Intake Plenum on 5VZ-FE

[2TH4IST]

The upper and lower plenum uses MLS multi layer steel gaskets. They are reusable, the felpro is a paper gasket. I have used both and they both work well. The lower lower plenum (ones w/injectors) are a MLS/paper gasket combo. Which love to rust out at the coolant passages w/the ages of these trucks.

 

[Hunter223]

The upper and lower plenum uses MLS multi layer steel gaskets. They are reusable, the felpro is a paper gasket. I have used both and they both work well. The lower lower plenum (ones w/injectors) are a MLS/paper gasket combo. Which love to rust out at the coolant passages w/the ages of these trucks.

So I had the MLS gaskets in there and removed them. I had two separate gaskets removed from the upper plenum (2 halves each) and just a single two piece gasket removed from the lower. I am replacing them because there was a lot of carbon or oil buildup on the plenum around the seams which I’m suspecting due to a slight leak. I also am having some rpm issues at idle which may be due to the leak causing vac issues? Anyway when I removed them the coating seemed to be flaking off so I figured it was time for a replacement set. I just can’t find anything that consistently states there should be two gaskets at the upper interface but it certainly seems to be leaking with just a single one installed. I hope that clarifies things, I’ll probably add another gasket at the upper interface to see if that helps but was hoping someone could confirm if it’s supposed to be there or not.

 

[JustTroItIn]

There should only be a single MLS 2 piece gasket at each location and the part numbers are the same.

Just a moment...

 

[phattyduck]

The gasket is two sides riveted together, similar to an MLS head gasket (those are often 3+ layers). It should look like this:

If it came apart, it is definitely time for a new one. Do NOT use more than one of the correct gasket.

-Charlie

 

[2TH4IST]

These are the exact ones I have on my 5vz right as I type. Replaced them when I did the lower 2 gaskets that were leaking coolant.
When I fixed my friends tacoma w/5vz lower gaskets I used these again on that engine.

If I ever have to do the gaskets again, I'll go oem this time around.

Also as phattyduck/Charlie said, it's a 2 layer MLS riveted together. And never double gasket anything.

 

[Hunter223]

That is exactly what mine look like, only without the coating flaking off. Someone before me must have doubled up for on the gaskets and I just never realized. I suppose I need to go back and confirm that its leaking now with the single gasket in place, although it does sound like its leaking. Assuming it is, what would the recommendation be?

 

[phattyduck]

Assuming it is, what would the recommendation be?

Unless there is a surface finish issue (dings/dents, oxidation), the 5VZ intake plenum upper/lower joints (where this six hole gasket fits) basically never leaks.

There ARE other places where there can be leaks - lower plenum to head, air-assist injectors (maybe swapped for incorrect type?), air assist hoses, other vacuum lines...

-Charlie

 

[ETB2875]

I dunno man, I got the Felpro gaskets and now I''m chasing a vacuum leak :-(