So finally after a seven month rebuild, i was able to start my 3.4 last week. In June I spun a bearing after driving around with a misfire for awhile (injector believed to be the culprit). I took the engine out and rebuilt it replacing just about everything. I also had a valve grind done after my heads failed a vacuum test miserable. I opted to do the valve adjustment myself thinking it'd save some money. Turned out to save 10 bucks. I'm pretty sure I did the adjustment right because I've done it on dirt bikes before. With that said, i cant be 100% sure.

Once I put the engine back into the truck I had a few bugs to work out. Its been mostly simple stuff fixing oil and coolant leaks by tightening down bolts I over looked. After some fuses and a new starter, I got the truck to start. which brings me to where I am now.

I can only seem to start the truck if i feather the gas just right. once its going, I have to make sure to keep it around 1500 RPMs or it'll die. I was fortunate enough to run it long enough to get a CEL. The codes that came back were p300-p306. So my first question is here, is every cylinder misfiring, or is the computer just having a hard time narrowing it down to one or two?

And my second question is whats causing this!? So far I've checked the IAC and TPS. I've also cleaned the MAF and double checked my timing. Today I'll try to check out the o2 sensors to see if that's the problem. It seems to me that is not a coil, plug, or wire if its happening to all 6...It'd almost have to be something that affects all of the cylinders. But I really don't know. Ideas?

 

what kind of spark plugs and wires did you use? if your answer isnt NGK or DENSO, that might be your problem.

 

The plug wires are OEM and the plugs are NGK v-power that came in my rebuild kit. They are single ground electrodes...Something I've been wondering about. When I bought the truck, they had single grounds and worked just fine. When I got my original misfire, I went and got some new plugs. Autozone gave me single grounds... So i took them back and got some dual grounds. It didn't make any difference that I could notice. So when my kit came with single grounds I figured it'd be fine. What are the odds this is my problem? I'm $2000 into this project and really don't want to put more money into it if its going to be useless

 

i would get the duel grounded plugs. try the NGK BKR5EKB-11 or DENSO K16TR11.. see if that helps, its the cheapest way to make sure its not the plugs..

single ground plugs kill babies when pared up with the 5vzfe.. good luck.