And we reach the end of the list with one most people donΆt know, or really even want to hear. The fact of the matter is that early water-cooled Porsche Flat-six motors are pretty much junk, an expensive game of automotive Russian Roulette that most owners donΆt even know theyΆre playing. Problems are multiple, serious, and ugly. TTACΆs Jack Baruth has spoken at length about how terrible the early waterboxers are, and even I found a lot of it to be a bit scary.
The 996 generation 911 was the first big change for the 911 since… well, since 1964. The Flat-six engine gained water passages and a radiator, much to the horror of the Porsche purists. But the level of cheapness built into these engines was even worse than the “is this a Porsche?” driving feel. HereΆs a short outline of things that might have gone wrong with your brand new $75,000 911 back in 1999. (Main points taken from a fantastic article by Total 911. Fantastic read.)
» Intermediate shaft failure. This part runs under the block, driven off the crank. ItΆs what turns the cams in both cylinder heads. The sprocket on the end of this shaft is retained by a small stud, which will break and cause the bearing that the sprocket rides on to fail as well. ItΆll start out as a rattling noise and end up with the timing chains coming off, and both heads gathering a few expensive built valves. Fix: rebuilt heads, new sprocket, new bearing, new stud. Or a new engine! $15,000.
» Cracked cylinder heads. Due to a design flaw in how the tappets bolt down, the heads might crack, allowing oil into the water jackets. Which makes oil sludge. Which kills the crank bearings. Which means a new engine! $15,000.
» Cracked cylinder linings. The cylinder linings start as two parts, and the aluminum block is cast around them. The block itself is less rigid than the old air-cooled blocks, and under heavy load it can deform and will develop cracks in the cast-in liners. This leads to coolant in the cylinders, and worst-case scenario, it causes the engine to hydro-lock, bending rods and breaking pistons and deforming the cylinders. The 996 motor doesnΆt have individual, replaceable cylinders like the 993 did, so the whole cylinder bank is ruined. YouΆll need a new engine! $15,000.
» PCV failures will suck oil through the intake, gumming up valves, sludging the oil… you know. This might not require a new engine; breathe a sigh of relief.
» Variocam (VVT) controller failure can lead to poor performance or a rough idle. Thankfully this wonΆt kill your engine!
Now, itΆs estimated that these failures only affect about 5-10% of early 996 (and 986 Boxster) production. Which doesnΆt sound too bad – but if you knew your $75,000 Porsche had a 1 in 10 chance of needing a new engine at huge expense, how interested would you be? WhatΆs worse is that Porsche spent more effort trying to pin the failures on owner neglect or abuse than trying to restore customer goodwill. When the problems are clearly due to design flaws, the best strategy is not to insult your customers and assume theyΆre stupid. There are ways to avoid these problems, mostly aftermarket or updated OEM parts from later cars. A better way? Get a GT3 or a 996 Turbo. For one thing, theyΆre awesome. But they also use the older 911 GT1-derived block thatΆs not a split case, and these motors are almost bulletproof.
So next time youΆre car shopping, keep in mind that just because a car has a reputable badge on the hood doesnΆt mean it wonΆt give you problems of some sort. Do your research first, so you donΆt have to learn of a problem the hard (read: expensive) way. Until next time, friends!
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