I'm doing the L98 intake job and I've found that my cold start injector
has been leaking.
Any one here know if fel-pro has a part # on these o-rings?

 

If the injector is leaking fuel send it to Rich at CruzinPerformance for reconditioning (link on my site).

If the mounting is leaking air, verify that the flange is straight; if so try some grease on the O-ring.

If FelPro doesn't sell it, you might try a hardware store.

 

Are you referring to the large O-ring on the cold start injector itself or the small one on the opposite end that goes into the fuel rail? You can either buy what is called a "tube kit" from GM that has all of the fuel rail O-rings and the two tubes which go between the rails or try to round one up at a hardware store or supply company. I needed just the small one that goes into the fuel rail and couldn't find one that would seal properly at a hardware store because it is a pretty thick O-ring for as small as it is. I finally found one at a specialty supply store here in Phoenix, but I don't remember the name.

 

Try a store that sells hydraulic equipment. They usually have every o-ring under the sun, or can at least order one for you if you have the old one handy for measurements. :cheers:

 

corvette_bob,

Vetracer is correct, GM had a cold start o-ring kit to replace the top and bottom o-rings on the cold-start injector itself and the cold-start feed line. It's a 3 o-ring kit. It's shown in the parts books under the section for
1985-1991 Y FUEL INJECTOR RAIL MPFI (MODELS F8A,R810) (L98/5.7-8)
Ask for:
GROUP 3.329 O-RINGG KIT, COLD START VLV (INCLS #102, 103, 104)