HELP! list of issues inside.

my 99 Tacoma which has been my daily driver since I started college in 2007 has been acting up lately.
CEL reads P0171(If I remember correctly): too lean on bank 1
Randomly, the throttle will cut out for a 1/2 second or less while at partial throttle.
Occasionally when this happens I've tried to accelerate and even with it on the floor it feels like it's bogging down.
Lastly: I feel like I'm idling too low. 6-700 RPM at a stop. Its to the point that the truck will cut off at times, but not often.

About the truck: 275k miles. Stock, no offroading. 95% of my miles are on the interstate. New plugs and wires 10k or so miles ago. Also I've had to change a single injector once before probably 30k miles ago.

I've replaced the TPS sensor, MAP sensor. Up next are checking the vacuum lines for cracks or leaks.

What else can I do or can someone help me narrow down this issue?

 

Have you pulled the spark plugs to check for compression and to see if you are running to lean on bank 1? Checking the vacuum lines and intake side for leaks would be a good next step. Try the wd40 test around that bank and see if you can find the leak. It could be a sensor issue, maybe the o2 sensor has gone bad on that side?

1. Pull a plug and see if its lean or rich
2. Test for leaks in intake and vacuum lines
3. O2 sensor if the plugs look rich

 

How many miles does your fuel filter have on it? Might want to replace it if it has over 40,000...

 

Check fuel pressure also.....You may have a failing fuel pump.

 

I'm going to get on it tomorrow once I can get into my garage. i'll run through everything listed and get back to you guys. Thanks for the quick responses.