Socal Rain? Yes. Misfires after flooded road? YES!

[mnessari]

As the title mentions, we had a good amount of rain here in the Los Angeles area. Had to drive the old lady as shes my daily driver and had to cross an intersection with a good amount of standing water which immediately started causing a misfire, very hesitant acceleration, no check engine or asr light, and the condition corrected itself after letting the vehicle idle for 30 minutes on my driveway. Now moving forward, I have both covers on my ignition coils, splash shield is on, can a compromised lower harness also cause this? Alternator? How to prevent this in the future? How are others dealing with excess rain and still driving the W124?

 

[gsxr]

Misfiring is almost certainly related to secondary ignition system. Are the plastic covers present over both distributor caps? How old are the caps/rotors? Etc.

Lower harness/alternator should never cause a misfire.

 

[mnessari]

Misfiring is almost certainly related to secondary ignition system. Are the plastic covers present over both distributor caps? How old are the caps/rotors? Etc.

Lower harness/alternator should never cause a misfire.

Yes sir! Both caps are less than a year old. Replaced caps, rotors, brackets, and shields all Bosch. I could’ve sworn it may have been the coils behind the headlights. I will pull up an EPC to see if I’m missing anything

 

[gsxr]

Hrmmm. How old are the wires, and if recent, what brand are they?

Unrelated to this rainy-day-misfire problem, you may want to also consider adding vent slots to the new Bosch caps as described here, if you haven't already.

 

[mnessari]

Hrmmm. How old are the wires, and if recent, what brand are they?

Unrelated to this rainy-day-misfire problem, you may want to also consider adding vent slots to the new Bosch caps as described here, if you haven't already.

Sorry for the late response. Wires were done along with the rest of the ignition... Wires are NGK