backfire at top of 1st!

[Litl Sam]

What would be causeing this? It does it very rarly, but scares the crap out of me every time! It is like it doesn't want to shift, so I let off, and then, POW! Maybe it is going to shift and it is just me anticipating it too soon, I don't know. Any thoughts?

 

[Devin]

Mine does that to... just to let you know you're not alone.


I've been told it's that the timing chain is off just a little bit.

Hmmm, ah it won't be long until you find out knowing this board.:tu:

 

[NateLightning]

An exhaust leak can cause it.

 

[sstock]

Guys, are you guys over rich sending fuel into the exhaust? Just a thought.
If your ignition system is breaking down and not hitting everytime, you will send unburned fuel into the exhaust. I would buy good grade spark plugs: Autolites or NGK's make sure they are gapped no wider than .035, run a good grade aftermarket ignition and coil and wires. Especially if your truck is holding on at or right before shift is a good indicator your spark is breaking down at boost.
Steve

 

[Alex R]

Mine did the samething when the fuel regulator was going bad.
changed it and the tucks been fine since then.

Alex