As you can see in the a/f readout, the truck leans out after about 5k RPM. The tuner said he has no control of fuel after about 4500RPM and that the truck didnt seem to be responding to timing changes. Does anyone have any Idea on what the problem is. He[the local tuner] and Sal are working together to try and figure out what the problem is but if anyone has any ideas that would be greatly appreciated.

This issue is making me and

 

What was the timing? Have you pulled any plugs out to look at them? Are you still running the stock blower? I remember you were planning to upgrade it. Is your fuel system up to the task of supply your new motor? Looks like funny graph lines. All wavy.

 

And your exhaust back pressure is ????

 

Silver Bolt hit it on the head, I got the same answers.
Change the Fuel Filter and Plugs, and Re-Dyno it.
When mine got weird and leaned out one side melting 3 plugs in a row, I called BFB and Hooters and they had me pull the filter and cut it in half finding out it was a fuel problem sending it lean.

I also agree with Bolt that the Graph is not smooth and consistant and appears to show in and out power + torque, maybe off and on would be a better way of saying it. You can see how it clearly goes up and down in both cases ???

 

Yeah, maybe plugs or fuel. Once the truck hits 3.6k it starts the ocean effect. When's the last time you changed your fuel filter, changed plugs, etc.

 

there are 10500 miles on the truck and I have not yet changed my fuel filter. I said to the tuner that most people say to change your fuel filter every 10k miles and I have not changed it since it was new. He said that the filter is unlikely the problem and if it was the filter [frogot what he said exactly but basically if it was the filter the graph wouldnt look like that]

 

What plugs with what pulley setup???

 

My filter looked like this at a little over 5000 miles on my 02


It did this


I changed the filter and plugs, decided to take off my Upper Pulley for the winter, then made one last run for the year without my upper pulley a week later and it did this


IT SEEMED TO BE MY PROBLEM
Got two thousand miles since and it's running like a top

 

well tomorrow im going to see if i can change my filter...i think i might go to the auto supply store tonight.