im having a problem with my tune. when i go wot from a stop my pulse width B0721 skyrockets up to 4407ms when according to my tune i should only be getting 2201ms. it takes about 1 second for the pulse width spike to come back down to where it is commanded to, and it never does this again in my logs except from a stop.

what can i do guys?

With out looking at your tune, I would have to say what you are saying is normal. Look at your Main Pulse Injection table at 90-100 MM3. When you punch it the rail pressure can't rise that fast, so it's going to hang to the left side of the table until rail pressure rises. As rail pressure rises the pulse width will shorten. I bet that is what is happening, but with out seeing your tune or log, I can't guarantee that that's the problem.

is that actually a problem then? Does it matter?

The pulsewidth run by the truck is determined by the actual fuel rail pressure. If your truck is losing rail pressure due to a sup-par condition in the fuel system then it's possible for pulsewidth to run off of the cells in the lower left.

The cure for this is to freshen up filters and make sure lift pumps are operational, or to shorten up the pulsewidth in the bottom rows so that the load on the system better matches the system's ability. I sent you a tune to hopefully cure the issue on your existing fuel system. :)

Hope this helps,

Nick

As Nick said, the pulse is based on actual pressure, which is impossible to maintain in stock trucks. It can result in high EGT's, what I call "classified". This is because the additional pulse is on the same timing schedule as the shorter one, and this leads to excess combustion post TDC. IOW, burning the exhaust tract.

Stock trucks should be limited to around 2400 us for this reason.

first off let me tip my hat to nick for his excellent help with efi:) thanks nick.
i will try the new tune when i get back from mexico:D.

i will change both my fuel filters just to be certain.