<font face="Comic Sans MS"></font id="Comic Sans MS">Hi Guys,
I removed the MAP sensor Sat morning and cleaned it out. On Sunday, I refitted the sensor, along with new Potentiometer. I found that the breather system from cyl. head was blocked up, so cleaned all that out. When all back together again, , on entering my code to start, I pushed throttle to floor twice, then started car. It started great, but only about 30 secs later , the same uneven running started again. and revs still slow to die down. The chuffing noise seems to have stopped, so probably blocked breather was the cause of that.
So, I have changed potentiometer, stepper motor, checked all round for air leaks, cleaned out breather system, cleaned map sensor, removed and refitted spark plugs to see if any were fouled up. Not. The jerking still there, but not so much. I have had enough of this now, but can`t afford to take it to a garage for them to build up a bill for more than cars worth. Anyone want to buy a 16v, 1997 (P). Just taxed the pig too.
Thanks to all you guys that have helped me on this problem,
Regards,
Greg
PS. Main Citroen dealer bloke reckons that 16v`s don`t like NGK or Bosch spark plugs. He reckoned that Equeum were the bees knees, but was probaly on a commission.<font color="blue"></font id="blue">
Not Yet Fixed
Moderator: RichardW
-
Stuart McB
- Posts: 1635
- Joined: 03 Oct 2003, 00:50
- Location: United Kingdom
- My Cars:
- x 1
Greg for what it's worth I had no end of this kind of trouble with my Xsara VTR. The only plugs that seemed to be any good were Bosch super 4's. The running at tick over is far smoother with these plugs that with any of the orther names you mentioned. You may find that the stepper motor is kapput. This too can be affected by oil residue build up and may also need a clean. The slow rev return certainly sound like a dicky idel motor / valve. Yours should be a small black magnet marelli thing on the inlet manifold with a multi plu on it. Go on give it a clean what you got to loose.
try www.autoteknik.co.uk for a cheap OE part. [:D]
try www.autoteknik.co.uk for a cheap OE part. [:D]
<font color="blue"><font size="2"><font face="Comic Sans MS">Hi Stuart,
Have ordered some plugs. The stepper motor is new, as is potentiometer. I cleaned stepper motor out Sunday because crankcase breather/pipes were blocked, allowing dirt to get into it..
Is there a difference between an 1.8 16v head and a 2.0 litre 16v cylinder head. A citroen agent I first took car to, seemed to think a 1.8 head had been fitted, and coil pack modified to make it run. ( The car had a new head on it, due to belt snapping, this was done not long before yours truly bought car ). Wondered why I got it so cheap.
Regards
Greg</font id="Comic Sans MS"></font id="size2"></font id="blue">
Have ordered some plugs. The stepper motor is new, as is potentiometer. I cleaned stepper motor out Sunday because crankcase breather/pipes were blocked, allowing dirt to get into it..
Is there a difference between an 1.8 16v head and a 2.0 litre 16v cylinder head. A citroen agent I first took car to, seemed to think a 1.8 head had been fitted, and coil pack modified to make it run. ( The car had a new head on it, due to belt snapping, this was done not long before yours truly bought car ). Wondered why I got it so cheap.
Regards
Greg</font id="Comic Sans MS"></font id="size2"></font id="blue">
I can't speak for the 16V Xantia, but I can tell you for sure that a CX2400 and a CX2200 head is definitely not interchangeable.
When I say that, I don't mean that you can't fit one to the other, they will physically fit, but several little variances appear as you try to refit it, such as location of studs for the exhaust manifold and matching ports so much so that the manifolds had to be also changed. At the end of the job, even after a full on reco job was done on the head, it ran worse than the old clapped out head, so the moral of the story is to firstly check that you do have a compatable head.
