Ok.. recently replace cam,dist,oil pump, timing chain/sprokets. Has been running great, but just noticed what sounds like a small backfire/misfire when down shifting. My thought is that the timing could be just slightly off.. Reset again??

Ok give a better explaination of "down shifting". Do you mean you slow the Jeep with the gears? Or do you mean you hit a grade and need a lower gear? When does the backfire/misfire occur? With foot off of gas? With foot fully depressed? Out the front or out the tailpipe? Is it a 4 or 6 cyl?
Big Jim <img src="/forums/images/graemlins/pfft.gif" alt="" />

1. Slowing the jeep down with gears.
2. Foot off the gas.
3. Tailpipe
4. 4cyl.

First off that is one thing I would NEVER do with a 4 banger.. or for that matter ANY vehicle that was not fully loaded and runing away down a steep slope...
But the tailpipe popping is from unburnt gas outside of the cylinder. Is this happening when the engine is still cold? As if the choke enrichment system is still working? If so that would be normal perhaps. The system keeps the mixture on the rich side and the advance partially retarded until the engine reaches proper temprature.
I doubt the timing setting would be a problem..
Big Jim <img src="/forums/images/graemlins/pfft.gif" alt="" />

Well. it has been extremely cold lately. Guess i'll wait for it to warm up a bit for I make a full diagnosis.

Another question: When engine is first started it acts like it has too much gas.. After it burns off it runs normal. Fuel Pump? Btw.. Fuel Injectors are only 1yr old.

Ralk...my muffler has done that on occasion...not bad, but it's done it. Had a dynomax super turbo on it for a while (bad idea...sounded like rice) which did it much worse. I'm talking about a "gargling" sound, not a "bang" type of misfire.