Bogging, stuttering, backfiring when gas pedal is pushed. Help Please

[jascolt]

Hello all. I am new to 4runner section, spend most of my time in the 60 section but my wife's 99 4runner is having issues. Sometimes (usually after starting hot or cold) when in gear and the gas pedal is pushed the engine seems to bog down and sputters and will usually backfire and not accelerate. Sometimes it gets better when it warms up and sometimes it doesn't almost as if temperature has no effect on it. Sometimes if your at a stop sign and pull out it may bog on you and sputter out into the road--not really the safest situation if a car is coming.
Things I did:
New plugs
Cleaned coil pack contacts
New air filter
Cleaned MAF sensor
New fuel filter

Code showed misfiring on cylinder 3 before plugs and contacts changed/cleaned
Code also showed lean on bank 1 for the pre-catalytic converter O2 sensor

Please, any help is appreciated

 

[jascolt]

Hello? Bueller? EchoEchoEcho

 

[Cracker]

Hmmm... you might get more, and quicker answers by checking www.yotatech.com ...They're 90% 4Runners on that site...

 

[SteveH]

Lean bank errors often indicate a leaky intake manifold - at least they do on GM junk.