Extreme rough rider but only when wet

[Car Addict]

Another year another problem. My 325i has been having issues with the recent snow in the NE. While driving down the road all is well. When you hit a puddle or recently slush mix with the right tire, the engine seems to shut off. Now for the weird part, usually if you try to give it gas the engine will completely die. But if you don't touch the accelerator it will usually stay alive but just barely trying to idle. After a few seconds of trying to die while idling it will angrily let you start to use the accelerator again bucking and backfiring. Finally after a mile or two it seems to be better. But if I hit another puddle or an oncoming car splashes me same thing
Last year I replaced the CPS, fuel pump relay, and main relay.
Two years ago new cap and rotor.

Any idea or how I should go about diagnosing this.

[EyExR]

cracked or damaged ignition wires?

[JCarp90]

Sounds like a CPS.

I replaced mine and the little plastic holder deal broke, it got a hole rubbed in it from one of the belts and that grounded on my upper timing cover. Gave me a very very similar issue.

[Mr. Schwarz]

Spark plug wires? I believe Im having the same problem. Try opening up the harnesses plastic and spray some wd40 (water displacement experiment 40) onto the wires when they are wet and see if it clears it up.

[Car Addict]

Will inspect and report back

[ButtJuice]

I had that exact issue with my 86' eta. I never got it resolved.

[jlevie]

That really does sound like aged ignition wires or distributor.