Renault Megane 1.5DCI 2003 battery change

[markta]

Hi all,

I have background knowledge in cars, but would welcome a second opinion and feedback.

Yesterday I replaced the original battery with a Bosch Silver Plus 61ah battery, copper greased all terminals (disconnecting each lead as couldn't remove old battery without doing so).

Anyway, car starts perfectly, idles perfectly and did the first 20 mile journey to work today and was fine till final two miles when car is juddering in any gear, mainly around 1800rpm.

Have had absolutely no problems till the new battery was installed, so either I am assuming the 61ah is too high for the engine / system and / or various functions such as alarm / immobiliser need re-setting.

Am I correct? Does anyone have any ideas please?

Thanks

[davelowe]

On some engines, the ECU has to re-learn your driving habits. There is info on here somewhere, I've posted it verbatim from the Haynes manual.

[markta]

Thanks for your help Dave

Would be most grateful if the info could be traced re verbatim.

I suspect like you that the ECU needs "re-braining". An example was today when the electric windows would only go up or down at about 5cm at a time, so had to re program the ECU so that it recognised the open and shut parameters.

I've now come back from another 22 mile journey and the juddering is there a little but she drove beautifully apart from the first mile or so. Idle is constant and no judder/misfires when revving engine.

Mark

[davelowe]

Mark,

See here:

https://www.meganeownersclub.co.uk/forum ... =2&t=12384

[markta]

Excellent.

Thanks for your help Dave!

Just an update...no more juddering so I assume the ECU wanted to take some feedback before making adjustments..ie from EGR valve, lambda and throttle sensor.

She drives very smooth as she was prior to installing new battery

[davelowe]

We aim to please