TJ with P0171 & P0174 codes

[dan-cj7]

Hi guys,
I’ve had these codes pretty much since I’ve bought the Jeep (2005 model) a year ago and thought it was time to start looking into it.
The first thing I did was put some premium fuel in to see if it was a minor error or something worth looking into. The light went away for 3/4 of that tank of fuel and came back.
Since I was getting both codes I thought it will probably not be a faulty o2 sensor. I then got a code for error on the air flow sensor. So thought it might be that. Still getting the lean codes.
The next thing I was going to check was a vacuum leak. I couldn’t hear or see anything.
I bought a obd2 scanner because I found a video that showed if fuel trim was ok, then you didn’t have a leak. Just tested it and short term is close to zero and long term is around 10. Which seems to be normal, right?

I’m thinking now it might be the fuel pump or filter which on the 2005 model involves dropping the fuel tank.

Before I do that I was thinking I’d ask here if anyone would have any other ideas.

If you do please let me know.

Cheers
Dan.

[Fishframe]

My 2005 TJ fuel pump failed 12 months ago after these codes came up. Could well be a fuel pump. Start shopping now for a decent one - Bosch. The other aftermarket ones are crap, I know because that is what I first used. I managed to find Bosch on Amazon but they’re getting rare. By the way, when the fuel pump failed there was no warning, I was lucky enough to be able to roll off the road with no power what so ever. Also, when the fuel pump is installed it has to be inserted very carefully because the wire ‘rod’ which operates the fuel sender gauge is quite delicate and if damaged your fuel gauge will be even less accurate than it is now.

[destron]

Check the exhaust manifold if there's a crack.