92 F150 I-6 300, auto, 4x4, 144k miles
Quick History:
About a year ago it started getting running rough. Mostly at part throttle while driving at highway speed. It has progressively got worse to the point it won't even start if it is below freezing. Above freezing it starts, but runs rough. It is getting progressively worse. I have checked fuel pressure, replaced fuel filter, replaced TPS, replaced O2 sensor, checked timing, replaced wires, cap/rotor and plugs, use seafoam regularly. Runs good at high RPM, just not full power.

CODES:KOEO
327....EVP/EPT valve position circuitbelow min. voltage
328... EGR closed valve voltage lower than expected
332....Insufficient EGR flow detected
452....VSS Signal Fault

CODES:KOER
213....SPOUT Circuit open... but it has never been removed. In fact it was still taped to the wiringing harness as it left the factory.
172....HEGO (H02S) sensor fault/lean... Replaced 02 sensor last year when I 1st started getting this code
225....Knock Sensor fault during dynamic response test (probably my fault)

Thanks in advance

 

Lean code could be from fuel pressure. This engine runs around 60 psi, not 45. Also, the 4.9 is very bad for dirtying up fuel injectors. Just fixed one a while back for about the same thing by flushing the fuel injectors about 4 times with a system that bypasses the fuel lines and runs off concentrated cleaner and gas mix in a pressurized bottle.

 

Fuel pressure was about 45PSI, but it was that way on both tanks. Isn't there 2 pumps, one in each tank on the 1992? Any chance both fuel pumps are failing? Didn't seem likely to me.

What were you using to clean the injectors? I remember back in the late 80's using a bypass type cleaning like you mentioned, but haven't seen that in many years. Smoked like a train if I remember correctly.

Would replacing my injectors be the next step, or should I try a different cleaning method.