n14 misfire under load and at hot idle

Yes I swapped them around and same thing at number 4

 

Any fault codes? Did you check the valve lash?

 

Yes
Was getting a 321 code am about to change harness now but harness look good? Still trying to figure this problem out my next step is ecm if harness doesn’t work. Any more advice is well appreciated Thankyou in advance

 

Connector pass-throughs in the rocker box housings. ECM is always dead last.

 

Oh yes I Changed those
Was getting a 343 code also and the count is at 255 which I believe is max

 

Changed harness same result thinking ecm ? @Heavyd

 

Well, sadly you are running out of things to replace LOL. I would try a test ecm first. Call around for any shops to see if they have any. I'd hate to point to that only to find it isn't the problem.

 

Yep that would really be a bummer
But cause of where am located a test ecm is unavailable and the only way I can do that is if I buy one from the states and ship it to my country.
Will keep you posted

 

Welp jus changed engine position sensor and motor is running worse really bad idle. Bought another one to make sure it wasn’t just a faulty one but same result

 

Check all the ground connections for rust, maybe fuel pressure or air in the fuel, maybe harness- check with NOID light if there is enough continuity between injectors and ECM, saw injectors good at idle but when go over some rpm they start to miss, make sure ecm gets enough power from batteries, maybe the steering wheel switch is bad but dont think so, check if fuel shut off valve/solenoid getting enough power, maybe clogged cooling plate behind ECM or valve on that plate blocked by debris, maybe clogged small fuel filter on the fuel pump, new engine harness, in my case turned out to be ECM when getting hot started to miss at idle, nothing under load or cold. I would get new ECM or take old one to some electronics repair place and tell them to check electronic parts for being loose, burned or simply broken circuits in between this components. After so many years on the road this ECMs get destroyed because of all this bumps and holes in the road. Till this day no problems since and getting over 7 mpg. Good luck!