The original Porsche Boxster is an astonishing amount of car for the money, but it comes with some pitfalls. Everyone knows about the infamous IMS bearing issues, and a few people have found that timing chain guides can get brittle after a few decades, but there’s a less-discussed hidden Achilles heel on the 986 Boxster that can actually brick the car. However, for things to get that bad, a little bit of cleaning needs to be neglected. Let me explain.
The original Boxster is something of a packaging miracle. Porsche had to fit a rear-mid-mounted flat-six engine, two trunks, a functional stainless steel roll bar tied into the chassis at four points, a space-saver spare tire, four four-piston calipers, six speakers, two radiators, four airbags, an entire power convertible top mechanism, space for two passengers, and room for 255-section rear tires into a package roughly the size of today’s BMW Z4 (Oh, except for the 95.2-inch wheelbase, which is shorter than that on a Z4). We’re talking about a tiny-by-modern-standards mid-engined roadster that can swallow two carry-ons, a couple of duffel bags, and just enough camera gear to channel your inner Ansel Adams, all without looking like a poorly-proportioned kit car. Mind-blowing stuff, right?
Due to fitting so much stuff in a relatively small car, there wasn’t much room left for the immobilizer module, the electronic security computer that does a secret handshake with the engine ECU to mitigate theft by disabling the ignition should an incorrect key be used. In short, it’s the module many Hyundai and Kia owners wish they had, but just like any older computer, the immobilizer module on a Boxster wasn’t exactly small. However, the area under the driver’s seat is free real estate, so Porsche stuffed it there. I gotta admit, that’s a pragmatic move. BMW fills the same area with audio woofers, and numerous other cars have everything from amplifiers to tire changing equipment cached under a seat, so there’s definitely precedent for locating electronic components at the lowest point of a car’s cabin.
Speaking of packaging, every car needs drain holes in recessed externally-accessed compartments, and the Boxster is no exception. Since the convertible roof, once folded, sits in a compartment beneath a hard tonneau cover, that tonneau cover has exposed edges just like a hood or a trunk lid would. Also like many hoods, the hard tonneau has some level of sealing, but it isn’t perfect and rainwater can run down into the convertible top storage compartment beneath the tonneau even with the roof up.
To manage water ingress, the top storage compartment, pictured above, features a foam trough with drain holes connected to piping that leads down to just ahead of the rear wheel arches. However, Porsche forgot one crucial thing — it didn’t put any mesh on the holes in the trough. As a result, any leaves, dirt, and other debris that slips past the tonneau seals can cover or otherwise clog the drain holes. If you know anything about gravity, you probably know where this is going.
Once those drain holes clog up due to insufficient maintenance, water backs up and runs into the passenger compartment, eventually settling on the floor. Uh-oh, isn’t the sensitive electronic immobilizer module also on the floor? Why, yes it is! Given that most people don’t consider cleaning their cars’ drain holes to be part of regular maintenance, the consequences of leaving out a few grams of mesh are predictably both common and expensive.
How expensive? Well, the last 986 immobilizer replacement I quoted for a customer in a past life had a total retail cost cost north of $2,000 and required programming using a Porsche PIWIS diagnostics and coding system. That’s not exactly equipment everyone has laying around, so lead time on immobilizer module replacement may leave an affected 986 out of operation for weeks.
Oh, and when I say out of operation, I really mean it. There’s a solid chance that a 986 Boxster with a damaged immobilizer module just won’t start. Other symptoms may include windows and a horn with minds of their own, non-functional key fobs, electronic trunk latches on later models that just don’t work, and an inoperable cabriolet top, since all of those functions are tied into the immobilizer module. Christine? Is that you?
Porsche, eventually sensing it had made a significant mistake, rectified the lack of drain mesh on the subsequent 987 model from 2009 onwards. In fact, Porsche part number 98756148700 “Water strainer” doesn’t just fit earlier 987 models, it fits the 986 too. Considering that each mesh wedge costs around $10 and only two are needed per car, that’s dirt-cheap insurance against a waterlogged immobilizer module.
Also cheap insurance? Going through the drains periodically using one of those long, flexible trombone cleaner. This one time at band camp, am I right? But for real, these things are cheap and awesome at cleaning drain holes, probably because they’re meant for cleaning spit out of that instrument every teenager used to make racecar noises. On a more expensive note, there are companies offering waterproof immobilizer cases that you seal with silicone, which don’t just guard against clogged drains but also prevent heartbreak due to getting caught top-down in heavy rain.
However, don’t let water drainage issues dissuade you — most common 986 Boxster issues can be worked into regular maintenance. That IMS bearing? Do it with the clutch since you’ll be dropping the gearbox anyway. The drain holes? Buy the covers, and work cleaning out leaves and whatnot into a quarterly routine since it’s damn near free. With a little time and effort, you can enjoy one of the last great sports car bargains, a playful mid-engined roadster with outstanding parts support. It writhes and screams and vibrates your fingertips like a sports car should, and when you’re done living north of 4,000 RPM, it settles down and becomes demure, composed, and reassuringly cosseting. The truth is, greatness requires effort. Don’t let the fear of failure stop you from trying.
(Photo credits: Thomas Hundal, eBay)
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