1996 F-150, 4.9, 5 spd., 2wd. I just bought this truck for $900 but it comes with a few problems so any help would be appreciated.

Codes:
PO411 - Secondary air injection system incorrect flow
PO401 - Egr flow insufficient
PO171 - System too lean bank 1
PO174 - System too lean bank 2
PO385 - Crankshaft position sensor b circuit malfunction

Symtoms:
When cold starting it has a rough idle and will cut off if try to drive it before it warms up a min.
After driving it up to temp. and cut it off it is hard to start. It will turn over twice and stop and then turn over a couple more times till it starts.

Im a pretty good part changer but im not very good at diagnosing. Any input would be helpful as i dont want to just start thowing parts at it.

 

the starting while hot problem sounds like either voltage or a weak/old starter. i would start by cleaning the cables and battery terminals.and by cleaning i mean with a wire brush or sand paper or even a knife in a pinch. clezn till they shine. all cables should still have the insulation on them and the copper wire still be twisted tight and free of any corrosion which could be the white flaky stuff or the green powdery stuff and if they are not all of these replace them. after all that if you still have the slow/no start when hot problem you should have the battery and starter checked. one of these will most likely fix that.

 

Congratulations, sounds like a good deal, that 6 cyl inline is one stout engine.

What have you done so far? Should start with a basic tune up, new plugs, change oil, check spark plug wires for resistance, cap, rotor, air filter, clean IAC, check fuel pressure, check wiring to Crankshaft position sensor (CPS),

 

I agree the basic tune ups are a must. Check with you local Ford Dealer to see if all the recalls have been completed. Ford had many problems with recalls on my truck. Starting problems sometimes are related to worn out wires, cap etc. Check the simple things first.

Is that a 300 motor?

 

I knew i forgot something. Yeah ive already done a basic tune up: oil change, new air filter, clean iac, new fuel filter, new plugs, wires, cap, rotor, and ignition module, replaced obvious cracked and broken vac. lines.

 

I agree the fuel pressure needs to be checked. Also Ford had many recalls on my truck with fuel regulation. Not sure about yours. You might want to check with the dealer about the recalls.

 

What about the codes? Could the egr or evp be the cause of the first 4 codes?

 

Anybody???

 

Just a thought, but I'd take a look at the egr tube that connects the egr to the pass side exhaust manifold. These tubes break and could be drawing air into the exhaust, thus leaning it out. Worth a look, anyway.