Running rough/stalling/CEL in rain with weird symptoms

[TheDurtyDeez]

Well drove .5 miles today in hard rain... ran rough, happened before but always started after a few minutes. Only happened one other time. made it home and is back in the garage and trying to find the IDM to see if its wet. Runs good for one second after starting, and drained the fuel bowl. The weird thing is my EGT gauge only registers 200ish and doesnt move with throttle and boost barely moves. All other electronics work and the lights on the gauges work. No smoke just loud and rough running.

Any ideas? TIA!

[Jacob@DP-Tuner]

Just a shot in the dark. But if the windshield is leaking on the driver side, water can run right down onto the PCM and IDM connections, have seen that cause issues with the 7.3L trucks in the past.

[TheDurtyDeez]

i took a light and checked the PCM but I dont have the right socket to get in the wheel well to check the IDM, but thats next on my list! I have had a tiny crack in the filler neck of the gas tank and due to my laziness havent fixed it... if the water seeped in (this is a stretch) and washed dirt down so the clogged screen throw a code and lack of pressure be making my truck run like this? Is the a way to blow back down the line and unclog the screen without draining the tank?

[TheDurtyDeez]

ok, just bought a cheapy scan tool and it says no codes but at the bottom it says missfire... any thoughts what that means?

[TheDurtyDeez]

New evidence... for whatever reason when i smack the center of the driver side wheel well straight up the truck dies as its idleing rough... moisture and a freyed wire on the IDM? Fried IDM? how sould i proceed?!

[NoRalPh]

Originally Posted by TheDurtyDeez

ok, just bought a cheapy scan tool and it says no codes but at the bottom it says missfire... any thoughts what that means?

Go return it, they don't work on our trucks and aren't giving you reliable info. There may be codes even though it says there aren't...

As for the IDM symptoms, you need to get in there and find out what's going on

[TheDurtyDeez]

Is there a way to diagnose the IDM when I get to it?

[timmyboy76]

like the previous post, with a leaky windshield, water will travel down, and drop right onto the GEM module, located behind the fuse box. Also, look atthe 42pin connector, located on d/s valve cover, check for frey wires tthere.

[TheDurtyDeez]

Well I found A problem if not THE problem... it seems its a fuseable link? Directly off of the driverside batt going to the fuse box, now its broken completely. The cable from the batt, and the 2 12ga wires which is the broken side seem to be shot! Is there an easy way to fix this RIGHT?

[NoRalPh]

Ya mean this one -> POTENTIAL ELECTRICAL CORROSION if your truck is like mine......