MI light continous indication and rough engine

[Bausek]

Dear lotus drivers,
I have just bought an elise MKII 111S in the UK and imported to Austria. It was a long drive....The car runs great when it is cold and on short drives. But if you go on the highway after about 1/2 hour (depends on the outside temp.) the MIL light goes on and the engine runs rough at low throttle. Has anyone had ever a similar problem, or can somebody say me where I should start to change parts? Oxygen sensor? Catalytic Converter? Spark plugs?
Thanks in advance for your effort. Regards David

Edited by Bausek on Thursday 23 April 00:11

[RGelise]

Is the car fitted with a cat or bypass pipe?

[JTBUSH]

Remove all ignition leads and check for moisture, especially down spark plug holes. Disconnect all leads and give the contacts a good clean.

If it isnt this, it could be a sensor, and if it is when the engine is warm, maybe crank position sensor

[djroadboy]

If the MIL light is on I would recommend getting the fault codes read before changing anything. No point in spending money on parts that may not need changing.

Most likely to be primary lambda sensor or a coil pack.

HTH

Dan

[RGelise]

The reason I ask about the cat being fitted before, is because when the car is at speeds over 56 mph for longer than 6 minutes the ECU performes a catalyst check (only on S2 model). If it sees very little differance between pre and post lambda sensors is logs a fault for the catalyst. For this reason you need an MIL illiminator if the car is fitted with a bypass pipe. As your car runs O.K at low speed, I would look at this first. Get the codes read. As djroadboy said this is the cost affective root. Fined out the fault code first as this will be logged if the light is on.

Edited by RGelise on Thursday 23 April 13:46

[row10036802]

Plugs and leads, i had one only the other day with exact same problem.

James

[Bausek]

Thank you for the many many answers, I will spend first the money on a OBDII reader, because I didn´t know about the failure codes. I just thought that the MIL light is only responsible for the LAMBDA, because I am a new lotus owner. I have already downloaded the codes, just need the OBDII. Can you recommend one??
Hope to some of you one day in the Austrian mountains....accomodation just smal, but available.....
Thank you in advance I will let you know about my further investigations.....

[purpleperil]

Bausek said:

Thank you for the many many answers, I will spend first the money on a OBDII reader, because I didn´t know about the failure codes. I just thought that the MIL light is only responsible for the LAMBDA, because I am a new lotus owner. I have already downloaded the codes, just need the OBDII. Can you recommend one??
Hope to some of you one day in the Austrian mountains....accomodation just smal, but available.....
Thank you in advance I will let you know about my further investigations.....

Just purchased a Maxiscan MS509 from www.talktomycar.co.uk - next day delivery if order placed before 3:30. They have lower cost versions available but the 509 has lots more features and works fine with the 'yota S2.