Unfortunately, there is not really any maintenance you need to do in most cases. Most vehicle owner’s manuals will advise you when your Glow Plugs should be changed. At Champs Family Automotive, we recommend, at a minimum, replacing your Glow Plugs every 100k miles. On more modern Diesels (2004/2005 and newer) you can get a check engine light that may come on if you are having a problem with your Glow Plugs. On these more modern Diesels the onboard computer registers the amperage of each Glow Plug. If your Glow Plugs fall outside of their optimum operating amperage a check engine light may come on. Most older Diesels (2004 or older) will usually give you little to no warning signs that your Glow Plugs are failing, which is why it is always better to be proactive versus reactive. If you do not change your Glow Plugs before they fail, repairs can get very costly.