I start the car in the morning, then turn on the rear heated elements, I then hear the engine vibrate slightly for a second as if it's labouring. Then goes back to normal engine sound.

Anyone else noticed this? Is this normal?

Edited 20 December, 201015 yr by fabia55

Modern vehicles have so many electrical add ons, it is the added load on the alternator, after a cold start. It also means that you will need a lot longer to charge the battery. This time of year you will see on the forum the number of people having battery problems. It is not just the battery but the toys like heated windscreens, heated washers and the electric power steering these will ruin the battery and alternator. Turn off as much as possible.

it's going to take longer to charge battery, and ruin the alternator and battery?!

does your battery not charge whenever the car's engine (and alternator) is turned on?

Modern vehicles have so many electrical add ons, it is the added load on the alternator, after a cold start. It also means that you will need a lot longer to charge the battery. This time of year you will see on the forum the number of people having battery problems. It is not just the battery but the toys like heated windscreens, heated washers and the electric power steering these will ruin the battery and alternator. Turn off as much as possible.

Yes, it is the added load that momentarily dips the engine speed (esp in a 1.2 12v) but with a 70+amp alternator there is no need to worry about battery not recharging even with all your lights/heaters/gizmos on (with possible exception of a multi kw boom box)

Problems at this time of year are usually due to old batteries and short runs with partially discharged batteries perhaps due to leaving lights/radio on when the engine is off.

Edited 21 December, 201015 yr by xman

Yes, it is the added load that momentarily dips the engine speed (esp in a 1.2 12v) but with a 70+amp alternator there is no need to worry about battery not recharging even with all your lights/heaters/gizmos on (with possible exception of a multi kw boom box)

Problems at this time of year are usually due to old batteries and short runs with partially discharged batteries perhaps due to leaving lights/radio on when the engine is off.

that's worrying if it's only about 70amps. i hope it's actually more than that. i have an amplifier albeit quite efficient and only 250watts rms, but later will be adding another amplifier probably 400-600 watts rms, it's only for normal music listen at normal volumes (no need to shout) In that case i'll not turn on my amp. I think i'll listen to stuff without much bass when it's cold

how come it's only when i turn on the rear heated element, nothing else seems to make the engine change sound

Edited 22 December, 201015 yr by fabia55

The rear heated screen is renowned for requiring a lot of electrical power - on all cars, probably one of the highest single electrical draws.

well if it's designed to be used, then i will use it whilst my car's still under warranty

I start the car in the morning, then turn on the rear heated elements, I then hear the engine vibrate slightly for a second as if it's labouring. Then goes back to normal engine sound.

Anyone else noticed this? Is this normal?

Well thats the asthmatic little 1.2 having to become an electrical generator to power the thirsty heating elements. Perfectly normal. The load will decrease as the elements warm up as electrical resistance increases with heat so you use less power. Still a high load though. Provided you let the battery fully charge and not do loads of short journeys with all the electrical gizmos on you will be fine. If your worried then get a charger and top up the battery at the weekend during cold spells. Batterys that arent maintained at peak charge lose capacity and lifespan due to sulphidation of the plates.

My diesel has a lot of torque so I dont really notice it

My old nissan used to actually 'idle up' when an electrical load went on the engine just to stop the engine labouring a bit.

A 600 watt amp is going to be drawing close to 40 amps at full beans. Perhaps a soothing ballad rather than banging fat tunes in the winter months Oh dear I sound like my parents

Edited 22 December, 201015 yr by raisbeck

i'm a little worried about my amps putting too much strain on the electrical system. I think i'll invest in extra sound proofing so i don't have to turn the volume up on the motorway.

people think that because i have amplifiers and upgraded speakers, etc. I am one of those who play loud with thumping bass but in actual fact far from it, i don't listen to dance/hip hop or anything with thumping bass. i listen to a lot of acoustic and softer stuff. I think i won't turn my sub amp on when it's cold.

I haven't noticed the Rear Screen Heater cause the engine to labour at all. One thing I would strongly recommend this weather. Before starting the car, switch OFF all electrical items such as fan, Aircon, Heated rear screen etc., then once the engine is running try to avoid usind the rear screen heater, lights and say, the fan on full at the same time. Try to minimise the amount of load you place on the battery at this time of year. This won't be as necessary for those doing high miles but for people such as me who's car sits on the drive and is only used (in this weather) for short trips it is important to 'nurse' the Battery so as not to empty it. :'(

I haven't noticed the Rear Screen Heater cause the engine to labour at all. One thing I would strongly recommend this weather. Before starting the car, switch OFF all electrical items such as fan, Aircon, Heated rear screen etc., then once the engine is running try to avoid usind the rear screen heater, lights and say, the fan on full at the same time. Try to minimise the amount of load you place on the battery at this time of year. This won't be as necessary for those doing high miles but for people such as me who's car sits on the drive and is only used (in this weather) for short trips it is important to 'nurse' the Battery so as not to empty it. :'(

This is for most part true...But... (you knew that was coming didn't you)? It CAN be of some benefit to have something, like sidelights on prior to starting, in order to "Warm" the battery up a little before trying to start in colder weather.

Don't go bonkers though and use too much power or the battery will just struggle.

This is part of the reason you can only use sidelights with the engine off in many newer cars. Dipped or full beam would remove too much power, as will the rear heated window. In the Fabia, you can ONLY turn the heater on after starting the engine and if you forget to turn it off, it will self cancel after 20 mins... However, if you subsequently re-turn it on, it will stay on until the ignition is switched off or the battery dies, which ever comes first! :p

It CAN be of some benefit to have something, like sidelights on prior to starting, in order to "Warm" the battery up a little before trying to start in colder weather.

This is part of the reason you can only use sidelights with the engine off in many newer cars.

Never heard that before. Drawing unnecessary power from the battery just before a high draw cold start doesn't make sense to me.

Being able to leave side lights on without the ignition on is for parking at night on cars not equipped with parking lights.

i'm a little worried about my amps putting too much strain on the electrical system. I think i'll invest in extra sound proofing so i don't have to turn the volume up on the motorway.

That's got to be better for your ears and long-term hearing too.

That's got to be better for your ears and long-term hearing too.

yes as we age our hearing deteriorates. less vibrations less wear and tear in our ears. i'm not medical but it wears out the 'hair' things in our ears.

so better to avoid noisy environments like driving on the motorway unless the car is well sound insulated

This is for most part true...But... (you knew that was coming didn't you)? It CAN be of some benefit to have something, like sidelights on prior to starting, in order to "Warm" the battery up a little before trying to start in colder weather.

Don't go bonkers though and use too much power or the battery will just struggle.

This is part of the reason you can only use sidelights with the engine off in many newer cars. Dipped or full beam would remove too much power, as will the rear heated window. In the Fabia, you can ONLY turn the heater on after starting the engine and if you forget to turn it off, it will self cancel after 20 mins... However, if you subsequently re-turn it on, it will stay on until the ignition is switched off or the battery dies, which ever comes first! :p

The only way you can "warm" the battery in that way is to take power from it, NOT recommended in this weather in my view but each to his own.

Edited 26 December, 201015 yr by horkin