So i replaced my plenum plate with an aluminum one from Hughes.
I didnt knowtice a huge change but the peace of mind is nice too.

Heres some pics:

Before





After

 

It's not a performance mod, but a needed mod non-the-less...I have plate I need to put on too.

I hate mods that don't add a little HP as well.

 

Couldn't it add HP back that you've lost from the leaking plenum? If that's the case, you could always look at it like you've simply brought your truck back to a better state! =)

 

What was all that crap inside your intake? At first I thought it was a really lousy casting, but then I saw the after pic.

 

its oil. thats what happes when you have a blow plenum gasket.

 

Actually looks fairly clean to me, almost like the plenum wasn't leaking. Some soot is normal. The gasket looks like brand new too.

Congrats on the new install, though. Always feels good to tackle a project like that... even if you don't gain HP or make the truck run a lot better.

 

I like the idea of marking down that torque pattern, I'll be using that when I yank the plenum here in a few months. It's the little things that make this job easier, lol.

 

Did you do a tune-up after you finished the plenum job? It is not merely the presence of oil in the plenum that causes performance and mpg losses, it is what the oil does when it fouls your plugs, cat, etc.... If you suspect you had a leaky plenum, and you fixed it, that should be followed immediatly by new plugs and a general tune-up. Otherwise, you are still driving around with all the same problems the original blown plenum caused. It won't get worse since you fixed it, but it won't get any better because you fixed it either, until you do this other tune-up.

 

I did half of one. I didnt have enough money to buy the O2 sennsor but i did change the cap and rotor while i was back there.

By the way, there is only 2 o2 sensors on our trucks post 96 right? OBD 2, one pre cat and one after...

The guy at the parts store keeps telling me that there are 3. One on either side, after the exhaust manifolds, and then one after the cat. Im pretty sure thats wrong and i was under there looking yesterday when i did the starter.

Another thing too, he also says that if you don't have a cat, like me, that your 2nd o2 sensor really dosnt do anything so i shouldnt have to worry. Could that be another reason why my milage is the pits?
I dont have any check engine lights the only warnings that are showing are (ABS) and ((P)(!)), But funny story the
"Yellow ABS Light" relay under the hood was removed so the light wouldnt be on, is there a check engine light relay?????

 

The ABS relay is for the 4wal verison. If the parking brake lite is on as well, that is probably why the abs light is on. (or, the sensor in the rear diff is toast.)

You only have two O2 sensors. (unless you have california emissions, which seems highly unlikely....)

Post cat O2 monitors catalyst efficiency. The PCM will set a code if it doesn't see the right readings from it, but, it won't affect how your truck runs regardless.

Bad O2 sensor will give you crappy mileage. (as will a host of other things....)