ford econoline 2001 e150 v6 4.2l
ive been fighting lean codes for 3 years now. every now and then i fix something and it gets better but then it comes back. at this point all my hoses are new all new seals very many new parts including fuel injectors, gas and air filters pvc valve egr valve purge solenoid, maf sensor, vacuum solenoid. i rerouted the ac line and put a new air housing in bypassing the one over the wheel well(cause the ac didn't work while accelerating). still believe i have an air leak somewhere but i cant find it. i dropped egaust system and cleaned out caty and changed a lazy o2 sensor (had alot more power for a few days) lean codes came back. it read lean on bank two. but so now i had a misfire on cylinder 5. moves fuel injectors between 5 and 4 and the misfire went with it. bingo bad injector. put brand new injector in but misfire came back in 30 miles or so but with no lean codes. so now i have a misfire on cylinder 4 with brand new fuel injector. AND YES ALL NEW PLUGS WIRES AND COIL PACK.....duh

side note for more info. ran a compression test from cylinder one it reads in order 170 160 160 160 160 155

fuel trim read all good except long term fuel trim bank two which sits around 25 at idol and corrects under acceleration (vacuum leak that i cant find)

im caving and getting smoke test asap but my question is.....could this be a pcm problem and if so does anyone test them before i buy a new one. most places wont take it back and im all tapped out from rebuilding this already.

 

You might consider trying this, Remove PCV valve and plug it.
shoot some brake cleaner, (one small shot) into the oil fill hole on the valve cover. If RPM picks up , good possibility of leaking intake manifold gasket(s).

 

that does nothing. like i said all seals arr new.
update: if i reset pcm the van runs great untill i turn it off and back on. today tho the pcm was reset and after 20 miles or so the light came back on but my obd scanner isnt picking up any codes. tried a stores scanner still no codes. i am failing evap test and the caty light was flashing.

 

In spite of our best intentions , things go wrong.
I understand you replaced the intake gaskets, but the test I suggested just verified there is no problem there.
Now you have to look elsewhere.

Just because all the parts you listed are"new" does not mean you could not have installed a defective "new" part, very common these days.
You need to know and understand how to determine a part is malfuntioning.
It could be a part, a poor connection and possibly something you think is not related and yet is causing a problem because you don't know how to check them out.
You replaced all the vacuum hoses ,you say, but did you check the components the hoses supply vacuum to? f not, you might want to start there.

 

yes. almost all parts in that line are new. ive ran tests on everything i can think would cause the problems. all plugs have been tested for voltage. ran smoke test and no signs of leaks. the injectors have been listened to for clicks. all spark wires firing. vacuum lines have been pinched to make sure for changes. seals have been sprayed around to look for changes. pulled spark plugs to check for any odd or bad wear they all look good. o2 sensors all reading voltage. listened for caty noise after cleaning, nothing. i have a stethoscope i listen to these parts with. just changed the misfiring fuel injector back to 5 to see if the misfire moves. need to test drive it and then ill go from there again
of it was a bad seal or vacuum line why did the misfire move with the injector....in your opinion

 

Since I cannot be there to check and see certain for myself,is the vacuum tap anywhere near the injector intake runner?