Water leakage onto rear ignition coils - how much of an issue is it?

[cyanutopia]

Hi NSXPrime community, I am a soon-to-be NSX owner and was reading some information about water leaking through the vents on the hatch onto the rear ignition coil packs causing rust and damage to coils/plugs resulting in sluggish acceleration and misfires. A few questions:

1. How prevalent is this problem --- do all NSXs have this issue?
2. Is there a way to prevent water from getting into this area?
3. plan to use my NSX as a daily driver, rain or shine, so will this become an issue if I drive it in rain? There is no snow where I live.
4. Also, what is the best way to prevent water from getting into the engine with car washes and does this mean that I cannot take the NSX to a carwash that uses a machine to wash it?
5. Are there any aftermarket parts that prevent this issue?

Thanks in advance for your responses - the NSX prime community is terrific and I look forward to joining you as a fellow owner :joyous:

 

[TyraNSX]

It's not that common if the covers are on the correct bank & the gasket on the upper edge is in place. And you don't blast water directly on the engine.
And search is there for a reason.

http://www.nsxprime.com/forum/showt...-water-in-spark-plug?highlight=water+in+coils
http://www.nsxprime.com/forum/showthread.php/121080-water-in-rear-coils!!?highlight=water+in+coils
http://www.nsxprime.com/forum/showt...to-electrical-system?highlight=water+in+coils
http://www.nsxprime.com/forum/showt...r-after-rain-or-wash?highlight=water+in+coils

Plenty more if you search

 

[cyanutopia]

Thanks for the response - have you guys had any problems with taking your NSX to commercial car wash places and water getting in places it is not supposed to?

Also congrats on your Zanardi

 

[DocL]

When I replaced my coilpacks they were extremely rusted and I know it was caused by commercial car washes. Whenever I used to take my car through them immediately afterwards my car ran like $hit.

 

[jond]

The rubber seals do go bad on coilpacks and water will get in them. It feels like your car is BROKE when it happens.
It's not a big deal at all though. Your Acura dealer will have you back on the road in a few hours(after they get the part).
I've only had 1 coil pack go back and my car is out in the rain all the time.
I can't remember how expensive it is. I want to say $700ish?

 

[Honcho]

When I replaced my coilpacks they were extremely rusted and I know it was caused by commercial car washes. Whenever I used to take my car through them immediately afterwards my car ran like $hit.

Laserwash!

Seriously though, it is an issue. Best bet is to make sure the rubber coil cover gasket is in place. NSX in motion in a downpour is not a problem. But I have noticed water pooling down there after a car wash.

 

[Sportsmind4me]

Why would you EVER take your NSX to a car wash and NOT wash yourself? It's better for the paint and it gives you more bonding time with the car.:smile:

 

[kennyc]

big issue with mine... Replaced 6 so far.

Now I cover the vent (garnish) before I hand wash.

 

[HondaDreamS]

Ive been fighting this battle for a while. the rear vent allows the water running of the engine hatch to cascade through it falling right on the rear coils. My plan is to use a rubber barrier/guide to channel the water to the passenger side shock tower. There is a nice landing that a guide can be attached using a proper water resistant adhesive. . Also if you take a close look at the rear vent the screw holes that hold the vent secure to the body also allow water to pour down them on to the rear bank. So a solution is to channel all the water away from the rear bank and plug the rear cowl/vent mounting hole channels. Hope this helps

 

[whs520]

Ive been fighting this battle for a while. the rear vent allows the water running of the engine hatch to cascade through it falling right on the rear coils. My plan is to use a rubber barrier/guide to channel the water to the passenger side shock tower. There is a nice landing that a guide can be attached using a proper water resistant adhesive. . Also if you take a close look at the rear vent the screw holes that hold the vent secure to the body also allow water to pour down them on to the rear bank. So a solution is to channel all the water away from the rear bank and plug the rear cowl/vent mounting hole channels. Hope this helps

Hi, all,

Replying to an old thread, but I just ordered the below:

Coil Guard – Davis Design Fab

davisdesignfab.com

Hopefully this coil guard works well (there's a video on Youtube of the install):

 

[MotorMouth93]

Good luck. I found that kit to be largely pointless and mostly just a feel good measure. The part that actually matters is the adhesive weather stripping, and the adhesive doesn't hold up for long under engine bay conditions.

Replacing the coils with modern weatherproof coils is the real fix, such as K series or Audi coils.

 

[Old Guy]

Changing the coils does require that you can modify the dwell times times which not everybody has the skill to do. Coil bodies that are 100 % encapsulated will eliminate that nasty coil delamination that occurs on the NSX coils; but, won't fix the problem of water getting down into the spark plug well and then up past the coil nose boot (how does it do that?) causing tracking on the plug insulator.

As @Honcho notes, well fitting gaskets on the coils covers is the first simple line of defence. It also helps if the coil covers are not reversed - when I did the plug changeout on my car in 2019 I discovered that the previous service tech had switched the FF for RR. You can switch them and they will screw in; but, they don't seal. New gaskets slathered with silicone grease will help those correctly placed coil covers to seal.

I wash my NSX regularly using a pressure washer for initial dirt removal and final rinse. I try to avoid hitting the rear vent with the pressure washer; but, water still goes down there. When I did the plugs in 2019 there was no signs of corrosion on the coils despite the reversed coil covers, probably because I have never seen signs that water is dropping down onto the rear head from the outside. I have a 2000. I haven't checked the part numbers to see if there was a revision; but, I am wondering if Honda made a design change to the rear garnish during the production run because moisture ingress has been a non issue for me (so far).

 

[Honcho]

100% agree with Old Guy. A good silicone grease on the sealing rubber is the best thing you can do to protect your spark plugs. Mine always come out shiny. It's a super cheap and easy way to avoid misfires due to corrosion of the spark plug terminal.

So, far, I've been lucky with the Davis Design coil guard kit. The adhesive is still sticky and the coils have stayed dry despite many washes and a torrential downpour on my aborted drive to the car show over the summer. If installed properly, it does a good job of diverting the water flow away from the rear head. Time will tell though.

That said, I'm probably going to change to the K-series coils at some point, since I can change my dwell times via the Demon.