Recently started idling ruff with loss of power

First was it doing that before you changed the timing chain and second I have a 2005 Ford escape that was doing the same.I found some vacuum lines that had some small cracks in them so check all the vacuum lines and see if that helps.Good luck

What about the coil packs? Do you have a check engine light on? If so take it to an auto parts store and see if they will scan your vehicle for the codes.

The naturally balanced configuration virtually eliminates shake and idle roll. The standard Vortec 4200 engine delivers the most horsepower in its segment - 275 hp with 275 lb.-ft. of torque for strong trailer towing capacity.---------------------------------------------------------------------------------------------
Audi-VW Airbag Reseter

The oder and loss of power and poor running is do to a failed catalytic converter.

I Have a 1999 ford f150 4.6 that back fires and is just running really ruff when idling alot of nack fire a sord of like a pulse going on what is my problem?

fuel lines inside the intake plhenum may be cracked and leaking inside the plhenum. same thing happened to my 1992.sonoma. they are made of a plastic material and tend to crack right in the bend of these lines.

check inj thay do click but not very load but becuase it might be it damaged it is doing this

it might be your fuel pressure regulator. it its a vortec 4.3 i had to change my regulator twice.

replace your MAP sensor(manifold absolute pressure) the map sensor is the computer for your fuel pressure regulator telling how much pressure. Unless your tahoe runs like **** going up hill than it inevitably your fuel pump

clean out the carb and fit an inline fuel filter between the pump and the carb .