So I've owned this truck for about half a year now, its a 1996 F150 4.9L V6 RWD Automatic Regular Cab Long Bed.

Now to my problem. My check engine light is on, I went to O'Reilly borrowed their code reader and it reads System Too Lean on Bank 1 and 2.

So I reset the codes, waited another 150 miles to see what came back.

Well sure enough, System Too Lean on Banks 1 and 2. Now my truck has no problem turning over, even with the mornings in the teens. Its after it starts to choaks up and I basically have to put the pedal to the floor to keep it from dying. RPMs will jump, let off the gas, runs fine after that.

Now it's only occasionally that it gets choaked out. Would the logical conclusion then be that its somewhere along the fuel lines, a bad fuel filter, or fuel pump?

I should also mention I have dual tanks and it I can't remember if it's ever happened on the dual but 99% of the time on my front tank.

EDIT: I also realize it could be a bad O2 sensors or the mass flow but this occasional trouble starting leaves me to believe its somewhere along the fuels travel from tank to engine.

 

Have you actually opened the hood and looked at your engine? It's NOT a V6. The 4.9 is an inline 6. Please do not insult it.

Starting and driveaway issues could also be the IAC.
Have you changed our fuel filter? If not, do it.
Are the HEGO sensors original? If they are and there's more than 60K on the truck, they may need changed (you have 3 of them)

 

I know it was an i6. Some dude ripped me a new one for saying i6 on another forum so I thought I'd just leave it as a v6. Good to know it's actually called an i6 and that guy is an idiot.

Anyways, I'll replace the fuel filter after work today, clear the codes and see if they come back.

I believe they're the original sensors, the truck has 150k on it. I'll look into replacing these as well.

One again, sorry for calling it a v6. I knew it was an i6.

 

Check for vacuum leaks.

 

Actually, after looking at my engine I noticed my vacuum line had been snapped this entire time. I thought the shop I took it too would've noticed this but as soon as they saw System Too Lean (Bank 1 & 2) they quoted me $200 to replace the three sensors.

Well $4 later, the line is fixed. I drove around for 10 minutes to see if it would trip again but it hasn't yet. So I guess we shall see over the next week.

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Any shop who wants to replace the O2 sensors for lean codes is either incompetent and/or ripoff artists. The sensors are doing their job fine, TELLING you it's too lean due to (usually) unmetered (by the MAF) air entering the intake.

 

Well when I first got the truck I took it in to get it inspected. Failed inspection because of ball joints and exhaust mounts.

So I paid this other little shop called Muffler Doctor to weld the muffler up for me and they noticed one of the O2 sensors wasn't even plugged in. So they plugged it in welded it up.

I replaced the ball joints. I've decided to avoid shops at all costs with this truck.

Most the work I can do myself and anything I can't my retired Grandpa (use to be mechanic) or my uncle who has rebuilt a couple old beat up cars in his free time would be glad to help me.

My next course of action is to replace most if not all the hosing I can in the engine, then replace my steering column which is about to snap according to the shop that did the initial inspection. It makes a god awful whining sound when I turn but it also is only started doing it when it got cold out.

 

Steering column about to snap? I think I'd get a second opinion on that. Whining when turning when cold is most likely the power steering pump getting tired. Suck the fluid out of the reservoir with a turkey baster and replace with synthetic ATF.

 

Replace the power steering fluid with synthetic automatic transmission fluid?

http://www.youtube.com/embed/q5vFmv7wCHo Here is a clip of me parked turning the wheel left, right, the back to the middle with the door opened.

My wheel sits ****ed. I know I need a realignment. Waiting till I get knew tires.