the miss your talking about,are you sure it is a miss or is the engine surging like its not getting enough fuel or sucking air?
Does the miss or surge go away if you get on it or wind the motor up?
The only thing to do is to start cheacking everything like fuel injectors,fuel pressure regulator,fuel pump,vaccum leaks,voltage to sensors,etc...
Does the truck knock,use oil,or antifreeze?

a sound clip would really help out alot.It doesn't have to be video just sound

 

It keeps missing or whatever it's doing even if I give it some gas. It feels like a lack of air or fuel cause it does it as soon as i start it, and never changes but gets better or worse depending on how hard i drive it. sometimes if i take it to 4000 rpms when i come to a stop it will smooth out to almost perfect and sometimes i take it to 4000 rmps and when stop it feels like its gonna stall. I use between 1 and 2 quarts every 3-4 thousand miles. I'm still on the first oil change, which i did as soon as i got it, about 4000 miles ago. No knocking except for when the egr was not connected...

 

Mason, did you move the wires away from your AC Can, I am not sure who mentioned it, I had the problem with idle and moving the wires away solved the problem, it is related to static charge being created. Another thing to check would be the voltage on your COP's, could be a wire partially making ground as your having the idle problem flucuate which may be from the wire being moved from vibration or from your radiator fan. As well, one more thing to check on is pop off your fuel cap, is there suction noise when removing?

 

No, I didn't do the wires around the a/c but I will - I forgot about that one. How does the cover come off around it? I just don't want to disconnect anything or get shocked. Suction when gas cap is removed? While the engine is running? I've never tried that - should there be suction?

 

Thats one of the first things I told yuh to check- wires around the accumulator - I explained it and posted pictures earlier in this thread..

 

Thanks for the reminder - I'll go back a few pages and find it.

 

Did yuh find it?

 

Ya, I pulled all the wires out of the way and zip tied them so there's nothing within a couple inches or more away from the ac condensor. No change. Reset the battery and everything.

 

Yeah, if you checked everything that was suggested , you most likley have a bad wire short in the harness.

Thats not fun , I have took my harness off before and went thru each wire testing continuity and looking for wires that are bare. When the become bare , they corrode quickly.

The harness unplugs easily so you can just take it out of the truck and test the wires on the bench.

 

Well, I'd do about anything to fix it at this point of money spent and time spent (not wasted at all, I learned a lot). So - how do I get the harness out? Where is it? You make it sound pretty easy - is it and it will just take some time, or is it a real pita?

 

It takes a 10mm socket , just follow the wires the plugs are bolted together.

So all the injectors passed the noid light test? The noid light check is easy and quick - I explained that one already too, I think you did check that right?

If not , noid lights are common and most auto suppliers should have them for 5-10 bucks , there cheap and hook up to your injectors one at a time . It checks the pulses by blinking - watch for one that's blinking funny and that's your bad injector.

 

no i didn't do that check yet. I'll do it and post how it goes. Just a quick side note - what oil do you use/recommend Jbrew? I've gone 4,000 miles on my castrol 5w20 synthetic and need to change it this week. This will only be my 2nd oil change on this truck, and I've already done most of the 100,000 mile maintenance. At least I know it'll run strong for a while - that is once I fix this little idle thing...thanks again for all the time you've spent helping me on this one - I owe you.... well... I don't know what. I'll just say some beer.

 

What ever it says on the oil cap - I believe yours is 5w20 ..

I use Castrol as well - The manual says I'm suppose to use 5w30

I think the 2001 on up is suppose to use 5/20w

I just go by the manual - That's worked for me for the last 220,000 miles - I change the oil every 3000 miles always - I figure thats why I have 220,000 miles on this motor..

My trucks prolly got around 260,000 on it total - new motor in 2000 under warranty..

 

Masonball are ya ever gonna fix it or what???

 

damn ive been reading this thread for an hour and a half.... cause my '01 5.4 is doing almost the same thing.. first it would knock/jump at 50-60 mph in OD.....so a shop rebuilt my rear end, the spider gears had alot of play in them......that did not fix it, so they told me to get a new exhaust system, that didnt work.....they finally replaced a hose and the jumping/knocking stopped...but now it jumps from 300-800RPM while idleing....so im going to drive my truck off a cliff(without me in it) and go buy a bicycle...