E36 325i prevent water getting into dme

[Jethro91775]

Hi guys

I recently replaced the dme in my 325i. Woke up to some rain this morning. Now stressed that water is going to get into my dme again. Any way I can water proof the dme.

 

[danieljames]

Ok in new to this side of things. Where exactly does the dme reside?

 

[Jethro91775]

Engine compartment. Passanger side. There is a cover just to the left, behind the fuse box. It's behind that cover. You'll see the harness going into the cover.

 

[danieljames]

Ooooooh. Ok I'll check it out thanks. Maybe try some plastidip over it? It sprays on and then 'rubberises' and can easily be pulled off. A can cost between 150 and 180. Just a thought

 

[Jethro91775]

I was thinking that also. But read somewhere online. It's not advisable to completely cover the ecu. I was also thinking of sealing with silicone or building a fiberglass case for it. Wanted to just confirm with you guys which should I do.

 

[danieljames]

Hi Jethro. I assume this is what you are speaking about (see pic). From what I can see it's very hard for water to get in there unless your rubbers aren't sealing properly. Also as u can see mine has a foam covering over it (although somewhat damaged). Maybe u have a leak from under the cover that sits below the windscreen or a blocked gutter. I'm speculating and haven't removed anything to investigate further.....unless I'm looking in the wrong place lol

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Don't know if that pic is showing.

 

[Jethro91775]

Yeah right place. But from what u have read online. There is a problem with the drainage behind that cover. And floods the dme. So tomorrow I'm drilling the drain holes bigger and make a fiberglass box with breather holes in it.... or just re locate dme. Harness seems long enough.

 

[danieljames]

Sounds like a plan. Will Def consider this if I ever have issues. Btw-----how did you know to look at the dme....as in what were your symptoms?

 

[Jethro91775]

Cylinder no 3 was not firing. So we did compression test as well as swap coils. Found no compression on no 3. Did a rebuild. Still no spark. I'm an electrician and do a bit of electronics. So decided to check the Lead to the coil. Found there was no impulse telling coil when to fire. There was a negative voltage across the impulse lead. Back traced cables to look for ground short. Ended up at dme which looked like it was sitting in water for a while. And so goes my 11k story.

 

[Bavs108]

Isn't the DME in a water tight box?

 

[Jethro91775]

So I thought also... apparently not. Water still gets in.

 

[danieljames]

Cylinder no 3 was not firing. So we did compression test as well as swap coils. Found no compression on no 3. Did a rebuild. Still no spark. I'm an electrician and do a bit of electronics. So decided to check the Lead to the coil. Found there was no impulse telling coil when to fire. There was a negative voltage across the impulse lead. Back traced cables to look for ground short. Ended up at dme which looked like it was sitting in water for a while. And so goes my 11k story.

$#!t bru. That's a bit hectic.....hopefully I'll never have to go that far

 

[Jethro91775]

Yeah... I would like to throw the guy who owned the car before me over a cliff. Never bothered to take care of the car.

 

[danieljames]

You win some you loose some. Goodluck chap