2012 Expedition loses power when it rains… what could it be?

Discussion Forum
1

Every time it rains, my 2012 Expedition Limited (5.4L) loses a significant amount of power. After the first drive cycle with poor performance, it throws codes P0365/P0369. I’ve checked both sensors, and they seem fine, but I can’t find any signs of water coming in anywhere.

When I clear the codes with FORScan, the engine goes back to normal with no issues.

Does anyone have ideas for what else I could check?

2

Have you checked if the air filter gets wet when it rains? Maybe water is somehow getting into the air box and restricting airflow.

3

Darby said:
Have you checked if the air filter gets wet when it rains? Maybe water is somehow getting into the air box and restricting airflow.

I hadn’t thought of that, but I’ll check it out. Thanks!

4

@Ari
Any update? Did you find anything?

5

Taliesin said:
@Ari
Any update? Did you find anything?

Nope, air filter was dry, and I couldn’t spot any water in the engine compartment.

6

Ari said:

Taliesin said:
@Ari
Any update? Did you find anything?

Nope, air filter was dry, and I couldn’t spot any water in the engine compartment.

Just looked it up—P0365 and P0369 are Camshaft Position Sensor B Circuit Bank 1 and Camshaft Position Sensor B Circuit Intermittent Bank 1. Could be bad camshaft sensors, damaged wiring, or even a faulty PCM.

7

Could it be water in the fuel system? Or maybe some wet ignition wires?

8

Does it happen right after a cold start in the rain, or does it start after driving in wet conditions? Maybe there’s exposed wiring on the O2 sensors, or even a wet ABS sensor sending bad signals?

9

Finn said:
Does it happen right after a cold start in the rain, or does it start after driving in wet conditions? Maybe there’s exposed wiring on the O2 sensors, or even a wet ABS sensor sending bad signals?

It sits outside, so it gets rained on. The issue shows up when I start driving after it rains—it feels like it’s in limp mode, and pressing the gas barely makes it accelerate. I’ll check the O2 sensor wiring, thanks for the idea!

10

@Ari
Honestly, a lot of us are just staring at the sky and scratching our heads over this one. Hope you figure it out soon!