Stumble on initial start

[GrantP]

My 06 lately has started "stumbling" for the lack of a better term on initial start up after it has been sitting a while (overnight). It's a rough idle for a few seconds and some smoke and then it smooths out and runs flawlessly. Never shows up on warm starts. This truck is garaged in Phoenix so this is not a cold temp issue. No codes, fuel filters are fresh. Am I looking at an FCA?

 

[seafish]

You are likely looking at a new FCA.

You CAN diagnose it by adding a pint of 2 stroke or even Marvel Mystery Oil to the fuel tank and then drive it for a little while to run the additive through the fuel system. If the problem goes away on the next start up, you have in fact found your problem -- a sticking FCA.

 

[TCDiesel]

FCA weakest point is Idle, Stumble miss, or loop.

 

[GrantP]

I ordered a new FCA and some other goodies from Geno's. I'll update if that fixes the issue.

 

[GrantP]

I added 3 ounces of two stroke and it still stumbled on startup for a few days. Then I took a road trip and ran it pretty hard and now it doesn't stumble on start. Whether it was the oil or just needed a good run I don't know but I guess I have a spare FCA for now.

 

[TCDiesel]

Put the extra FCA in Plastic Bag with Silica gel bag, its default position is wide open, If its expose to moisture, when its power up it will lock in close position. if the piston get's even a film of rust.

 

[GrantP]

Thanks TC, good to know.