Noisy Xantia 1996 TD
Moderator: RichardW
Noisy Xantia 1996 TD
My son bought this car a few months ago and has done about 5000 miles in it, I did a service on it when he bought it oil and all filters changed. He came up from Cornwall to see me today 350 miles car gave him no problems, checked oil and water before setting off all OK and are still OK. When he stopped at my house engine sounded fine, about 3 hours later he started it and the engine was making knocking noises when ticking over and up to about 1200revs and then goes smooth again, I thought it might be the aux belt or pulleys but it is not, it does appear to be from the area of the pump. If it was a petrol engine I would think it was a big end, it is that sort of noise. Could it be one of the injectors, can anyone suggest any possible causes of this noise, my son will be travelling back to Cornwall on Sunday and I would like to sort this noise out first.
Hmmm...
I'd be a bit suspeciuos on the HP pump - known to sometimes emit sounds like a worn engine.
The problem may however be one of those innocent intermittent air problems - if a problem exists on the pump's suction side.
The HP pump's feed hose should be the first victim of suspicios checks - especially the hose clamps tightness (or lack of such) on pump & reservoir studs. Any surface cracks on the hose rubber is also a telltale.
Dirty/filthy reservoir filters also known to strangle the pump.
I'd be a bit suspeciuos on the HP pump - known to sometimes emit sounds like a worn engine.
The problem may however be one of those innocent intermittent air problems - if a problem exists on the pump's suction side.
The HP pump's feed hose should be the first victim of suspicios checks - especially the hose clamps tightness (or lack of such) on pump & reservoir studs. Any surface cracks on the hose rubber is also a telltale.
Dirty/filthy reservoir filters also known to strangle the pump.
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Dave Burns
- Posts: 1915
- Joined: 14 May 2001, 05:30
- Location: United Kingdom
- My Cars:
- x 2
Does the engine rock back and forth any more than usual during this racket at tickover.
Is it an ECU model, if it is its located rearward of offside headlight in a big plastic box.
It sounds like a timing error, the knock could be a pronounced diesel knock rather than mechanical, build the engine revs slowly, to see if it goes quit all of a sudden and at the same speed each time.
This fault makes a loud metalic like knock at every firing stroke so if it only seems to be doing it once every revolution I would look elsewhere.
Doubt it will be an injector but you never know, I once had one stick on a merc van but it knocked at all engine speeds, if you think it could be you could crack their unions one at a time, if the noise stops on one of them then it would certainly look like an injector fault.
Doubt its a big end, they don't go quiet once they are goosed, they get noisier with increasing engine speed, the only possible exception being during periods of abnormally low oil pressure.
Dave
Is it an ECU model, if it is its located rearward of offside headlight in a big plastic box.
It sounds like a timing error, the knock could be a pronounced diesel knock rather than mechanical, build the engine revs slowly, to see if it goes quit all of a sudden and at the same speed each time.
This fault makes a loud metalic like knock at every firing stroke so if it only seems to be doing it once every revolution I would look elsewhere.
Doubt it will be an injector but you never know, I once had one stick on a merc van but it knocked at all engine speeds, if you think it could be you could crack their unions one at a time, if the noise stops on one of them then it would certainly look like an injector fault.
Doubt its a big end, they don't go quiet once they are goosed, they get noisier with increasing engine speed, the only possible exception being during periods of abnormally low oil pressure.
Dave
Hello Anders, it is strange that you should refer to the filters and pump, as I suspect the filters are clogged as the stop light takes about 10 seconds to go out when first started in the morning, and I intend to clean the filters and replace the LHM with Hydroflush in the morning.
Hello Dave,the engine does not rock about any more than usual, the pump is mechanical no ECU, the noise does always disappear at the same time when the revs are increased the engine is then quiet and smooth. I have heard a diesel knock due to a timing error and the noise on my son's car is similar to that noise except it disappears at about 1200 revs, what would cause the timing to alter other than a slipped belt. The engine does not smoke and there is no loss of power.
Hello Dave,the engine does not rock about any more than usual, the pump is mechanical no ECU, the noise does always disappear at the same time when the revs are increased the engine is then quiet and smooth. I have heard a diesel knock due to a timing error and the noise on my son's car is similar to that noise except it disappears at about 1200 revs, what would cause the timing to alter other than a slipped belt. The engine does not smoke and there is no loss of power.
Just been out to listen to this noise again and it does seem to be coming from the pump, I think this pump is a 6+2, If I touch a metal pipe on the side of the pump radiator side I can feel this vibration quite severely and if I put pressure on this pipe (push it) the noise stops, maybe the pump is loose I will check tomorrow although it does not feel loose.
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Dave Burns
- Posts: 1915
- Joined: 14 May 2001, 05:30
- Location: United Kingdom
- My Cars:
- x 2
All the 1.9td's have mechanical pumps but around that year they were also given an ECU which takes control of injection timing advance, whereas it was previousely purely a function of engine speed acting on components inside the pump.
In the purely mechanical version timing advance is brought about by incresing fuel pressure from the lift pump withinn the pump body, acting on a transverse piston that turns the roller ring.
In the ECU version, timing is still via the roller ring, and its operating piston to supply the turning force, but now the internal fuel pressure is controlled by a solenoid valve that is in turn controlled by the ECU, software telling it what the timing value should be and it checking this via the injector lift sensor and TDC sensor, then if necessary altering the pressure within the pump body via the solenoid valve.
If the timing were out due to a belt/pulley error, any resultant noise would almost certainly not go away at any rpm.
10 seconds to put the hydraulic warning light out is more likely to point to a reduced gas pressure in the accumulator sphere rather than blocked fitlers, which are only strainers after all.
Dave
In the purely mechanical version timing advance is brought about by incresing fuel pressure from the lift pump withinn the pump body, acting on a transverse piston that turns the roller ring.
In the ECU version, timing is still via the roller ring, and its operating piston to supply the turning force, but now the internal fuel pressure is controlled by a solenoid valve that is in turn controlled by the ECU, software telling it what the timing value should be and it checking this via the injector lift sensor and TDC sensor, then if necessary altering the pressure within the pump body via the solenoid valve.
If the timing were out due to a belt/pulley error, any resultant noise would almost certainly not go away at any rpm.
10 seconds to put the hydraulic warning light out is more likely to point to a reduced gas pressure in the accumulator sphere rather than blocked fitlers, which are only strainers after all.
Dave
I relaced the accumulator sphere on my Xantia to lengthen the time between clicks which it did from 10secs to over 2 mins. but the light still took about 5 secs to go out. I cleaned the filters which were very dirty and put in the Hydroflush and that has had the effect of putting the light out very quickly almost as quick as when the engine is warm. Anyway the fault on my sons car does now seem to be related to the pump, I will know more tomorrow I hope when I examine the pump for tightness etc.
Update on this, I started the car on Saturday morning 27/09/03, the pressure light took about 12 secs. to go out. I cleaned the filters and changed the fluid to Hydroflush. I started the car on Sunday morning 28/09/03 and the light went out at about 5 secs. My son took the car home on Sunday back to Cornwall, he rang me yesterday and he said the light now goes out very quickly, he is not timing it but he recons less than 5 secs, car has now done 800 miles since change. I had exactly the same experience with my Xantia when I cleaned the filters and put Hydroflush in that. So that by doing this it does seem to have a positive effect on the oil light.