Tried to pull it back out, and it was very hard to pull it back out(with ign off or on) I threw a bucketful of WD40 at it, and it made it a little easier to pull out or push in by hand, but not a nice easy movement.
Can you tell me if they are an easy sliding fit, in or out, so I can judge whether mine wants binning. I am positive this motor is the culprit.Looks like more drinking vouchers are not going to intended place. [:(!] [:(]
Regards
Greg

Stempy · Unread post by **Stempy** » 29 Nov 2004, 11:21

It's not the easiest of things to get out because of the way it works. It's like a worm gear type arrangement and so twists as it moves. It will come right out with enough twiddling.

Stuart McB · Unread post by **Stuart McB** » 29 Nov 2004, 15:29

Mate put the WD40 away. When you clean with this it leaves a little bit of sludge in the barrel of the stepper. Try using carb cleaner as it drys when done cleaning. Then to lubricate use a bit of silicone spray (WD40 do one) this will clean it far better than WD40 wil ever do. As for movement when the power is off the valve should move quite freely but not loose.

Gregg1100 · Unread post by **Gregg1100** » 29 Nov 2004, 22:01

Hi Stempy,
Once again i strpped the stepper pit of car, libricated it, put it back together, used the car this morning---perfect-----coming home tonight in traffic, the engine was getting up to normal temp,and the surging and jerking started again. Ot top of that, I found my n/s front carpets wet, wondered why car was misting up all the time. My Volvo is looking more and more a better bet, that has a 1.7 injection engine with half the crap this Citro has. My interest in these cars are waining fast. Still got a cluch pedal thingy to do on my Zant TD. What a brain dead idea that was too . I have had my daily whinge, so feel only a tad better now.
Seriously, thanks for your ideas, Stempy, much appreciated,
Regards
Greg

Stempy · Unread post by **Stempy** » 30 Nov 2004, 01:15

Shame. Such good cars when everythings working(rare). Sorry to hear you have a blown matrix, big job. Think I'd prefer the CB125 to the Volvo though!

Gregg1100 · Unread post by **Gregg1100** » 30 Nov 2004, 02:00

Hi,
Water level in rad hasn`t gone down, but that plastic cover over windscreen wipers is cracking. Apparently water can get in there.
Greg

Gregg1100 · Unread post by **Gregg1100** » 05 Dec 2004, 20:39

Hi All,
Going to push the boat out and buy an idle stepper motor. The original is virtually seized up, no amount of carb cleaner/WD40 will make it slide in and out reasonably easy. I may order a potentiometer for throttle while I am at it. Only £100 all in----only 50+ pints of lost beer (swine of a car).
Does anyone make a manual for the 16v Citroen Xantia---Haynes finest can`t stretch to that.
Thanks for all your help
Greg
Will be selling this VSX when going correctly---will go back to a diesel---less hassle.