Had my first DI failure. 1995 900SE (Turbo) 150k miles. Engine has been misfiring -slightly- for a couple of months. I could hear it missing at idle when waiting at a traffic light. A few weeks ago, the -check engine- light came on and stayed on, but the next time I started it up there was no more light, and it hasn?t come on since (not related??). Finally last week - on my way to the garage to get the left CV joint replaced(!!) it started running really roughly. Didn?t know if I would get there, but just made it. While the car was in the garage, the DI cassette went full belly up. Replaced it with new OE part and all is well in the world. Don?t know if they changed or checked the plugs while they had the thing out.
They gave me back the old one, which I thought I would disassemble to have a look, but it turns out the whole thing is sealed in resin, and disassembly is not possible. I can see that one of the projecting contacts is cracked where it makes contact with the plug tip. Also, one component is completely cracked where it sticks out of the resin, but I can?t really see what it is. From its size and shape it looks like it could be a relay, but then it could just as well be a capacitor, or just about anything else. Markings on the protruding side do not indicate values one could associate with any particular component, but it is cracked to hell.
Now can someone tell me why I have to have CV joints replaced every year? The boots get torn, and the joint loses its lubrication and gets contaminated. That part is easy to understand, but why do the boots get torn? I do not drive off road or on gravel or any other harsh condition, yet I am constantly replacing CV boots, then sooner or later the CV joints themselves.