Renault scenic 2001 1.8 - Renault scenic 1.8 misfire/lambda fault ?

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Wed 15 Jan 2014 14:25
Renault scenic 2001 1.8 - Renault scenic 1.8 misfire/lambda fault ? - devonnick

Hi my Renault has a bad misfire /hesitation as soon as it warms up ( it starts and ticks over fine ) had local garage check it over with analyser and it said rear lambda sensor fault..ok got one off ebay £25.00 fitted it still same problem..had garage re check it came up with same fault ( was advised to buy better quality sensor ) purchased another sensor fitted it still same problem..got garage to check again and it is coming up as rear lambda sensor fault ..not sure what to do now thinking maybe wiring fault from sensor to ecu ! if wiring is intermitant open or short circuit would analyser think that the sensor is the problem....any help would be great...thanks.

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Wed 15 Jan 2014 19:58
Renault scenic 2001 1.8 - Renault scenic 1.8 misfire/lambda fault ? - elekie&a/c doctor

I am not convinced that a fault on the rear lambda sensor would cause your running issue.What value/ voltage do you have at the sensor?What happens if you run the engine with the sensor disconnected.?

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Wed 15 Jan 2014 20:20
Renault scenic 2001 1.8 - Renault scenic 1.8 misfire/lambda fault ? - Collos25

Faulty lambdas do not normally make the engine misfire good advice above.They normally when faulty put on the engine management light of course it could always be the catalytic convertor.

Edited by Collos25 on 15/01/2014 at 20:23

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Wed 15 Jan 2014 20:46
Renault scenic 2001 1.8 - Renault scenic 1.8 misfire/lambda fault ? - devonnick

Thanks for your replys. I will see how it runs with it disconected tomorrow...what should I be looking for voltage wise ? ...how do I detect if it is the cat ? sorry for more questions.

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Wed 15 Jan 2014 21:34
Renault scenic 2001 1.8 - Renault scenic 1.8 misfire/lambda fault ? - elekie&a/c doctor

The front and rear sensors are both the same,however the rear works at a much slower rate and within a narrower voltage "window".I would expect the rear sensor voltage to be running between 0.4 and 0.6 volts on the sensor output.A cat is only a filter,it is unlikely to cause any running problems,unless it is blocked.hth

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Thu 16 Jan 2014 10:02
Renault scenic 2001 1.8 - Renault scenic 1.8 misfire/lambda fault ? - hardway

Find a new mechanic!

Yeh Gods!

Of course the lambda reading is going to show a fault,when an engine miss fires that raw fuel is going straight through,

unburnt!!

no way can the cat deal with that.

Ignore pre/post lambda reading until the miss fire is addressed.

And as I'ts a Renault first guess is the ignition coil.

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Thu 16 Jan 2014 20:30
Renault scenic 2001 1.8 - Renault scenic 1.8 misfire/lambda fault ? - devonnick

Hi if it had a coil fault would that not show up on the analyer like the rear lambda did ?

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