Joe,
You should check and see what part of the coil is leaking. If you keep getting pin holes in the outer radius bends, you should write Acura a letter. Mine also failed ('91, original owner, about 25k miles at failure about two years ago) so I pulled it myself to see why. When I found that the coil was in no way worn from contact (rubbing) and that the protective coating was still in as new condition, and that the pin holes were ONLY in the outer radius bends (where the aluminum is stretched to turn 180 degrees), I decided it was time to write Acura.
I've heard some say electrolysis causes the aluminum to weaken, but I'm inclined to believe several temperature cycles continue to expand and contract the coil until it fails at its weakest point (the outer radius bends). My degree is in engineering, so it may be fair to say I understand thermodynamics and assembly processes. I told Acura that I was reluctant to install another e-coil when it appeared to me that without a design change, I was going to see another failure. They comped me another e-coil, but I had to do all of the labor (about ten hours the first time). As strict as the EPA is, it might be in everyone's best interest to have them apply some pressure on Acura so that they can then apply some pressure on Showa, the e-coil manufacturer. When (if) mine fails again, you can be sure I'll go that route.
I wonder if most of the failures can be localized to warmer climates. Ken's '91 has never had a problem, but he lives in Chicago. Safe to say his AC has not been cycled nearly as many times as mine down here in Texas.
If you write Acura a letter, be nice. The problem is with Showa. BTW, other Showa e-coils on other Acura models are also failing.
FYI, Showa also makes the front forks for Honda motorcycles as well as the rear shocks. When I raced dirt bikes, the big dilemma was, get the Honda for the motor and send the Showa shocks off to be rebuilt or buy the Kawasaki for the suspension (Kayaba) and send the motor off to be rebuilt. If you follow 600 cc supersport motorcycle racing you will know that the factory Honda riders, running the Works Showa suspension, were being outdone by the privateer Honda teams running the Ohlin suspension. It appears Showa needs to hire a couple really good engineers. Did I say that?