truck feels like its missing???? COP's
 

Ok ,heres what I've got. A 2001 4.6, recently purchased. Changed plugs and fuel filter and it run real good. Very high miles. I switched the C.O.P.s out and put them in my 2002 with a 5.4. i did loosen up the fuel rail on the drivers side. Also removed all the wires on the cop's and fuel injectors at the same time.
I cleaned up the cop's from the high milage truck and sprayed with silicone.Then installed them in the 2002. Put it all back together and now it doesn't run quite right. It feels like it is missing. I don't have a check engine light on. Could something be going on with the injectors? The cop's worked fine in the other truck(the 2001).
At the present time the 2001 is in the driveway without the cop's for right now.
I don't think I mixed up any wires on the injectors, but I'm beginning to wonder. Could I have missed something on the fuel rail?
Thanks for any input. I'll check back tomarrow, bullseye670.....

I have experience with this type of missing.
Something in what you done has caused a marginal situation at the plugs.
It could be the boots are allowing leakage.
The different COPs could have a different winding resistance.
You will have to sort it out by trying new boots and sealing them well with dielectric grease. Don't use any sprays that are not specifically for the purpose.
Once break-down has occurred you can never be sure that carbon tracks and pin holes are not present on the old boots.
Some will blame plugs for this and it may indeed be part of the problem but the bottom line is you don't know what it is unless you replace all the boots, maybe the plugs or even put the original coils back in.
Just a hint on why there is no code set.
The seeming miss is so random that the computer cannot ID a specific reason and therefore can't set specific code/s.
All the parts can't suddenly be bad unless something was done to them.
What I think is happening is there are leakage faults who's effects get reflected back to the computer and interferes with signal processing such that almost any engine reaction can result depending on what routine is affected at that instant. That may be what you percieve as a miss without supporting code.
This is not set in stone but an attempt at educated analysis of the possibility why there are mysteries about this engine design using 'deep well' ignition and being so touchy.

I am in the middle of an investigation right now. I cleared my fault and in a waiting period to see if it holds up. Then I may have quite a bit to say about this failure type that will be a surprise to some reguarding spark plugs and the whole system.
Your the first to hear about this because you discribe your problem as very simular.
Good luck and let us know what you had to do to clear the fault.

FYI, just because the CEL is not lit does not mean that the OBDII systems is not storing codes. The CEL will only illuminate after a sensor is more than 150% out of range. You could have a miss just not one that is bad enough to trigger the CEL. I would check for codes to be sure.

Very interesting. I think I'll check the codes this evening and see if anythings showing.Perhaps this could pinpoint the cop. The miss is somewhat minor but somthing is definitly wrong.
I'm also going to check the resistance on them tonight. I have a set of known good coils that originall came on this truck. It ran perfect before the swap out I'm also gonna look at getting a new set of boots. These cops have 195,00 miles on them. I can see that one has been replaced with a "newer" one. I see the salvage yard yellow marker on it
Thanks, will keep this posted.
Still kinda wondering if the fuel injection could somehow be causing this???
I've done cops on the 4.6 with no troubles but did not remove the rail.
bullseye670...........

how do u know its missing? is it not in the driveway anymore

That silicon spray may have screwed up one of your coils - U really didn't use that stuff did you?

lol

Ok, everything is great now. I messed up. "somehow" I missed the plug on the cop on no. 4 cyl. Glad I checked evrything before I started ripping them all out. Thanks for all the input into my self made problem.
Now I'm gonna continue on my newest truck. I got a great deal on a 2001 flareside lariet Supercab 4x4. Its in excellent condition. Maybe even better than excellent. Only thing is its got 195 k miles on it. Company gave its rep. $30K to go buy a vehicle and this was it. He cranked up the miles and then the company let him keep the truck. Its sat in his driveway for the last 6 months.
It started right up. After a new fuel filter it runs great. Not a bad find for $5000.
thanks again for the help, bullseye670...........

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