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My Montego 2.0TD has taken up smoking, mainly at idle and clouds when pulling away and it stinks of unburnt fuel. I had a problem with the EGR valve being held open at idle (there was a vacuum applied to it when I pulled the tube off) . . . it doesn't happen now.
After checking things out and getting it to stop smoking I did a 180 mile motorway journey it was fine, checked under the car the next morning not a drip of oil or water; did several short trips and had the smoke problem; Very cautiously at first, set off on the return 180 mile journey - got home without a problem at "normal" motorway speeds.
What seems strange are the resistance readings from the throttle pot. The lowest reading between pins is 900 ohms and the highest 1950. There is a constant reading of 1050 ohms between to pins which suggests that the "wiper" connection has a resistance of 900 ohms . . . that doesn't make sense. Washing it out with meths hasn't made a difference.
Air Filter - new
EGR - cleaned and tested
PCV Valve - cleaned
Cold Starting - Good
Power - Good (but fiddling with the throttle pot can cause a horrendous flat spot - power loss/turbo lag.
The temperature switch and cold start solenoid work;
The temperature switch for the automatic advance works and power is getting to the solenoid (about 25 ohms) but I can't tell if the solenoid operates (with the engine hot disconnecting makes no difference) and Mr "Haynes" doesn't give any clues about how it comes apart.
This problem is driving me mad! It seems to me as though there is too much fuel or it is not getting burnt properly at idle, the EGR is closed (tube off and plugged).
If anybody can help with voltage and resistance readings for the EGR system inc. valve lift pot) and a link to diagrams for the advance solenoid assembly (or 'it's only a spring and a plunger just undo the big nut' reassurance). I would be really grateful. I've got access to a vacuum gauge, meters and 'scope but I don't know what I'm looking for.
Thanks in anticipation.
After checking things out and getting it to stop smoking I did a 180 mile motorway journey it was fine, checked under the car the next morning not a drip of oil or water; did several short trips and had the smoke problem; Very cautiously at first, set off on the return 180 mile journey - got home without a problem at "normal" motorway speeds.
What seems strange are the resistance readings from the throttle pot. The lowest reading between pins is 900 ohms and the highest 1950. There is a constant reading of 1050 ohms between to pins which suggests that the "wiper" connection has a resistance of 900 ohms . . . that doesn't make sense. Washing it out with meths hasn't made a difference.
Air Filter - new
EGR - cleaned and tested
PCV Valve - cleaned
Cold Starting - Good
Power - Good (but fiddling with the throttle pot can cause a horrendous flat spot - power loss/turbo lag.
The temperature switch and cold start solenoid work;
The temperature switch for the automatic advance works and power is getting to the solenoid (about 25 ohms) but I can't tell if the solenoid operates (with the engine hot disconnecting makes no difference) and Mr "Haynes" doesn't give any clues about how it comes apart.
This problem is driving me mad! It seems to me as though there is too much fuel or it is not getting burnt properly at idle, the EGR is closed (tube off and plugged).
If anybody can help with voltage and resistance readings for the EGR system inc. valve lift pot) and a link to diagrams for the advance solenoid assembly (or 'it's only a spring and a plunger just undo the big nut' reassurance). I would be really grateful. I've got access to a vacuum gauge, meters and 'scope but I don't know what I'm looking for.
Thanks in anticipation.
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