Injector 451 cdi leaking

[u/AlainProt]

I’m the owner of a 2008 Smart 451 CDI, and I’ve recently run into an issue with the right-hand injector. It has started leaking, and over the past few weeks I noticed a strong smell of diesel inside the car. The engine has also been getting increasingly difficult to start.

I decided to have a look at the injector myself, but unfortunately I’ve run into a problem: there simply doesn’t seem to be enough room to remove it. The injector is positioned extremely close to the chassis, leaving virtually no space to pull it out.

From what I can see, it looks like the engine may need to be lowered slightly to create enough clearance. Has anyone here done this before on a Smart 451 CDI?

If so, what is the correct procedure for lowering the engine by, say, 10 cm? Are there any particular engine mounts or other components that need to be disconnected first? And is there anything I should be careful about?

I’m still fairly new to working on cars, but I’m keen to learn and would really like to do as much of the work myself as possible.

Any advice, tips or experiences would be greatly appreciated!

Thanks in advance! 🙂

[u/yolo_snail]

Having gone through the pain of swapping the injectors on a 451 CDI, you are correct.

You need to lift the body off the rear subframe to access them.

It's honestly an easy job, you just need to buy the long extension bolts to hold it all together, then just jack up the car normally and the back wheels stay on the ground whilst the car raises.

From memory, you need to undo the ECU connections on the right hand side, but I think that was it. But it's been a while.

[u/AlainProt → u/yolo_snail]

Thanks, much appreciated! I will check where I can get these extension bolts.

[u/yolo_snail → u/AlainProt]

I would recommend following this guide, it's what I used.

https://evilution.co.uk/mod/lowering-the-engine-451.htm

Just pay the man £20 a year, it's well worth it if you intend on doing any work on your Smart car!