Plenum DIY

[ramthis9501]

Here is a full DIY on a plenum plate and gasket repair for a 2001 Dodge Ram. Disclaimer: I nor SEM are responsible for anything you do to your truck. This is strictly a DIY, no one is responsible for what you do. I will be adding on to this as we do things, should be done in 2 days. Here we go:

First off, take off the intake or air breather box, whichever you have.


Next: disconnect battery (should've done it first...)


Then remove the wiper fluid and coolant boxes along with the fan shroud and radiator. 4 bolts for the shroud and 2 for radiator.



Next take the drive belt loose



Then remove 4 bolts for A/C compressor (pic is after it's removed) And take loose two connectors off of it. A bracket will come out with it, it sits on top of the compressor.


Move compressor to the passenger side fender


Next remove the altenator (2 bolts) and 2 connecters


After that remove the accessory bracket (5 bolts) one bolt is underneath a pully. Just remove the pulley and you can get to it easily.


Then remove the heater hose and coolant hose. The coolant hose goes to the thermostat.


Next remove the injector lines


Last thing we did tonight was remove the throttle cables


Will start back on it tomorrow and I'll be taking more pics all along the way so stay tuned

[Smitty]

Being a diesel owner...what is the plenum mod/DIY do?

[ramthis9501]

The plenum plate sits underneath the intake manifold, and it has a gasket that sits between it and the manifold. Dodge messed up by putting a cast iron plate under an aluminum intake. Well in the winter, the temps fluctiate so much between the two metals that the gasket eventually ruptures and lets oil leak through into the manifold. In time it causes power loss and other problems. The best way to tell if your plenum is blown is to look down the throttle body and if their is oil pooling then you got a blown plenum. The fix is a new ALUMINUM plate to put in place of the old cast iron one so that the gasket will stay in place and not rupture. In terms it gives you better fuel mileage, performance, and takes away the potential of your engine blowing up.

[Smitty]

Ahhh. Thanks.

[BAD HABIT]

I still have my steel plenum from my 99, eeeww was that bad....

Sent from my badass EVO on TapaTalk....

[RamSport97]

Originally Posted by ramthis9501 The plenum plate sits underneath the intake manifold, and it has a gasket that sits between it and the manifold. Dodge messed up by putting a cast iron plate under an aluminum intake. Well in the winter, the temps fluctiate so much between the two metals that the gasket eventually ruptures and lets oil leak through into the manifold. In time it causes power loss and other problems. The best way to tell if your plenum is blown is to look down the throttle body and if their is oil pooling then you got a blown plenum. The fix is a new ALUMINUM plate to put in place of the old cast iron one so that the gasket will stay in place and not rupture. In terms it gives you better fuel mileage, performance, and takes away the potential of your engine blowing up.

You definitely got the gist of it. It's not a cast iron plate, its just a stamped steel plate from the factory. The aluminum plate will expand and contract at the same temperatures as the cast aluminum manifold will. This helps preserve the life of the gasket in between the plate and manifold. The aluminum plate is also thicker compared to the factory plate so the bolts will not bottom out and can be torqued down correctly and completley. Having a blown plenum gasket doesn't necessarily mean you are going to blow up your engine. My truck had a blown plenum for nearly 12 years. However you are right in that it will reduce oil consumption, minor detonation, and it will help with fuel mileage and performance a little.

For those that have not done the plenum fix, and are experiencing the symptoms, filling up with premium will eliminate any detonation problems. However, eventually the spark plugs will foul out, usually starting with cylinder 8, causing some severe misfires.



Looks good so far Colton! Keep the pics coming.

By the way, you didn't have to remove the radiator shroud, but it sure gives you gobs more room huh?

[FL06SRT10]

If your going that far replace the intake manifold with the mopar performance 2bbl manifold if it's still available

[ramthis9501]

Continuing on...

The only thing other than the bolts holding down the manifold is the fuel rail. Going to either have to get a fuel rail removel tool or a quick disconnect tool like shown in the pic. We used a 3/8" disconnect and it came right off.




Remove the bypass intake coolant hose. It's a good idea to replace that as well.


Now it's time to pull the bolts from the intake. There are 12 of them, remove every single one of them and hopefully if you bought new bolts as replacements, then throw the old ones aside. Shouldn't use the old ones anyway because you won't be able to torque them down to specs.


Before you pull of the manifold, pull the 4 bolts and take off the throttle body. You want to get that out of the way so it won't get screwed up. It'll look like the pic below when you do it.


Now pull the intake manifold from the engine. When you do this is what you'll see.


And here is the bottom side of it, the dark thing is the plenum plate. Pic below that is the inside of the plenum plate, notice the oil pooling.



Now you can go two ways, do what we did and pull the valve covers and replace those gaskets as well or don't. Your choice. Here's what it looks like underneath there.


Take the valve covers and intake manifold outside and clean them. I used engine degreaser, dish soap, a toothbrush and water to clean them. Make sure you get as much oil out of the intake as you can.



Here are the new valve cover gaskets.


Now time to put on the new aluminum plate and gasket. DO NOT use any gasket sealer on the plenum gasket. Use the NEW bolts that came with the kit. There are 15 of them. Use blue thread lock on them.





Now put the valve covers back on. You don't need to put any gasket sealer on it.

Here's what it looks like down the holes on the manifold. Notice the shiny aluminum


Now put on the new manifold gaskets. Use black rtv gasket sealer where the ends meet on the gaskets.


Time to put the manifold back on. Bolt the throttle body back on as well


Bolt it down with the NEW bolts that came with the kit. There are 12 of these.

Then put the fuel rail back on. Be careful putting it back in.

Put the thermostat back, I, along with many others reccommend to put a 180 tstat in place of the 195. I did and it is worth the $6 to have your truck run a little cooler.

Put the accessory bracket back along with the altenator, a/c compressor and all the connectors that go with them.

Put the throttle cables back in place.

Attach all vacuum lines and connectors that are still free.

Put the radiator and fan shroud back on.

Attach all the hoses back. Refill the radiator with new coolant. Put back the coolant bottle and wiper fluid bottle on the shroud.

Put the breather back on the throttle body.

Make sure everything is back where it went and you should be good!

And here is a vid of when we first started it back up. Notice that there is no air leak. It was LOUD before and now it is smooth


And here mine is all put back together!



Anyone needing help with this or have any questions just shoot me a pm and I'll see what I can do.

Thanks to all for the help and advice along the way with this project!

Hope everyone enjoyed my Plenum Repair DIY

[ramthis9501]

And let me add that my plenum gasket was pretty much gone, not much left of it lol

[Onk]

Colton,

Very nice write up!!! Very thorough and detail oriented.

This will certainly be useful down the road to many members!!!