Good ol’ maintenance items that shouldn’t be maintenance items. This is definitely something that should be checked often, especially if you have a tune and/or HPFP upgrade. Yes, we are talking about the infamous cam follower. It can cause loads of issues if not properly maintained, almost requiring a full top end rebuild.
You will need:
- Part # 06D109309CKT Cam follower kit
- Stubby style XZN socket set
- STUBBY 17mm wrench
- Socket wrench
- 12” extension
- Electrical tape
- T30 Torx bit
Luckily, this isn’t a very hard part to replace. After you do it your first time, you can probably pull it off in about 15-30 minutes. First things first – make sure the engine is cool. Some gasoline is going to squirt out when the pressure is bled (the high pressure sides runs at something ridiculous, like 145 bar) and the last thing you want is essentially aerosol gas hitting hot engine components. Now unplug the connection on top of the high pressure fuel pump by pushing the L shaped connect back, and then pulling it off. Repeat this with the white sensor hiding under the fuel line.
Some people recommend to pull the fuse for the fuel pump so it doesn’t try to prime while you are working on it – just don’t open your driver side door while you are working on your car and you’re good to go. At your own discretion though. Use a punch or something to poke the bleed nipple that is located facing towards the firewall; it is brass. There is a valve similar to a tire valve that just needs to be pushed with a rag handy to catch the fuel that bleeds out.
Next take an M8 XZN socket, such as the stubby style XZN socket set that I like to push, and attach that to a long extension. You’re going to need about 16 inches to reach the banjo bolt. Come up from underneath the engine like so, and fish the contraption through until you can seat it in the bolt. Look at where the flashlight is shining and you can see the bit coming up from underneath.
Now loosen it up and make sure you don’t drop the banjo bolt. This tends to be my most time consuming part of working on this car. Transmission ribs and the k member are good hiding places to look for lost pieces by the way.
Using a 13 mm spanner, remove the bleed nipple to allow access to the T30 bolts.
Now, take a STUBBY 17mm wrench and remove the hardline. You want the stubby because of the tight clearance between the back of the engine and the firewall. Even if you manage to get it loose with something else, tightening it will be a whole new hassle. May as well remove the vacuum pump fittings to free up some wiggle room too. Just invest in the right tools – can’t preach that enough.
Almost there already. Remove the 3 T30 Torx bolts holding the HPFP onto the engine, and give it a slight tug up and out. It should pop right off. Voila, already have it off.
Take your finger and fish out the cam follower taking note of the condition of the surface that interacts with the cam and HPFP tip. If the black coating is almost worn through, you caught it just in time. If it looks rough, inspect the cam it rides on along with the HPFP tip for any scouring/scratches. If you were getting codes before this for fueling issues or it looks like it has been abused, you most likely need to investigate replacing your cam. God speed.
If not and everything looks to be in good shape, lets reverse the order. Before this, replace the seal on the end of the the HPFP and coat it with some engine oil . Take your new cam follower and soak it with a bit of your engine oil for a few minutes, then place it back where you fished the other out. Place the HPFP back into its home, and use NEW bolts provided in the kit to begin torquing the bolts down in an even matter. As in, don’t just crank one down and expect the others to follow. Continually move in a cross pattern to keep pressure even throughout all the bolts. It is actually pretty common for people to strip these bolts out. The torque spec is low at only 10 Nm.
A trick I like to use is to electrical tape the banjo bolt onto my XZN socket, and then come back up behind the engine the same way I loosened it up. This stops me from having to hunt every time I drop it and it will come off easily enough when I am done tightening. Now reattach the hardline and tighten it up with your super convenient, now I know why I bought this, expensive little stubby wrench thing.
That’s it – a small job to prevent potential catastrophic engine failure. Cycle the ignition to accessory a couple times so the fuel system has a chance to prime. Crank the engine over for a bit. This may take some cranking since you just bled out all the fluid in the lines, and then check for leaks. If there isn’t a gas smell or any obvious leaks, beer time. Cheers!