Hi!
I would like to delete the cold start injector on my 1990 240. I have the Volvo kit that covers the hole on the intake manifold. I need to know what sort of cap nut to put on the fuel rail. I'm guessing stainless steel. The fuel line screws in with a 14 mm width nut. Any idea what size of cap nut to use? My local hardware store was not of any help. Thanks.

my 1989 had a cold start valve that had been rendered superfluous when the dealer replaced the ECU back in 1993. Like you, I worried about it leaking into the intake manifold--I was having an issue with rich running on startup.

Eventually, I found the safest solution was to replace the entire fuel rail with one from a 1993 or later 240/940 where the cold start valve plumbing was already eliminated. I was never able to locate a fitting which would securely block off the flare-fitting port on the original rail. Do note that the clips that hold the injectors on changed around the same time, so be sure the new rail comes with the newer style clips.

John
--
1989 245 245K / 1993 945 131K

you are over thinking this.

the cold start injector is electrically operated.

leave it where it is.

disconnect the electrical connection from the injector.

place it out of harms way.

drive your car as normally would.

I would like it completely out. That way I never have to worry about it leaking. I'll keep looking for a fitting.

find an acorn nut of the same tpi
these are the sort used on license plates