Location and change of fuel filter MERCEDES-BENZ C-Class Saloon (W205)

Yep, @S. you just need to remove that plastic engine cover first. There's one 90-degree turn clip at the front – takes literally 10 seconds to undo. Once that's off, the diesel filter is dead centre. I managed it myself last year without much hassle.​

Ah mate, I tried doing this myself and ended up at the garage anyway. The tricky bit wasn't finding it – it was disconnecting all the hoses without making a proper mess everywhere. My mate did his w205 and had fuel dripping all over the engine bay. Just be careful with those fuel line clamps when you undo them.​

@johnson19 Spot on with the engine cover. Takes maybe 2 minutes tops. The filter itself is held by two side clips, and you've got the electrical connector to unplug before you slide it out. The real drama is getting the old fuel hoses off – might come in handy to have some grips or a small screwdriver handy.​

One thing I'd add – make sure the engine is absolutely cold before you start, and disconnect the negative battery terminal first if you're the cautious type. Also don't forget that changing the filter on a diesel means you'll need to prime the fuel system afterwards. Start the engine button twice without pressing the brake, then fire it up properly.​

I found it really helps to clean the area around the filter before you start work. Takes literally 15-30 minutes once you've got the cover off. The replacement interval is about 75,000 kilometres or every three years, so you shouldn't need to do this too often.​

The fuel filter on that diesel engine is an in-line filter type, so it's fairly compact. Not like some of the older models where you'd need to jack the car up and work under the rear. Much easier access on the W205 being right there in the engine bay.​

@George White 🏴󠁧󠁢󠁷󠁬󠁳󠁿 Yeah, I always use a bit of silicone spray on those old hose ends when they're being stubborn. Makes getting them off the filter connections much easier without damaging the rubber. Honestly though, unless you're regularly doing this sort of work, it might be worth having the garage sort it whilst doing your service.​

Harper The Bluetech engines are pretty reliable on the filter side. I got my replacement from a local supplier and saved myself a bit compared to going through the main dealer. Just make sure you get the right one – there are a couple of variants for the W205 depending on your exact spec.​

@iMartin.8 Totally agree about those electrical connectors. There's a little tab you squeeze and it slides right out, but if you're not careful you can break that tab. My first attempt I gave it a good yank and nearly snapped it. Just a gentle squeeze and pull this time around.​

Don't forget to check those fuel line hoses themselves whilst you're at it. If they're looking a bit cracked or hard, they might benefit from replacement too. Some people swear by upgrading to worm-drive clamps instead of the crimp ones as well.​

Brilliant thread this! Exactly what I was looking for with my C200d. Sounds like the main thing is just having patience with those fuel connections and not rushing it. The actual filter itself is easy peasy once everything's disconnected. Cheers everyone!​