2007 ford explorer miss firing

[coldroadbear]

Hey guys I 2007 4.6L V8 ford explorer that keeps miss firing. On my scanner its coming up with a random missfire p0300, cylinder 3 missfire p0303, system too lean p0171, and cylinder 4 missfire p0304. Now this is what i have done so far replaced all the plugs got one new coil for 3 due to the fact that at the time only 3 kept coming up. no matter what we did we could put any coil on and it still came up. new plugs for coils and injectors. both cam shaft sensors replaced new map sensor.a new ecm a compression test was done not once but 2 times both times read from 150 to 190 psi. I am lost i need help

 

[09 EX 4x4]

How many miles on your 2007? Does it idle smooth at about 1100 rpm on the tach. Does it run well cold after first start in the morning. System too lean may be a vacuum leak there are ways to check for that. Other than that you have replaced all the usual suspects. I was thinking injector but you changed it. May want to get a 16 oz can of Seafoam and put half in the tank and half in the oil to help clean out the carbon in the combustion chamber and clean the injectors. Could also clean the throttle body with carb cleaner but a dirty throttle body may not cause a misfire. May be a valve getting stuck and not closing the Seafoam may help with that also.

 

[coldroadbear]

it has about 119000 on it i should said its a 4.6L v8 and yes it dose seam to smooth out at anything about a idle