2010 JSW TDI with 35K miles and original battery

I bought my JSW this past May with 30K miles on it. This is my first diesel vehicle. Since the temps have started to drop here in Minneapolis, I've noticed after it's sitting outside all day while I'm at work, it hesitates for 2-3 seconds after turning the key to start before turning over. I noticed the battery is the original so figured it must be related to that. I had the nearby Batteries Plus test the battery and much to our surprise, it tested out at 738 CCA! He looked up the specs for my car on the Batteries Plus computer and it says it requires 540 CCA. So, if that's the case, my battery should still be good and not the cause for the hesitant starting. Is hesitant starting normal for TDI's in colder temps (below 40F)? Being from Minnesota I feel funny saying below 40F for colder temps cuz that's not cold at all; it'll easily be below 20F for weeks at a time this winter. And I love it, I'm an avid cross country skier! 20-25F is the perfect temp if you ask me.

A friend of mine used to have a late 2000's Jetta TDI and remember something about turning the key then waiting 5-10 seconds for a light to come on on the dash panel before starting it.

Please let me know what you think. I plan to stop at my local VW dealer in the next week to have them test the battery and see what they think.

Also, for about the last week when I start my car, the dash message center says "X days til service." I checked the manual for more info on this, but no luck. What type of service is this referring to? I had the oil changed in June with 31,000 miles and was planning to go with a 10K OCI.

Thanks!

First, if it is cold outside, you should wait for the glow plug light to go out on the dash board before turning the key. Second, batteries have a finite life. Why hesitate to replace it if you aren't sure? If your car isn't driven every day, the battery doesn't get recharged.

Cold Starts

Diesels detonate based on compression not spark like gasoline.

No matter how cold a gasoline engine is as soon as a spark is added to a flammable substance (fuel), in the presence of oxygen, it will ignite.

Diesel:
By warming up the glow plugs detonation can then be achieved at a lower pressure. This is why there is a delay period until the glow plug light comes on. It is warming up the glow plugs before it builds up the pressure mechanically (cranks). That is why you should not turn the key to start the engine as soon as you put it in. Having said that I don't know how the push-to-start models work (I know you don't have one).

As far as the battery... Since it tested at higher than the OEM CCA it seems to be in better than new condition? I don't understand why that is an issue. If you want peace of mind then that is a whole different thing.

Congratulations, your 2010 has almost the same miles than mine! PO parked mine all winter for four years and only drove it in summer on the highway! Battery in that car is fine started easily below 0F last winter. My 05 still has the original battery and is cranking OK in the mid 20s, but I don't think it will survive this winter.

I don't know what size the 2010 battery is but for the 05 a new 94R battery should have about 800 CCA. 540 CCA does not sound right at all as a spec. but if mine tested at 738 I would not worry about it. Wait until the glow plug light goes off and the engine should start almost instantly. If there is a hesitation after you turn the key I would be suspicious of the starter or solenoid having problems as a result of low use.

The message on the dash means that when the oil was last changed the service interval was not reset. It is reset via the MFD, one of the options, I think it is in the setup menu?, is "reset service interval".

As another thought, if you don't know when the pano roof was last lubed, get that done. They break if not lubed and replacement is very expensive. I think it is a 2 year interval on the roof lube.

It's time to replace the battery. The CCA should be at 850 to 32* and 680 at 0*