Skoda Octavia - black smoke and high consumption

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Wed 9 Nov 2011 04:26
Skoda Octavia - black smoke and high consumption - bonbon

hi , can any one help me plz i have1998 skoda octavia 1.6 aee engine code it has 170000 km in good condition but it has one problem it has a black smoke from the tail pipe and a high fuel consumption i changed the engine control unit , spark plugs ,timing belt , water temp sensor , fuel and air filters but still have the same problem i dont know what to do

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Wed 9 Nov 2011 09:05
Skoda Octavia - black smoke and high consumption - injection doc

changing all these parts my friend is not the answer. I sugest you find someone with a diagnostic tool and check live data,

get the following checked

Coolant temp sensor reading in degrees and voltage

Airflow meter/map sensor reading, if this car is fitted with a MAP sensor then it should read around 500mb at idle, if its low then iether the sensor is faulty or you have an air leak which will make it run very rich

Check injector duration, typical hot at idle would be around 2.5ms

If all the above are correct check the fuel pressure, if the pressure control valve has failed the pressure may be running at 3.5-5 bar ! this will make it run very rich but no faults will appear and readings will be correct other than Lamda sensor control

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Wed 9 Nov 2011 10:53
Skoda Octavia - black smoke and high consumption - Bromptonaut

I don't know the Skoda but generally a check of the induction pipework for splits leaks would be in order as well.

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Wed 9 Nov 2011 11:06
Skoda Octavia - black smoke and high consumption - Cris_on_the_gas

black smoke normally injectors, after that mileage they probally need a clean up

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Wed 9 Nov 2011 11:46
Skoda Octavia - black smoke and high consumption - bonbon

iam trying a fuel injector cleaner

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Wed 9 Nov 2011 11:43
Skoda Octavia - black smoke and high consumption - bonbon

thanks alot for the readings i really needed it . i went before to service center and they changed all the parts i mintioned the vag-com says lambda sensor g 39 and engine control unit blocked thats why i changed the ecu but nothing happened and they have reading from lambda sensor for three minutes after cleaning it so the engineer said it is fine untill it has carbon on it ,they recommend tearing the upper half of the engine to check the valves gaps but iam not agree ,iam using now fuel treatment to clean the injectors ,hopefully if it is clean i will change the spark plugs again and clean the sensor again to see if it is ok ,

sorry to give u headach but this is my first skoda and it cost my fortune in my country to buy it it is about 8000 us dollars here

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