Only a dealer could suggest the breed of plugs making such a difference; no way in the World, in fact I've just ditched a set of Equyem plugs and replaced them with a set of Bosch Super 4s on a TZi and didn't notice a scrap of difference and previously I have done the opposite on my 16V. Gone from Bosch to Equyem and no noticeable difference apart from a bit more even running due to plugs being new, not due to the brand.
If there's any distinguishing marks on the head it may be worth talking to a parts dealer or if you know an experienced wrecker, he may be able to tell you the difference.
Alan S
When I say that, I don't mean that you can't fit one to the other, they will physically fit, but several little variances appear as you try to refit it, such as location of studs for the exhaust manifold and matching ports so much so that the manifolds had to be also changed. At the end of the job, even after a full on reco job was done on the head, it ran worse than the old clapped out head, so the moral of the story is to firstly check that you do have a compatable head.
Only a dealer could suggest the breed of plugs making such a difference; no way in the World, in fact I've just ditched a set of Equyem plugs and replaced them with a set of Bosch Super 4s on a TZi and didn't notice a scrap of difference and previously I have done the opposite on my 16V. Gone from Bosch to Equyem and no noticeable difference apart from a bit more even running due to plugs being new, not due to the brand.
If there's any distinguishing marks on the head it may be worth talking to a parts dealer or if you know an experienced wrecker, he may be able to tell you the difference.
Alan S
<font color="blue"><font size="2"><font face="Comic Sans MS">Hi All,
I changed the plugs today---still running like a pig. I had a good look round engine, looking for a Map Sensor, with a vacuum pipe attached. Zero. The only vacuum pipe on this engine is attached to fuel rail and goes to an outlet on underside of inlet manifold. The only other vaccy type pipe goes from throttle housing to the charcoal filter under wing-which seems to chuff as flaps move.
The engine runs as if there is a vaccy pipe off, the mixture being upped to counteract the extra air available.There is a black box thing under inlet manifold about 5 inches long, with nothing going to it. What is that ?. If I block off the vaccy pipe to charcoal filter, will it do any damage to run car ?. Never had these filters years ago.
I think Alan S was right about air leaks, but can`t find any.
Greg</font id="Comic Sans MS"></font id="size2"></font id="blue">
I changed the plugs today---still running like a pig. I had a good look round engine, looking for a Map Sensor, with a vacuum pipe attached. Zero. The only vacuum pipe on this engine is attached to fuel rail and goes to an outlet on underside of inlet manifold. The only other vaccy type pipe goes from throttle housing to the charcoal filter under wing-which seems to chuff as flaps move.
The engine runs as if there is a vaccy pipe off, the mixture being upped to counteract the extra air available.There is a black box thing under inlet manifold about 5 inches long, with nothing going to it. What is that ?. If I block off the vaccy pipe to charcoal filter, will it do any damage to run car ?. Never had these filters years ago.
I think Alan S was right about air leaks, but can`t find any.
Greg</font id="Comic Sans MS"></font id="size2"></font id="blue">
-
Richard Gallagher
- Posts: 803
- Joined: 31 Oct 2001, 02:36
- Location: South Bucks
- My Cars:
<font color="blue"><font size="2"><font face="Comic Sans MS">Hi Richard,
Will have a look tomorrow afternoon. Still can`t find any vaccy pipes extra to the one mentioned above.. The head ia a replacement after a belt snapped before I had car, not fitted by a Citroen garage, just wondering if something has been left off. That is what it feels like---an air leak, which would probably upset everything else, but it is finding it. Nearly got my Volvo ready for the road----will be simpler to maintain, lol.
Thanks,
Greg</font id="Comic Sans MS"></font id="size2"></font id="blue">
Will have a look tomorrow afternoon. Still can`t find any vaccy pipes extra to the one mentioned above.. The head ia a replacement after a belt snapped before I had car, not fitted by a Citroen garage, just wondering if something has been left off. That is what it feels like---an air leak, which would probably upset everything else, but it is finding it. Nearly got my Volvo ready for the road----will be simpler to maintain, lol.
