Cam sensor is under the distributor cap. The parts stores call it 'the pick-up coil', even though it has nothing to do with ignition.... Holdover from the good ol' days I guess.

Might try unplugging the front O2 sensor, and driving it that way for a while, and see if the miss is any better/worse. It will set a code though....

 

Okay ill try unplugging the o2 just to see. I thought about doing it yesterday. That's wild about the cam sensor I didn't even know, and does the 95 have one also

 

Yep. All the magnum engines have 'em. Same place too.

 

Alrighty. So today the rain let up so I was able to work on my truck afterwards. I bought a brand new quick connect compression tester and a vacuum/fuel pump pressure tester. So I thought maybe I had a vacuum leak but the vacuum tester said everything was good. I was steady at 19 hg. Until the hiss from the iac port started then it dropped from green to red. Then I warmed the truck back up and marked then removed all plug wires and plugs then ignition coil. I ran the compression test dry on all cylinders and then went back and preformed the wet test with a couple squirts of oil. By then the motor had cooled down a little. But ill tell you my numbers for both w for wet d for dry.
1-140d, 110w
2- 85d, 95w
3-140d, 120w
4-115d, 115w
5-95d, 85w
6-85d, 85w
7-70d, 70w
8-80d, 95w
Seems bad. The motor ran fine in the other truck and I never touched the valves except to change valve cover gaskets. It doesn't seem to be pistons by the test but maybe has something to do with valves? I guess ill have to buy a leak down test kit. Any help is appreciated

 

That is bad..... Did you have the throttle cracked wide open? Minimum spec is 100 pounds, and most of yours are below that.

Good news is, it doesn't look like rings are the problem, you could probably put new heads on it, and solve most of the issues.....

 

Yeah I had the trottle wide open. No matter what its bad but I hoping its not the valves and just head gaskets. I bought the leak down tester so ill do that after work. Yee haw

 

I doubt its head gaskets...... Likely cracked valve seats, and assorted trouble. Might try running a can of seafoam thru it via the brake booster vacuum line, and see if the numbers change at all.

 

I did the heads on mine when I got it. I had the usual cracks:

5.9 stock head cracks.


Steam actually chipped the valve when it broke out as the head cracked.

The real story though, is that the chambers that weren't steam cracked almost all had valves that were leaky garbage and ready to be replaced. This engine had high miles, but it'd been leaking for a while at the seats.
At least if it's the valves you can pull them, replace the valves, and try to lap them in, which is easy with the stainless seats.
Given the data from the comp test, I think that's kind of the direction I'd go.

 

I checked in on this thread because I have the same vibe as the OP. I get into 4th and it'll vibrate, then it'll cease just before it goes into kickdown as I press the throttle. But lugging along, I get that janky vibration.
I need to reroute my wires and replace my IAC (I've cleaned it). But I have great compression now that I have those EQ heads on there.
I'm going to keep at it and try to see what resolves it.