I did'nt touch the ground, but I'll check it though. Yea, It was running fine with no codes at all. After I did the tune up I started getting the codes. Misfire on #2 and #5. I have cleared the codes several times, and I the same one's keep popping back up. The truck runs fine.

 

how are the spark plug threads in the heads? Do the plugs come out easy? Maybe its possible that your not getting a good ground connection with the spark plugs....

 

The plugs felt normal when coming out and going back in. I'm going to take back to the stealership this week. Larry going to see if one of his master techs can track it down. This has got him stumped as well. I can tell you that it don't seem like it has the get up and go since I put the OEM wires in it. It may just be my imagination, but I think it ran better with the NGK wires in it. I played wiyh all the connectors while it was running, never did notice a miss. If I ever get this figured out ya'll will be the first to know. I really appreciate all the suggestions.

 

any updates ?

 

I took my truck back to the stealership yesterday. The tech he had messing with it determined that the misfire was not electrical. On the scanner everything looked fine. The timing advance , injector preasure ect. Her pinched the fuel return line off to see what it would do. He recomended a BG injuctor cleaning. There goes another $140. After this was done the codes were still coming up. Another tech came over and got to thinking about this whole orrdeal. He decided to pull the timing belt cover off and checked the timing marks. It was off one tooth. I'm suppose to go in and pick up my truck today. We'll see if that was the prob. It still don't make any sense to me what a tune has to do with it. But, if it fixes the problem, great. I'll let ya'll know later today if this was the prob. Thanks.

 

The timing belt being off can definately cause misfires......I hope it was that simple.

 

I do to. It sure has been frustrating though. I'll find out here in a little while. I now have 2 extra set of plugs and a set of wires laying in the garage. With close to 175,000 miles on it. It is still a great truck.

 

that would be awsome if it fixed it but why would it only misfire on those two cylinders?

 

Keep us informed please! I have cyl #3 miss-fire.

 

I called the stealership yesterday before I went to pick up my truck. Just to make sure it was ready and I did'nt make a trip into town for nothing. It's a good thing too. They were thinking the tensioner could be bad, which is why may have been why it jumped time. After he got it apart he noticed that the wedge that goes somewhere around the cam gear had come loose. I don't know a whole lot about that part myself. I had to wait for the parts to come in this mornig. He had to order another gear. It did'nt change the price he was going to charge for replacing the tensioner. It is suppose to be ready around noon. I'll let ya'll know how it all turns out.

Hey Hopper,
On your misfire. The tech was able to tell me if it was electrical or not by using the scanner he had there at the stealership. They did'nt charge my for that. If you know someone that works there you might be able to get them to narrow it down for you. I wish we would have done that right from the get go. It would have saved me a lot of time and money. At first he though maybe a fuel prob. But it turned out to be the timing. I'm hoping that solves it anyway. Good luck on your adventure. Tommy

 

I hope your misfire is not from the crank pulley not being tightened enough (and that the pulley didn't damage the crankshaft......not worth going into unless they come back with that as the diagnosis). If it is just the tensioner being bad, that should be a pretty easy and fairly low cost fix for you (should be less than $400 for sure including a new timing belt, idler and tensioner). If it was the tensioner as he was saying then the timing should have been jumping around all over the place on the scan tool when you give it any gas. Keep us informed as things progress.

 

Ok, I went and picked up my truck today. This is what they did while they had it. The tensioner, timing belt, crank timing gear, crankshaft pulley were all replaced. I also had the BG fuel injector sevice done. I just thought my truck was running good. It runs great now. He told me the tensioner might have got stuck or something at one time or another. That caused it to jump time. I'm assuming when this happened it caused the wood ruff key to come out. Well, whatever caused the problem was, I'm glad to have it fixed. I did'nt like spending the money, but I did'nt think $500 was to bad for all they did. Larry cut me some slack on the bill. I have to say that Yotatech Rocks. I don't post much, but I do spend alot of time reading. I have learned alot about my truck on here. Thanks for all the help. Tommy

 

good to hear its fixed amazing how that all happen after a simple tuneup

 

Yea, It don't make any sense to me. May have been ongoing prob. for a while and I just woke up the beast. I do know this thing runs great now. It don't down shift out of overdrive on some of the hills that it use to. It may have been the BG service. I don't know. I won't complain.

 

Glad you got it fixed and all is working well again.

 

Yea, Me too. A big relief. Again, Thanks for all the suggestions.

 

Verdict: NGK plugs and plugwires or OEM Densos? I have the 1996 3.4L V6... Im about to use Elton and others previous posts and put together a laundry list of major tune up items including Seafoam, etc... so will need to replace the plugs and plugwires. (Also have recently gotten misfire code for 5, but hasnt come on since...prob time to change them)

 

both ngk and denso are great its up to you

 

I'm guessing either plug or plug wire will work fine. They were'nt the culprit of my problem. I'll put the iridiums in the next time I change my plugs. All is well till then.