Thanks,
Greg</font id="Comic Sans MS"></font id="size2"></font id="blue">
Just a thought but Im no expert.
I had an 8v 2ltr xantia that I put in a so called cit specialist for a service, when I picked it up I got 50 yds down the road and it started stalling. I took it back in the garage and the guy put his diagnostic tester on ecu and it showed a sensor failiure. He reprogram the ecu or something and it enabled me to drive around ok. I had a look for a sensor and couldnt find it anywhere so had to give in and put it in the local cit dealer. they replaced the sensor which was faulty but also noticed that it had incorrect plugs which were changed during the service. One thing I forgot to mention was that when it was with the specialist for the service I told him that the brakes were making a terrible grinding noise, he said he could find nothing wrong with them. A couple of days later I couldn bear this noise so took a look myself to find the pads worn to the metal. So loosing all faith in cit specialsts in my area I do the work myself. I took the incorrect plugs and worn pads to the specialist and demanded a refund on the parts.
So what I was saying was maybe an idea to have a diagnostic test done on it.
Haydn
I had an 8v 2ltr xantia that I put in a so called cit specialist for a service, when I picked it up I got 50 yds down the road and it started stalling. I took it back in the garage and the guy put his diagnostic tester on ecu and it showed a sensor failiure. He reprogram the ecu or something and it enabled me to drive around ok. I had a look for a sensor and couldnt find it anywhere so had to give in and put it in the local cit dealer. they replaced the sensor which was faulty but also noticed that it had incorrect plugs which were changed during the service. One thing I forgot to mention was that when it was with the specialist for the service I told him that the brakes were making a terrible grinding noise, he said he could find nothing wrong with them. A couple of days later I couldn bear this noise so took a look myself to find the pads worn to the metal. So loosing all faith in cit specialsts in my area I do the work myself. I took the incorrect plugs and worn pads to the specialist and demanded a refund on the parts.
So what I was saying was maybe an idea to have a diagnostic test done on it.
Haydn
<font color="blue"><font size="2"><font face="Comic Sans MS">Hi All,
I had the throttle assembly off again today, to make it easier to see where map sensor is. Result. NIL. There is nothing which resembles the pic of a map sensor that Anders found for another guy on this forum. There is ONLY 1 vacuum pipe on the engine, going from fuel regulator (part of fuel rail ), to the underside of inlet manifold near to throttle assembly. There is a blanked off stub of pipe next to where the vacuum pipe enters manifold.
What is that black container thing that sits under the inlet manifold. Is it a plenum chamber or something?.
The only other pipe that looks like a vacuum pipe goes from throttle assembly goes to the charcoal filter in n/s/f wing
So heaven only knows what the heck is going on with this car.
All there is under inlet manifold is a thing screwed in, which looks like an oil pressure switch. I have had that out and cleaned it with carb spray.
Apparently the oxygen sensor can give jerky,uneven running too, if it is naff.
The local Cit main dealer wants £60 just to connect car to tester. I really don`t want to go there as I wouldn`t take a wheelbarrow with a squeaky front axle to them.
All breather pipes clean, new stepper motor, new potentiometer, throttle assembly cleaned out, invisible MAP sensor, not much left.
I can`t sell car until it runs right. ARE those Peter Russek manuals any good ?.
Getting really hacked off now
Greg [:(!] </font id="Comic Sans MS"></font id="size2"></font id="blue">
I had the throttle assembly off again today, to make it easier to see where map sensor is. Result. NIL. There is nothing which resembles the pic of a map sensor that Anders found for another guy on this forum. There is ONLY 1 vacuum pipe on the engine, going from fuel regulator (part of fuel rail ), to the underside of inlet manifold near to throttle assembly. There is a blanked off stub of pipe next to where the vacuum pipe enters manifold.
What is that black container thing that sits under the inlet manifold. Is it a plenum chamber or something?.
