Water in ECM?

[skneeland]

Is it possible to get water in the ECM? i washed the engine bay yesterday and now have this list of DTC.

It will run....poorly and im still able to flash the ECM, i just cant clear these codes.
I pulled apart every connection i could find under the hood, cleaned it with contact cleaner and hit with the blow-dryer before re-assembly. I also threw a charge on the battery, rechecked the grounds and ran a temporary ground straight to the battery with no avail.

any thoughts? it looks like its one bundle of sensors that isnt getting full voltage

[GMPX]

Those ECM's are sealed up really well, I doubt water got in, but I agree it's like you are missing a 5V reference to a bunch of sensors.

[2007 5.9]

Maybe not in the ECM ,but possibly in the harness and shorted a circuit out?

[easymon]

Check the ecm harness plugs have seen moisture get in there had that happen to me when pushing thru snow banks andgot the engine conpartment full of snow and ice.

[skneeland]

ive had the ECM plugs off 3 times now & cleaned and dried each time.

i pulled out the multimeter and checked the MAP sensor plug as it was one on the list. there was a steady 4.95v on the power wire.
on the ground however, the resistance would hold at 4.0 ohm then spike up to over 12.0 ohm for a few seconds before returning back down to 4 for some reason. im tempted to jumper in a ground lead direct to that wire and see what happens.

[skneeland]

this morning i cleared DTC and it started and ran fine. no more codes but it has a "miss" now and then. There must be a connection im missing, or perhaps a bad wire that didnt like the water.

this was a good read tho:
http://articles.mopar1973man.com/3rd-generation-dodge-cummins/60-obdii-error-codes/361-p0652-low-voltage-at-the-1-sensor-supply-circuit

[killerbee]

Open the hood and let the sun beat on it for a day. I agree it is not likely that water got into the ECM.

Out of curiosity, did you pressure wash it?

[skneeland]

Open the hood and let the sun beat on it for a day. I agree it is not likely that water got into the ECM.

Out of curiosity, did you pressure wash it?

i soaked it at the carwash with their "tire & engine" cleaner for about 15min, then stood back and rinsed it keeping the direct spray to a minimum

[joecar]

...
i washed the engine bay
...Bad deal, avoid doing this.

[anarchydiesel]

More than likely water got into the TIPM.

[skneeland]

so i got back home after letting it sit most of the day and when i tried to fire it up all the above codes popped up and it ran rough.

after rechecking connections i replaced the rail pressure sensor and now it runs like nothing happened, go figure........