What to address if I pull the upper intake

[alchemist]

thinking about pulling the upper intake to inspect the all original hoses underneath. What should I service while the intake is off?

Thanks,
RT

[1990LTD]

vacuum hoses...there are a number of them and all in wonderfully different sizes. i'd replace anything rubber, really. you could replace the injector O-rings while you're in there, couldn't hurt.


PCV valve, screen, and rubber grommet at the back of the lower intake manifold



gaskets:

upper plenum to lower intake
throttle body to egr spacer
egr valve
egr spacer to plenum

[johnunit]

the pcv screen is certainly important. It's way down in there, a mesh screen you have to sort of hook out.

[1987cp]

you could replace the injector O-rings while you're in there, couldn't hurt.

Can be quite inconvenient if you break the pintle caps and have as hard a time as I did finding new ones. Then again, I wonder if the caps are quite necessary?

[pantera77]

Can be quite inconvenient if you break the pintle caps and have as hard a time as I did finding new ones. Then again, I wonder if the caps are quite necessary?

Ya, the pintle caps always break on me just pulling the injectors out. RJM Tech has a nice kit for the EV1 and EV6 style injectors that come with all new o-rings, new pintle caps, spacers, and the internal filter screen for like $30.

[alchemist]

Ya, the pintle caps always break on me just pulling the injectors out. RJM Tech has a nice kit for the EV1 and EV6 style injectors that come with all new o-rings, new pintle caps, spacers, and the internal filter screen for like $30.

Actually, its $20 for the EV1 and $25 for the EV6. gotta see which kind i have though. That's a good price.

[gadget73]

if the injectors arent giving you problems, I wouldn't touch them but thats just me. I also lit a car on fire because I sliced one of those O rings once, so I'm slightly disinclined to tinker with the fuel rail if its not neccesary.

+1 on the other things mentioned though, all new vacuum lines, PCV stuff, valve cover gaskets if yours leak, and replace the hoses that go to the EGR cooler in the throttle body. Nobody changes those until they pop. Should be 1/4" or 5/16" fuel hose, can't quite remember right now. if the heater core hoses are old, getting that Z shaped one at the back of the intake out is a lot easier with the upper intake removed.

[GM_Guy]

Valve cover gaskets.

Alex.

[1990LTD]

Valve cover gaskets.

Alex.

DOH!!!! How did I forget those in my list!?!

[1990LTD]

if the injectors arent giving you problems, I wouldn't touch them but thats just me. I also lit a car on fire because I sliced one of those O rings once, so I'm slightly disinclined to tinker with the fuel rail if its not neccesary.

+1 on the other things mentioned though, all new vacuum lines, PCV stuff, valve cover gaskets if yours leak, and replace the hoses that go to the EGR cooler in the throttle body. Nobody changes those until they pop. Should be 1/4" or 5/16" fuel hose, can't quite remember right now. if the heater core hoses are old, getting that Z shaped one at the back of the intake out is a lot easier with the upper intake removed.

1/4" for the egr coolant stuff

[alchemist]

Do most folks stay with the FelPro high temp cork (MSVS50029C) or the Perma-DryPlus design (VS13264T). the latter is more expensive, but I know I used this for an intake on a Chevy Vortec motor and it was far better than the OEM/stock intake manifold gasket.