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I've found that 3mm may be too tight. Try to get about 5 feet of 3.5mm. Also get about 15 feet of 4mm, it will go on easily and is probably a better choice for some of the larger ports. So about 35 feet for both cars. This should be enough as long as you don't butcher the lines while cutting them. Those are inner diameter, outer diameter doesn't matter as much as long as it's not huge (and it won't be for these small hoses)

Here is a good source to get it from:


The only one which isn't on the diagram below is the ecu hose. If you haven't replaced the hose inside the mk3 ecu, it'll go sooner or later and set a CEL (MIL) (check engine light). See http://www.myturbodiesel.com/1000q_how_to/a3b4/ecuhosechip.htm for the replacement procedure.


The 3 mm silicone will stretch if it's too tight, so if you can't find 3.5mm I wouldn't worry about it. The 3mm isn't as stretchy and feels harder but I've found it best for connecting to the thin hard white vinyl tubing that is used in some places instead of the rubber tubing.

Welcome to the forum! If you look through the FAQ links that begin with "1000q", you can find a lot more info. It's organized by mk3, mk4, general diesel knowledge, etc.
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