A few months ago I posted a problem with a smoking diesel engine.
Have changed oil/air/fuel filters and have had the glow plugs/injectors checked everything OK.
I seem to still have the same problem, but have a little more info, after starting (no problem) the engine does not smoke at all however hard I push in fact its probably the smoothest diesel I've driven, but after appx 3 minutes things go a bit pear shaped, on accelleration the engine either seems to be getting too much fuel therefore creating a ploom, not puff of black smoke and a severe lack of power until the turbo kicks in, getting only 28mpg (diesel), any pointers would be appreciated as I would prefer to drive the car for longer than 3 minutes as the nearest garage is 5 minutes away !
Too Much Fuel ?!!!
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Dave Burns
- Posts: 1915
- Joined: 14 May 2001, 05:30
- x 2
Presumably this is still the Xantia TDSX.
What year is it and is it a keypad version.
Whats the mileage.
How long have you had it and was this problem there to begin with or has it developed and if so over what period of time.
Black smoke or blue.
Any documented history of repairs giving possible links to the prob.
Dave
What year is it and is it a keypad version.
Whats the mileage.
How long have you had it and was this problem there to begin with or has it developed and if so over what period of time.
Black smoke or blue.
Any documented history of repairs giving possible links to the prob.
Dave
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Diablo
- Posts: 5
- Joined: 05 Nov 2002, 05:01
Dave,
It is indeed the Xantia TD LX, 1997 model c/w immobiliser keypad, mileage is only 63k verified miles and the smoke is black.
I have only had the car 3 months the symptons appeared about 3 weeks after purchase, I also followed a thread re ecu and presumably reset this by disconnecting battery negative lead ?
Regards
Vince
It is indeed the Xantia TD LX, 1997 model c/w immobiliser keypad, mileage is only 63k verified miles and the smoke is black.
I have only had the car 3 months the symptons appeared about 3 weeks after purchase, I also followed a thread re ecu and presumably reset this by disconnecting battery negative lead ?
Regards
Vince
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Dave Burns
- Posts: 1915
- Joined: 14 May 2001, 05:30
- x 2
I think it there are a few possible causes.
The EGR valve may not be functioning correctly, could be getting stuck open for some reason, as a test, disconect the wiring from the EGR electrovalve, preventing it opening at all.
The guide pin controling boost fuel in the pump could be sticking, disconect the rubber tube from the manifold pressure compensator on top of the fuel pump and plug the tube, this will prevent manifold pressure being sensed and prevent boost fueling.
The ECU can't influence the amount of fuel being injected, this is still a purely a mechanical function of the govenors, though I think it does now have a say in the timing of injection on these later but still quite basic pumps.
The diesel knock should sound quite sharp when cold, does it reduce to a more dull sound when the engine is hot.
Try the EGR valve first and with the engine from cold.
Dave
The EGR valve may not be functioning correctly, could be getting stuck open for some reason, as a test, disconect the wiring from the EGR electrovalve, preventing it opening at all.
The guide pin controling boost fuel in the pump could be sticking, disconect the rubber tube from the manifold pressure compensator on top of the fuel pump and plug the tube, this will prevent manifold pressure being sensed and prevent boost fueling.
The ECU can't influence the amount of fuel being injected, this is still a purely a mechanical function of the govenors, though I think it does now have a say in the timing of injection on these later but still quite basic pumps.
The diesel knock should sound quite sharp when cold, does it reduce to a more dull sound when the engine is hot.
Try the EGR valve first and with the engine from cold.
Dave
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Diablo
- Posts: 5
- Joined: 05 Nov 2002, 05:01
Dave,
After finally finding the circuit for the EGR (it had come loose and dropped behind the LHM reservoir I disconnected both circuits one blue/ one red, and plugged the end with large screw and insulation tape.
The reason I disconnected both, mainly because of my limited knowledge not colour blindness, amyway to the point, the car is like brand new ! not even the slightest of smoke even when trying to accelarate up a steep hill in 5th gear !!!.
At the moment it works fine and I,m sure it will improve mpg, but should I have disconnected both ??.
Many thanks again for your help
Vince
After finally finding the circuit for the EGR (it had come loose and dropped behind the LHM reservoir I disconnected both circuits one blue/ one red, and plugged the end with large screw and insulation tape.
The reason I disconnected both, mainly because of my limited knowledge not colour blindness, amyway to the point, the car is like brand new ! not even the slightest of smoke even when trying to accelarate up a steep hill in 5th gear !!!.
At the moment it works fine and I,m sure it will improve mpg, but should I have disconnected both ??.
Many thanks again for your help
Vince
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Dave Burns
- Posts: 1915
- Joined: 14 May 2001, 05:30
- x 2
Hi Vince, sorry should have said where to find the valves, IIRC the left electrovalve is for the EGR and the right hand one for the cold start fast idle adjustment.
Cold running fast idle is achieved by injection timing advancement, so make sure this is operating ok, disconect only one circuit or element at a time otherwise fault finding becomes a hit and miss affair.
Dave
Cold running fast idle is achieved by injection timing advancement, so make sure this is operating ok, disconect only one circuit or element at a time otherwise fault finding becomes a hit and miss affair.
Dave
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Gaz
- Posts: 40
- Joined: 05 Jul 2002, 15:22