Hey Scotty. I have a 2014 Volkswagen Jetta Sportwagen TDI with 35,000 miles. Vehicle has trouble starting on cold start, especially in winter (from Michigan). Took it too dealer, says bad battery, had it replaced, problem still occurring. Problem goes away if I use Power Service diesel additive. Currently at the dealer getting checked again. What are some things that could be causing this? Thank you
Your diesel sounds like it’s gelling or your fuel filter is freezing which the additive is helping prevent against.
Are your glow plugs working?
I believe my glow plugs are working? I know the glow plug light stays on longer when its cold out and I make sure the light turns off before I start the car. No check engine light. Is there an *easy* way to check to see if they are working properly?
Then they’re probably working fine. If you still want to check them - https://youtu.be/Se04B8-7fiY
If the problem goes away if you use Power Service, keep using it. I use it every tankful on my 2012 Golf TDI. I use the winter anti-gel type when it gets cold and I've never had that issue. I really recommend using Power Service year round every tankful, just switch types in winter and summer. As I understand it, it will help prevent issues with your fuel pump (expensive fix if it goes out).
Also, to make it easier I buy the large jugs of it but I have saved a bunch of 5.25 oz bottles from other stuff (I use Lucas fuel additive in my gasoline truck so I saved them up over time), I keep a funnel in the garage and just fill up 5 of those bottles and when I get home after a fillup I just pour one in. Which reminds me, I need to do that as I filled up today 🙂 /p>
Edit: Let me add that if has issues even in summer, that is a bit odd....I would make sure all the maintenance was done on it, especially making sure the fuel filter has been changed as it should. But, I'd still use Power Service year round no matter what.
