This should give you a idea what you will be looking at.

 

Nice pic, good add, thanks! So new symptoms..loss of coolant and a slight smell of coolant..And it doesn't happen every time but I've heard a tapping when I shut the engine off..lasts just a few seconds..oddness...

 

I'm going to retest tomorrow..not sure of these results..CEL is on & code is #8 misfire P0308...I did all 4 cylinders 3x and the strange thing was #6 started at 150 then 160, 165, then 120 & 120???
Dry test results:
#2-170
#4-170
#6-120
#8-140

Did an oil change was very dark w/no antifreeze..all five qts were there so, plenum repair worked. But, when I went to take the filter off NOTHING dripped down and very little in the filter. First time I ever used that type of filter..anti drain back valve maybe? Guess I'll find out on the next change. Still have a low curb idle reading tho.
I do have a new FI I might install..I'm still leaning towards the #8 FI being bad and the HG being blown..But I will do the dry/wet comp tests just to be sure before I tear it apart! Any thoughts advice.

 

Did seafoam again, this time via the vac line almost no smoke at all..retested the compression with the same results..Replaced the #8 FI didn't fix the shutter issues..So I think I'm looking at the head gasket or transmission/torque converter causing the shutter. And the oil pump causing the low curb idle issue?? O btw, I did replace the passenger side hub assemble, so at least something is fixed

 

Did you ever route your plug wires per the TSB?

 

Your numbers are too far apart...... biggest difference allowed is, all cylinders should be within 25% of each other, yours are not..... I would check and see if you have the six, and eight plug wires crossed......

 

dodge dude94, HeyYou, I checked their route last week, I can check again today. I thought there should only be a 10% difference at most. But yeah way to far off. Would 6 & 8 be much lower if it was the head gasket? And cross-firing wires can cause low compression??

 

cross-firing won't cause low compression, that's purely mechanical.

You have something going on there.... a leakdown test would tell you where the compression was going. (valves, or rings....)

 

Sorry I misunderstood you guys with the whole wire routing/crossed wire stuff..Like I said I'll check the wires again and will do leak down test too..I am questioning that test tho, because if the valves, seats, cylinders, rings are ok how would I know? Because if the dry results stays the same it means it's a valve thing. If the reading goes up it's a cylinder or ring problem. Would the readings go down if it's the H gasket?

 

6-Truck in gear, stopped with foot on break, once break ped released truck shutters
7-Stops once gas is applied

My truck -Details in my header; is doing the same exact thing; except I have very rare misfire on number 7 .

I've done:

Tune up about 3 times, plugs; coil; plug wire; tsb routing (and then some) TPS;MAP; Cleaned the TB; Coolant change; only thing on that i noticed was in my resivor tank looked like old clumpy Chocolate milk. kinda a rust color if you will.. was like gunk.. in the bottom..

No coolant loss i know of.. cant say if she burns Oil; I dont think so other than what pulls through the PCV and crank case filter; as she has a few leaks here and there..

She does get the random check gauge; no oil pressure problem that is common on these trucks;

Tensionor; Belt; Idler; checked for any other worn out pullies; various testing to seal off VAC lines to see if it was a problem with one of them.. and various otherthings..

Put some lucas through the tyranny no difference; tranny shop said the TC was fine..

Reverse stall RPM will not go any higher than 2000 RPM Floored..

and at this point i forget what else ive done.

I know i need Engine mounts; that might be part of it.. but there is def. a gremlin in the motor.

Seems mechanical of nature (something messing with the timing/firing..

I'm down to injectors; (THinking of power flush the system) timing chain/sprockets. Valves, springs; push rods; cam lobe warm or something like that..


I hope that you find and fix the issue; and I hope it's something cheap and easy.