So why won't it show a small leak?

 

I have no pooling oil, just some dark looking film near the breather port. I did the same vacuum test and it showed a few lbs pressure on the gauge before I disconnected it. I'm feeling pretty good that the gasket is still intact.

I may be the only one with an original plenum still sealed tight. Let's see how long that lasts....

 

If the leak is minimal, the oil itself, is sealing the leak as it get's sucked through the gasket. Just my theory, but I've taken enough Magnum intake's off to know, that test is waste of time.

 

I am going to continue to monitor my engine for any signs of the blown plenum gasket. I have a benchmark for the test and I have my fuel log so I should be able to observe any changes pretty quickly.

I have a spare plenum on hand that I am going to clean up and replace the gasket.

I keep forgetting that the actual mileage of my engine is unknown. Supposedly the engine was replaced by Dodge around the 50k mark.

 

Just be aware that even a small leak is going to slowly ruin the cat.

 

Hey, I'm gonna give a shout out to my boy zman here. I too did the tsb test and had positive pressure. I too argued that the plenum was good. I got tired of worrying about the plenum, got a hughes kit, and took a day off work. When I looked at the plenum gasket after removing the manifold, it was poking out between the bolts. Not totally displaced, but it had to be leaking some. Not leaking enough to fail the tsb test, cause massive oil consumption (was getting worse), or cause pinging. Now that its replaced, I do notice a bit more low end power and it idles better. Only 100 percent positive test in my mind is to pull the intake. Not trying to freak the op out. I'd just rather change the plenum gasket than keep monitoring it indefinitely, personally.

 

OK, you convinced me. I'll crack that egg in the next few months. I'll let you know what I find. (Something tells me you guys know what you are talking about!)

 

Even if it's not blown, it will be eventually. If you fix it now, it's one less thing to worry about.

 

I'm certifiably crazy I know, but I've been under the impression/assumption that Dodge did something (other than the 'flash') to address the issue in '01-'02.. shorter bolts? dunno.. I've read in other forums and heard directly from Dodge mechanics that this is so.. but sometimes, folks blow hot air- sorta like what I'm doing now..

Obviously, I went ahead and put a thicker aluminum plate on the thing and called it a day- because no matter what we KNOW it's a weak point..

 

I don't know if they did anything about the bolt's, but I do know they(dodge) make's an upgraded gasket, compared to the original.