I second both onemore94dak and ZEN357 - do all that onemore94dak says, then replace the O2 sensor. Use an OEM sensor (Mopar or NTK/NGK); avoid Bosch.

That much on the bottom of the plenum means the O2 sensor is also plugged and working sluggish if at all.

RwP

 

In all reality, you don't really need the aluminum plate, though, it IS good insurance. The major issue is the bolts are too long, or, looking at it another way, the gasket was too thin. You *can* just replace the gasket, but, if you do it that way, trim the unthreaded 'nubs' off the ends of the bolts, or, get new, SHORTER bolts. Follow the correct torque sequence, and don't forget the lok-tite. You will be good to go.

The whole 'gasket blows to to different expansion rates of the metals involve' is a myth. I did the math, and the difference in movement is measure in ten-thousandths of an inch. That ain't the problem.

 

HeyYou, Are you saying the plenum plate bolts were OE too long and that prevented it from being tightened enough to let the gasket hold?

 

Correct. When the gasket was NEW, they could torque the bolts, and it would actually seal. However, as it aged, the cork hardened, and blew out. Fel Pro gasket is multi-layer paper/whathaveyou, and is much better quality than stock. The bolt holes in the intake manifold are not deep enough to get a proper torque on the gasket though. Cutting the nubs off, or just getting shorter bolts solves the issue. (with a good quality gasket. )

 

I never would have thought of that. Thanks

 

For the new shorter bolts, will they sell these at home Depot or something? What size are they do you know?

 

Just take one of the old ones with you, and have them match it up. (just shorter.....) Lowes, Home Depot, or pretty much any hardware store should be able to set you up.

 

hey, so I'm at oreillys and autozone but they don't have a plenum gasket, just intake manifold gaskets. I'm assuming thats the same thing but wanted to double check before I commit. all the pics they have on there vary so much its inconsistent to what I'm seeing at third party vendors.

 

The plenum gasket is separate from the intake gasket.
This is the plenum gasket. It might be slightly different for your rig.
https://www.autozone.com/external-en...t/dodge/dakota

This looks like a kit with the plenum and the intake gaskets. You'll have to replace them all anyway.
https://www.autozone.com/external-en...7_825018_12080

 

You need the rest of the intake set to change the plenum gasket in any event.