Fair warning: this will be a long post but wanna make sure the full picture is shown. Will also attach pics from OBD II.

Originally truck overheated bc a line was blocking the fan from cooling when truck wasn't in motion. Still had to drive home, stopping everytime it almost redlined to cool down and add water when possible. Since then i have listened to too many people that SHOULD know what they're doing, they did not, and has cost me over a grand in parts that I have put on myself to include a "highly recommended mechanic" pinpointing a faulty PCM (included in cost of parts above). Since I have done A LOT of my own research diving into a deep study of OBD II scans. That said, the startup from cold is rough, whether cold or warmed up will not stay running without constant pressure applied to the gas pedal. New PCM is throwing DTC codes P0442, P0500, P1281, & P0138. When trying to get the RPMs to hover around 1000-1300 I can hear the knocking that goes away once RPMs get higher. Sometimes there's a popping out of the exhaust when in Open Loop Mode. I found the small EVAP leak...rotting elbow joint right at the top of my LDP. Haven't done much in reference to the fuel injectors due to needing another set of hands. Inspected both Input and output speed sensors on auto transmission: no physical damage to sensors, wiring, or connectors. Also tested out on the multimeter. P1281 is newer code Have replaced IAT, ECT, & MAP sensors recently. Thermostat was replaced a cpl months ago the first time 1281 from old PCM threw and stopped throwing the code. Summarized: nothing I have done has even staggered the symptoms. Guys I really need to get my truck running. Please Help!!

 

Is your truck throttle by wire? Or is there an actual throttle cable from the pedal, to the throttle body?

 

Throttle by cable from the pedal. Also, side question: so under the battery tray (not the purge selenoid) there is a silver "something" with what appears to be a vacuum line running to it. Can't telk where the line runs once it goes under the tray. What is this?!?

 

Cruise servo?

Have you cleaned your throttle body lately?

 

Cruise servo? Would you mind explaining that to me please? And I did clean my throttle body roughly 2 months ago with very little run time since minus the 10-15 mins every other day I had been cranking it and trying to get the new pcm familiar with the system.

 

Never mind the explanation of the cruise servo.... I did find out that that is exactly what it is so thank you for that

 

Still have a mopar IAC in there? Or is it aftermarket? (I had zero success with aftermarket IACs in my truck.....)

 

You make a very good point. I've already had to swap out my O2 sensos from Bosch to NGK. I'll go thru all my receipts and check. If you don't mind, when I do ill post which ones I've changed and their brands. If any seem questionable I'd really appreciate letting me know

 

We can do that.

 

This is a list of all the parts/ sensors I have replaced that are not the same manufacturer as the original factory parts.

Air Intake Temperature Sensor: Mopar
Thermostat & Housing: Motorad ( 195°)
Vehicle Speed Sensor: Delphi
Idle Air Control Valve: Carquest Premium
Engine Coolant Temperature Sensor: Duralast
PCV Valve: Dorman

When I was making this list i did discover that the original thermostat was 180° instead of 195°. Would that possibly be the cause of the P1281 DTC?