SO finally got the the motor in and everything figured out. Was running FLAWLESS for about 70 miles or so. Today after fixing a small fuel leak, fired it up and was around 2500 RPM when it started running rough and smoking black, even at idle. Checked codes, came up with

P0264 Cylinder 2 Injector Circuit Low

P1271 Cylinder #1 High To Low Side Open

P1272 Cylinder #2 High to Low Side Open

Did a buzz test and all were fine, so they're getting signals. While running, i unplugged the driver side rear harness and there is almost no change (still runs rough) Im assuming this is the plug for cylinders 1/2. Plug and harness looked fine, not burnt, but haven't checked under the valve cover. Is the next step pulling the VC off and seeing what it looks like under there? Its weird that it ran fine then all of a sudden started this. Brand new VC gaskets with only 70 miles on them. Any guidance appreciated guys.

 

Or idm.sorry rob.glad you are getting there at least.

 

If it isn't one thing its another lol. But thank you. Is it possible the IDM would just cause problems for those 2 cylinders?

 

Yea.a possibility.get Aaron to let you try his.easy test.

 

Gotcha. Ill try that first. Everything else I've read says to test the injector wiring with an ohm meter. Im assuming to do that just disconnect the harness and do it between the pins right?

 

#1 and #2 cylinders are on opposite sides of the engine. Usually the IDM will shut down one whole side if there is a problem. I would check all the wiring to the pigtails real good and make sure none of the connections have come loose.

 

Ill do that bill, going to test the resistance as well. Stupid question, but what exactly are they referring to when they say the high side and the low side of the injector?

 

The "high side" is the common power to all injectors on that bank. The 'low side" is the ground signal to each injector.

 

Good diagram, saved. So I will never understand why the truck gremlins decide to **** in my cheerios, but i swapped the IDM with aarons and the problem is gone. Cleared the codes, none came back. Crazy how it was working fine one second, then the next went bad. Appreciate the tips. For anyone else finding this with the same issue, Here is another link i found. hopefully this will serve as help. https://www.ford-trucks.com/forums/8...-inj-code.html

 

Well.at least you know without tearing into wiring headaches.
How's it running with them new sticks?

 

Huh. Learn something everyday.

I always thought the center wire was the ground and the injector specific wires were the 'hot' ones.

 

Sorry, i somehow just saw these posts. They were running fine lol. I still haven't been able to see what they can do as i haven't made it through my breaking period on my clutch. 425 more miles.....