Hello.

Changed car battery from 027 to 096,so different size, different brand, and more CCA.

Car is 10reg 1.6tdi, 65k miles.

I tried to recode the new battery through vcds, but have found no such choice following the Ross tech website instruction.

 

Do I need to recode? 

 

Car starts fine, drives fine, no errors on dash or vcds, but as soon as in parking position with handbrake on, it making  low buzzing noises,  will disappear if press brake or gas pedals, releasing the pedals noises reappear. Idle is 780rpm showing from dash and vcds.

 

Is this the normal idle learning symptom? 

 

Any ideas?

 

Many thanks

Unless the car has start/stop there won't be any battery related coding possible, I believe.

Thanks.

The car is not a start/stop one.

Upgrading battery to a larger cranking amp will make no difference at all, the only thing that might have happened is that you might have disturbed one of  the air filter pipes when doing the swap, tick over on most diesel engines should be around 900-950  rpm otherwise the anti stall will start to come in and cause a slight surge in the car when it's  going to stall, this is present on most diesels as when it does stall it creates a large bang unlike a petrol engine

Thanks.

I've had the car about 9 years, its idle speed is always just under 800rpm, except cold or doing the dpf regen.

 

This symptom happens on both cold and warmed engine after changed the battery. The car hasn't driven too much, about once a month during this time. 

 

Will increase idle speed through vcds solve this problem?

Or where should I look for ?

 

Many thanks

Are you sure this just started, too? I am unsure as to if you are noticing something "New" That may have already been there but due to the change and your expectation of having to code, etc, you are being over sensitive and finding an issue which may have either already existed or is not actually a fault, just a normal sound.

 

Having said that, I would try my best to get the car on a good run every few weeks anyway as they do hate being left standing for an extended period of time. I think there has been an upsurge in people finding faults with their cars, due to lack of usage, this last year!

Thank you.

I will then try to get it driven more often to see if the noise goes away or any fault code coming in.

 

 

Or try slipping the old battery back in, to see its not causing any issue. I doubt it will make any difference but its only a ten minute job, each way, if you still have the old unit. (Always handy to keep an old one for certain situations, unless it was completely FUBAR or SNAFU).

Thanks for advice.

Don't think that would make difference because I disconnected the old battery for a quite long time, almost a week.

I thought it was a ECU resetting things but I have no idea as you said if this annoying sound was already there.

Will update if had the outcome.