eightinavee
Well-Known Member
Rasheed is right,but after only swapping one oxy sensor the engine ecu will soon see its output and start trimming the injector pulse width and the long term trims will come back right.Unless it was running for a long time like a complete dog,I wouldnt worry about it.
adamrharding
New Member
I may be applying this idea in a totally incorrect place but I know that disconnecting the BeCM from the battery for 30 minutes depletes its internal battery and is the equivalent of the reset switch on a PC. Is there this kind of option for the engine ECU? You do have to reset the windows and sun roof, but works a treat.
ive changed both o2 sensor and maf has been running bad since ive owned it and trying to cure the problem after ive changed the 02 sensor came up with 02 sensor high voltage if this has any significance to the problem am out of ideas now just runs badly with low idle and chucks out black smoke if you rev it hard and just stinks of fuel it ticks over normal for a few mins till warm then idles low as if cold start (choke) is not working ?????
eightinavee
Well-Known Member
It sounds like the oxy sensors are failing to step down to 0v giving a rich signal,where did the sensors come from ?
i brought them from ebay but were brand new and boxed and the correct part so would not have thought so but i guess its possible what should they change to from as think when i data logged it they were just reading 5 is this 5v? and also had a fault code 02 sensor high voltage ?
eightinavee
Well-Known Member
So are the oxy sensors genuine NTK ones,with the correct plugs etc ? if they are giving out 5v all the time, the engine will run very rich as the ecu is seeing the 5v as a lean reading and will drive the injector pulse width as wide as possible.If the sensors dont switch down to 0v showing a rich signal to the ecu it will just stay rich and stink etc.
yeah they are i think defo had correct plugs was no need to alter any wiring could there be any other reason for not switching other than a faulty 02 sensor for example maybe the wiring pre plug to the sensor etc as would be suprised if both sensor were faulty to be honest but then this is a rangerover lol
eightinavee
Well-Known Member
You need to check the heater circuits for them,if the sensors are not being heated they simply wont switch unless the engine is in a high load /speed situation.
