erratic acceleration

charlie victor · Post by **charlie victor** » 03 Sep 2004, 05:39

my xantia 2.1td 12v 1998 r is behaving rather peculiar
it accelerates by itself at all sorts of different revs its even touched 5000 revs the acceleration normally lasts a few seconds
can any one help please

uhn113x · Post by **uhn113x** » 03 Sep 2004, 12:20

Hi Charlie
I assume last sentence is a question, so here goes:
If it is nothing simple like the throttle cable sticking, the most likely thing is that the engine is running on oil/oil mist that is somehow getting into the induction system. Does it smoke at all? Not familiar with the layout on your car, but likely causes are something wrong with the breather system or turbo seals failed.
BTW, if your engine will do 50,000 RPM you should stick some wings on your car!! [}:)][:D]

NiSk · Post by **NiSk** » 03 Sep 2004, 12:56

The '98 TD12 is a fly-by-wire design, i.e. no throttle cable. I'd guess that there's a loose connection somewhere in the electrics. Means you have to get it diagnozed to get an idea about where to look.
//NiSk

Stuart McB · Post by **Stuart McB** » 03 Sep 2004, 16:50

Check all plugs on the throttle housing. Check and clean MAP sensor and the idel stepper motor if fitted. Also do a site search under 'rev's stopping up'
Hope this helps

charlie victor · Post by **charlie victor** » 04 Sep 2004, 12:08

thanks everyone ,
i will let u know how i get on
at the moment still looking for the throttle housing , map sensor, idle stepper motor and me haynes manual

charlie victor · Post by **charlie victor** » 05 Sep 2004, 12:39

this problem seems to have disapeared for the last couple of days.
but does anyone know why the rev's stay where itis for a second or two before returning when i accellerate?

Kered · Post by **Kered** » 05 Sep 2004, 14:55

Hi CV
This problem has been aired several times on this forum. Read the contents of the link:
http://www.andyspares.com/discussionfor ... IC_ID=7568
If you don't find the answer here do a search for Hunting.
Derek

charlie victor · Post by **charlie victor** » 07 Sep 2004, 03:10

oops its come back again ! [:(]
i think it's just me , trying to make myself believe its not there[:(]

charlie victor · Post by **charlie victor** » 08 Sep 2004, 07:52

thanks everyone
took it to a diesel specialist who told me that he'd cleaned all the electrical connections .(i guess he means the sensors connections )
so far drove it 20 miles problem seems to have gone

charlie victor · Post by **charlie victor** » 11 Sep 2004, 12:46

hi everyone
good job he did not charge me for that. cause
guess what it's back yep that same old erratic aceleration.
anyway more to the point i think i have cured it myself
the airfilter pipe was split open , so i wrapped some tape around it and so far so good
that helped , but the problem was still there the latest i have fitted what dave t mentions inhis post (PART NO.1338 78 STOCK SENSOR ENGINE) ,its been six days since and no sign of the problem

Stuart McB · Post by **Stuart McB** » 11 Sep 2004, 23:37

Thats got too help. Espescialy on the induction side of things.

alan s · Post by **alan s** » 19 Oct 2004, 05:48

Can I throw a bit of a wobbly in here for consideration?
A couple of years back we had a series of people having diesels revving uncontrollably in some cases until the engines self destructed. This was caused by a variety of things in come cases oil vapour from the crankcase and in others from dirty or parially blocked air cleaners.
I'd suggest checking this aspect out before it goes too far as in some cases it started something like this and eventually just revved itself to bits when the engine was turned off at the key one day.
May not be the problem, but it's one that shouldn't be overlooked.
Alan S

uhn113x · Post by **uhn113x** » 19 Oct 2004, 12:57

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by alans

Can I throw a bit of a wobbly in here for consideration?
A couple of years back we had a series of people having diesels revving uncontrollably in some cases until the engines self destructed. This was caused by a variety of things in come cases oil vapour from the crankcase and in others from dirty or parially blocked air cleaners.
I'd suggest checking this aspect out before it goes too far as in some cases it started something like this and eventually just revved itself to bits when the engine was turned off at the key one day.
May not be the problem, but it's one that shouldn't be overlooked.
Alan S
<hr height="1" noshade id="quote"></blockquote id="quote">
Yep, agreed, Alan. I did mention it above in post 3/9/04 [:)]

alan s · Post by **alan s** » 19 Oct 2004, 14:23

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by uhn113x

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by alans

Can I throw a bit of a wobbly in here for consideration?
A couple of years back we had a series of people having diesels revving uncontrollably in some cases until the engines self destructed. This was caused by a variety of things in come cases oil vapour from the crankcase and in others from dirty or parially blocked air cleaners.
I'd suggest checking this aspect out before it goes too far as in some cases it started something like this and eventually just revved itself to bits when the engine was turned off at the key one day.
May not be the problem, but it's one that shouldn't be overlooked.
Alan S
<hr height="1" noshade id="quote"></blockquote id="quote">
Yep, agreed, Alan. I did mention it above in post 3/9/04 [:)]
<hr height="1" noshade id="quote"></blockquote id="quote">
Saw that as I posted it, but I'm in the middle of a greasy job that don't bear thinking about as well as in the middle of a pretty rough electrical storm taking the power down every few minutes so I didn't have the heart to play around wih it.
Possibly wouldn't do any harm to bring it to the surface again though seeing as it can lead to catastophic results.
Alan S

charlie victor · Post by **charlie victor** » 13 Dec 2004, 04:38

Hi everyone
just to let u know that (PART NO.1338 78 STOCK SENSOR ENGINE) was the cure . Been running fine after replacing this..for best part of 2 months.
thanks everyone