Will a dead glow plug cause any problems if not replaced ? Have seen the post explaining how to change plugs, changed all mine (Bosch) about 2 years back back and one showed up dead on its last service (short life due to incorrect fitting ?)  Wish that post had been available then, hard work getting plugs in and out ! No problem starting (first time, nice big Varta battery)  even when left for a week at -8C

 

Cheers 

 

Lloyd

I've had three out for over a year now and still starts 1st turn of the key, even in -5 degrees and with a 10 year old original factory fit battery. I will wait until starting takes more than a second or I get lumpy running straight after a cold start before I bother to change them (This is on a 173k mile car as well)

Interesting this, because we had the glow plug light come on during a drive to and from Austria last year, but on short runs it would never appear. We then took a 300 mile trip just before Christmas and the same thing happened - very cold -7C. I think these are the original glow plugs at 165K, so should I replace them?

I've had problems with poor starting on another diesel but never the 1.9PD unless you count a goosed battery.

 

Even down to near freezing it will start first time without waiting for the glowplug indicator to extinguish, just turn the key and it starts so I can't imagine dud glowplugs will make a difference to 90% of UK weather starting.

 

I understand in extreme cases they can disintegrate and cause internal damage but until it caused starting issues I would just leave it.

26 minutes ago, andyoctavia said:

Interesting this, because we had the glow plug light come on during a drive to and from Austria last year, but on short runs it would never appear. We then took a 300 mile trip just before Christmas and the same thing happened - very cold -7C. I think these are the original glow plugs at 165K, so should I replace them?

The glow plug light indicates a number of potential issues but interestingly none of them are a failed glow plug. You need a VCDS scan to see what caused the light.

5 hours ago, phoneman(ret) said:

Will a dead glow plug cause any problems if not replaced ? Have seen the post explaining how to change plugs, changed all mine (Bosch) about 2 years back back and one showed up dead on its last service (short life due to incorrect fitting ?)  Wish that post had been available then, hard work getting plugs in and out ! No problem starting (first time, nice big Varta battery)  even when left for a week at -8C

 

Cheers 

 

Lloyd

 

There may have been carbon build up around the glow plug when installed. If you decide to change it, it might be worth using a reamer kit to clean the port in the head first

Is was told I had one glowplug out over 2 years ago when it is was in for a service at my local dealer. They asked if I had any issues with starting and when I said it was starting fine then they advised me to leave it until it did cause issues (this is on a 2010 VRS CR170). So I have left it and it has been fine, since the car is being part exed for a new 280 Superb on Friday then it is a cost I have avoided.