Not long after I got my 2008 H3, I noted that it would throw codes if I pressure washed the front wheel wells or drove through a deep puddle at speed.
I noted some poorly located wiring connectors in each wheel well. They sit on top of the frame just behind the axle. Despite my dealer's objections, I was pretty sure they were the source of my problems.
The first error code was a crankshaft position sensor. This was a big problem, as it changed shift points and made truck drive lousy. Dealer found a way to make that go away, so I stopped worrying about it.
A year or so later, it happened again - this time, just a check engine light without any obvious problems. So, I asked on this and other forums, and learned that the wires to one of the connectors were O2 sensor related.
Finally, while I was fixing some other stuff, and since my warranty was up, I figured I could go for a low-tech fix. I know it's not a good idea to try to seal wiring unless you can do it correctly (condensation will otherwise accumulate inside and make big problems), but I figured I could probably fix a decent splash guard over the connectors.
I used to work for 3M, so I have a bunch of old stuff in the garage. I took some thick mastic pads and put them over the connectors. I left one uncovered sort of as a test. Since I put on the splash guards, I have hit deep water at speed multiple times here during the snow melt, and have had NO problems.
Exposed connector:
Mastic product:
Splash guard in place (adhered back of mastic pad to frame, folded top over connector such that it would block splashes but allow air to move):
I noted some poorly located wiring connectors in each wheel well. They sit on top of the frame just behind the axle. Despite my dealer's objections, I was pretty sure they were the source of my problems.
The first error code was a crankshaft position sensor. This was a big problem, as it changed shift points and made truck drive lousy. Dealer found a way to make that go away, so I stopped worrying about it.
A year or so later, it happened again - this time, just a check engine light without any obvious problems. So, I asked on this and other forums, and learned that the wires to one of the connectors were O2 sensor related.
Finally, while I was fixing some other stuff, and since my warranty was up, I figured I could go for a low-tech fix. I know it's not a good idea to try to seal wiring unless you can do it correctly (condensation will otherwise accumulate inside and make big problems), but I figured I could probably fix a decent splash guard over the connectors.
I used to work for 3M, so I have a bunch of old stuff in the garage. I took some thick mastic pads and put them over the connectors. I left one uncovered sort of as a test. Since I put on the splash guards, I have hit deep water at speed multiple times here during the snow melt, and have had NO problems.
Exposed connector:
Mastic product:
Splash guard in place (adhered back of mastic pad to frame, folded top over connector such that it would block splashes but allow air to move):
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