Gas in intake manifold
#11
Who asked for ideas? I'm not the original poster.
The plenum gasket suggestion is a good idea, but for the original poster's question, it solves nothing but possibly the root of a chain of events that may have led to the condition he's experiencing, which is unburnt fuel in the intake.
Okay, so someone suggests to him, fix the plenum gasket and all will be well. BS. The gasket won't leak anymore but he's still driving around with a rich condition. Maybe he still has a cracked guide. A burnt valve. Those things don't get fixed or even diagnosed by changing the plenum gasket.
In effect, telling him it's the plenum gasket means he'll have to tear open the engine twice. Once to fix the plenum gasket, and again to pull the heads for rebuild.
I would rather someone suggest, hey, do a leak down test and a compression test. Suggest, pull the heads and have them rebuilt and checked...and WHILE YOU'RE IN THERE, fix the plenum gasket, which is no doubt leaking and causing problems.
The plenum gasket suggestion is a good idea, but for the original poster's question, it solves nothing but possibly the root of a chain of events that may have led to the condition he's experiencing, which is unburnt fuel in the intake.
Okay, so someone suggests to him, fix the plenum gasket and all will be well. BS. The gasket won't leak anymore but he's still driving around with a rich condition. Maybe he still has a cracked guide. A burnt valve. Those things don't get fixed or even diagnosed by changing the plenum gasket.
In effect, telling him it's the plenum gasket means he'll have to tear open the engine twice. Once to fix the plenum gasket, and again to pull the heads for rebuild.
I would rather someone suggest, hey, do a leak down test and a compression test. Suggest, pull the heads and have them rebuilt and checked...and WHILE YOU'RE IN THERE, fix the plenum gasket, which is no doubt leaking and causing problems.
A blown belly pan gasket causes a lot more problems than excessive oil use. The oil is sucked into the runners which fouls plugs, causes excessive carbon buildup on valves, causes carbon buildup on the O2 sensors and carbon buildup in the cat. All of these are direct contributors to power loss and a rich fuel mixture which cause poor mpg. Your suggestions are well made but IMHO sound excessive and more costly than it should be to correct the 'known to be a very common problem' with the Magnum engines.
#12
My mistake. I stand corrected as to the OP.
A blown belly pan gasket causes a lot more problems than excessive oil use. The oil is sucked into the runners which fouls plugs, causes excessive carbon buildup on valves, causes carbon buildup on the O2 sensors and carbon buildup in the cat. All of these are direct contributors to power loss and a rich fuel mixture which cause poor mpg. Your suggestions are well made but IMHO sound excessive and more costly than it should be to correct the 'known to be a very common problem' with the Magnum engines.
A blown belly pan gasket causes a lot more problems than excessive oil use. The oil is sucked into the runners which fouls plugs, causes excessive carbon buildup on valves, causes carbon buildup on the O2 sensors and carbon buildup in the cat. All of these are direct contributors to power loss and a rich fuel mixture which cause poor mpg. Your suggestions are well made but IMHO sound excessive and more costly than it should be to correct the 'known to be a very common problem' with the Magnum engines.
Don't get me wrong, fixing a plenum gasket is always a good thing to suggest but I want to caution people about, at the very least, hey they propose it as a solution to everything.
Case in point: Post #2 from this thread.
Go to the top of the page and read all about Plenum gasket repairs. You MOST LIKELY have a blown plenum gasket. To fix it RIGHT you need to go to Hughes Engines and get a plenum gasket repair kit. It will fix your problem plus you'll get some MPG back and power too.
It'll fix a root problem of a cause and effect chain that led to whatever issues the OP has right now.
It may not be anything drastic like a cracked guide or burnt valve...it may easier or harder to figure that out but more time and effort needs to be made suggesting ways to find out what IS causing the fuel in the intake.
Those issues need to be identified and fixed, along with the plenum gasket. Fixing the plenum gasket won't magically make the gas dry up and go away with the air flowing through the engine. Something else is causing that problem. Let's focus on that, and then hopefully the plenum gets fixed at the same time.
#14
+2 Sooper, , comp test a simple basic test that can save so many headaches.
Here is a prime example of what you are talking about.
https://dodgeforum.com/forum/2nd-gen...lenum-fix.html
Here is a prime example of what you are talking about.
https://dodgeforum.com/forum/2nd-gen...lenum-fix.html
#15
Hey everybody, OP here. Thanks for all your suggestions. Sorry it took me so long to get back on here, I have been out doing hay. I did some poking around, and discovered that it was oil in the manifold, not gas. I am going to replace the plenum gasket, and perhaps do fuel injectors at the same time. Now somebody mentioned earlier about getting a belly pan, why should I replace it? Just curious.
#16
Hey everybody, OP here. Thanks for all your suggestions. Sorry it took me so long to get back on here, I have been out doing hay. I did some poking around, and discovered that it was oil in the manifold, not gas. I am going to replace the plenum gasket, and perhaps do fuel injectors at the same time. Now somebody mentioned earlier about getting a belly pan, why should I replace it? Just curious.
Is there something wrong with your injectors? They rarely fail, and unless one is failing I wouldn't see a reason to replace them.
The commonly know best fix for the plenum gasket problem is an aluminum pan instead of the steel one that comes on the bottom of the intake. I had been thinking a good fix was just a shorter set of bolts to get a better torque down on the gasket but I discovered my blown gasket already had short bolts.
One of the members here makes aluminum pans to replace the steel ones and sells them on Ebay. There is a really good gasket and bolt kit for $27 plus some shipping and it has almost everything you need to to the project.
Dorman # 615310
http://www.rockauto.com/catalog/moreinfo.php?pk=2194496
Other things I would suggest changing when doing this swap is a set of plugs, wires, cap, and rotor. If you haven't flushed your coolant in a while...which should be done yearly, this is a good opportunity to do that too.
#17
#18
Maybe the misfire is form the O2 sensor running it pig rich due to plenum blown (and can leave stale gass smell in intake). I think I woud try replacing upstream O2 before injectors.. A miss can be caused by more than one thing. And check cat while you are there. It is usually the first casualty form blown plenum.
#19