Replacing cruise control vacuum line on a 1998?

[1337]

My car is a 1998 with the vacuum-based cruise control. It has a vacuum line that runs from the cruise control pump (under the battery) to the gas pedal. When I bought the car, this vacuum line had a hole in it. As a short term fix, I wrapped the hole in electrical tape, and the line holds pressure.

But, I would like to fix this "the right way." I think the 100% fix is to replace the whole vacuum line. I have a couple of questions about this:

1. What should my shopping list be for this repair? I bought a length of silicone vacuum line with 3.5mm inner diameter. But the outer diameter of the silicone line is way too fat to fit in the Volvo vacuum elbows. None of the local auto parts stores seem to carry plastic 3.5mm vacuum line. Any suggestions on what to buy, and where to buy it?

2. What parts should I remove to access the vacuum line? It looks like the fuse box is in the way... what else should I remove?

[erikv11]

When I have done this job, I left the hard plastic line intact where it goes through the firewall, and left it all intact on the cabin side. So, remove the air filter box and maybe the battery, clip out the hard plastic line back near the firewall, then reconnect with silicone line that fits tightly over the plastic line and run it up to the cruise pump. The same line will fit snugly on the cruise pump. Clamp or zip tie the silicone over tghe tubing if needed, but if you feed in a good length of plastic tubing you likely don't need to.

I would get rid of any rubber elbows, just use silicone line as it is so flexible. The rubber elbows can be problematic, and age much more quickly than silicone.

[dyn blin]

I tried the replacing with the rigid stuff similar to the OE, spent a bunch of frustrating time re-fishing it through the firewall, and even then ended up replacing with silicone from the firewall after it failed again in few years- if I recall correctly, 6mm fits snugly over the rigid tubing as it comes out of the firewall and fit the pump nipple securely. To make it a bit easier to inspect, I routed along the inside of the engine bay just below the level of the hood, and over the top of the battery tray. That way, the majority of it can been seen (and cleaned) to troubleshoot any later leak.

The junction through the firewall is pretty close to the brake pump, and hard to reach with my hammy mits, so I left a few inches of the hard hose to work with before attaching the flexible silicone. It's nice to choose another color too, to differentiate it when you're digging in there months later on another project