The only other pipe that looks like a vacuum pipe goes from throttle assembly goes to the charcoal filter in n/s/f wing
So heaven only knows what the heck is going on with this car.
All there is under inlet manifold is a thing screwed in, which looks like an oil pressure switch. I have had that out and cleaned it with carb spray.
Apparently the oxygen sensor can give jerky,uneven running too, if it is naff.
The local Cit main dealer wants £60 just to connect car to tester. I really don`t want to go there as I wouldn`t take a wheelbarrow with a squeaky front axle to them.
All breather pipes clean, new stepper motor, new potentiometer, throttle assembly cleaned out, invisible MAP sensor, not much left.
I can`t sell car until it runs right. ARE those Peter Russek manuals any good ?.
Getting really hacked off now
Greg [:(!] </font id="Comic Sans MS"></font id="size2"></font id="blue">
A specialist once told me that the engine electronics light stays on longer when you start the car if a fault is stored, and after seeing mine went off immediately, advised me to save the £10 he charged just for plugging it in and not bother.
He seemed like a really decent guy, he test drove my car for me, probably spent 20 mins entertaining me with my woes and didn't charge me a penny.
He is based near Romford Essex which would probably be worth a drive if you're close enough.
Also worth a try, have you tested the compressions?
Mind you, I don't know if he's any good with a Xantia Micro Machine!!!!!
He seemed like a really decent guy, he test drove my car for me, probably spent 20 mins entertaining me with my woes and didn't charge me a penny.
He is based near Romford Essex which would probably be worth a drive if you're close enough.
Also worth a try, have you tested the compressions?
Mind you, I don't know if he's any good with a Xantia Micro Machine!!!!!
I think the single small vacuum hose running from duct to throttle body is the clue.
As a couple of 1.8 owners here cant find an obviuos MAP unit, then it could be built into the intake duct - right where the small hose attaches.
The MAP sensor itself would not be bigger than 1/2 a matchbox as it only contains a pressure sensor element - no moving parts.
As a couple of 1.8 owners here cant find an obviuos MAP unit, then it could be built into the intake duct - right where the small hose attaches.
The MAP sensor itself would not be bigger than 1/2 a matchbox as it only contains a pressure sensor element - no moving parts.
<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Gregg1100</i>
<font color="blue">Hi Anders,
Would it then look like an oil pressure switch.
Thanks for your posting,
Greg</font id="blue">
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
I dont know as I've never seen those myself. But if it's got those 3 electric wires connected either end - then YES.
A MAP sensor must have 2 air connections. One is obviously in the manifold - AFTER the throttle flap. The other must be a reference which would be the air duct as this is clean air from the filter.
Then you have the sensor element wirings : 5V feed, earth, and signal.
<font color="blue">Hi Anders,
Would it then look like an oil pressure switch.
Thanks for your posting,
Greg</font id="blue">
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
I dont know as I've never seen those myself. But if it's got those 3 electric wires connected either end - then YES.
A MAP sensor must have 2 air connections. One is obviously in the manifold - AFTER the throttle flap. The other must be a reference which would be the air duct as this is clean air from the filter.
Then you have the sensor element wirings : 5V feed, earth, and signal.
-
Richard Gallagher
- Posts: 803
- Joined: 31 Oct 2001, 02:36
- Location: South Bucks
- My Cars:
Greg,
The MAP sensor on your car does not have a vacuum hose running to it because it bolts straight onto the bottom of the manifold.
As Dan states above, normally if a fault code is stored in the ECU then there is a slight delay in the 'K' (Diagnostic) light going out when starting the car.
If I'm not too far from you (Iver Bucks), I do have the magic machine to read fault codes.
The MAP sensor on your car does not have a vacuum hose running to it because it bolts straight onto the bottom of the manifold.
As Dan states above, normally if a fault code is stored in the ECU then there is a slight delay in the 'K' (Diagnostic) light going out when starting the car.
If I'm not too far from you (Iver Bucks), I do have the magic machine to read fault codes.