AndrewInSeattle
Senior Member
It was -10F overnight, it's still below 0F when we wanted to start, but cranking the engine was not going well. Super-cold weather is rare for us, so we don't have a block heater or other modifications, although we have learned to buy diesel locally to get the winter formulation, and typically add a bottle of HEET anti-gel when filling up on a ski trip. We also got a brand-new higher amp-hour van battery last year, after a significantly worse winter experience.
Anyways... Turning the key all the way and holding it led to a weak but improving cranking sound, almost but not quite catching, and after 20-30 seconds the dot matrix display -- sluggish due to the cold -- popped up a giant red battery warning, causing me to panic and let go. My wife, on the other hand, owned an old diesel Rabbit in her youth, and her instinct is to just keep going based on the cranking noise, ignore the warning, and (as usual) she turns out to be right.
All is well now, but we have questions about what exactly is the most reliable way to start in cold weather.
- I thought the glow plugs were supposed to stay on a while in cold weather, but the indicator light on the dashboard only comes on a split second regardless. I found some suspicious advice online advocating a complex dance of turning the key to ON (but not START) many times before attempting to start, not sure if that was BS or not.
- Is the battery warning actually significant? Once I stopped panicking and actually read it more closely, I think it was just saying that the battery would need to be recharged by leaving the engine running for a bit. But it was big and red!
- How long is too long to crank without catching?
- To what extent, if any, does the house battery "help out"? We have a 7.5-year old 210Ah AGM behind a BlueSea 7620 ML-ACR battery separator, installed by Sportsmobile West, and it remains a mystery to me when/if the house battery will assist the van battery in a crisis.
- On the second morning of -10F weather, we planned ahead and parked within range of a shore power outlet. While still plugged in, I was able to crank the engine until it caught, maybe 30 seconds, without seeing the giant red battery-needs-to-charge warning. Not sure if that was just a coincidence, or the house-battery charger was providing extra amperage through the BlueSea so the van battery never experienced a noticeable voltage drop. Does that sound plausible? Is starting the van while plugged in dangerous/harmful? [Let's ignore the risk of driving off while plugged in, which I swear I've only done once!]
Anyways... Turning the key all the way and holding it led to a weak but improving cranking sound, almost but not quite catching, and after 20-30 seconds the dot matrix display -- sluggish due to the cold -- popped up a giant red battery warning, causing me to panic and let go. My wife, on the other hand, owned an old diesel Rabbit in her youth, and her instinct is to just keep going based on the cranking noise, ignore the warning, and (as usual) she turns out to be right.
All is well now, but we have questions about what exactly is the most reliable way to start in cold weather.
- I thought the glow plugs were supposed to stay on a while in cold weather, but the indicator light on the dashboard only comes on a split second regardless. I found some suspicious advice online advocating a complex dance of turning the key to ON (but not START) many times before attempting to start, not sure if that was BS or not.
- Is the battery warning actually significant? Once I stopped panicking and actually read it more closely, I think it was just saying that the battery would need to be recharged by leaving the engine running for a bit. But it was big and red!
- How long is too long to crank without catching?
- To what extent, if any, does the house battery "help out"? We have a 7.5-year old 210Ah AGM behind a BlueSea 7620 ML-ACR battery separator, installed by Sportsmobile West, and it remains a mystery to me when/if the house battery will assist the van battery in a crisis.
- On the second morning of -10F weather, we planned ahead and parked within range of a shore power outlet. While still plugged in, I was able to crank the engine until it caught, maybe 30 seconds, without seeing the giant red battery-needs-to-charge warning. Not sure if that was just a coincidence, or the house-battery charger was providing extra amperage through the BlueSea so the van battery never experienced a noticeable voltage drop. Does that sound plausible? Is starting the van while plugged in dangerous/harmful? [Let's ignore the risk of driving off while plugged in, which I swear I've only done once!]
