George > wrote
> wrote
>> George wrote

>>> I was driving at highway speed on the Interstate on a busy Friday
>>> afternoon when the engine simply stopped. Fortunately I was in the far left
>>> lane so I was able to coast off the road without cutting
>>> thru traffic. I had the car towed in to the garage. It started and
>>> ran OK. The computer did not have any stored codes. They
>>> eventually found a failing crankshaft position sensor.

>> the engine would not re-start out on the side of the Interstate,
>> but would after cooling down? MIght have been a thermal effect
>> which may recur some sad day.

>> I am not one who automatically presumes dishonesty on the part of service
>> vendors. But I also will not automatically presume that a successful
>> "repair", is a the same as a "cure". There's an old saying that "a conclusion
>> is where you were standing when you got tired of thinking". For example, did
>> they subject the position sensor to a battery of tests, *in a test jig
>> outside the engine*

> You do know that is completely ridiculous.

We'll see...

> The failure that the car had could have been caused by a number of components.

Correct, but he is talking about anticipating the failure, before it happens.

> It is totally impractical to remove all of those components and perform some
> sort of exhaustive analysis on them.

He doesnt appear to be saying that is done, just
that the test system is outside the car. In other
words it checks those components while they are
still in the car. Thats possible with those sensors.

> And more importantly it is outrageous to perform periodic testing on such
> components because it typically does not produce a reduction in failures.

Really depends on the percentage of sensors that go bad
other than instantly. In other words whether its possible to
detect some going bad before they fail completely.

> Instead the mechanic performed a reasonable and customary repair. He plugged
> his analyzer in and went for a ride until the computer
> produced a service code. The service code was for a specific sensor.
> He replaced the ~ $40.00 part and the car has worked fine since.

And that appears to be what Alan is talking about.

> What else exactly needed to be determined?

What has failed.

> The Space Shuttle level inspection/maintenance process you advocate just
> doesn't make sense for a passenger automobile.

He appears to just be advocating the use of the analyser to
pick up imminent failures before they make the car undrivable.

His claim that its possible to completely
eliminate all failures is clearly just plain wrong.

> And even with the extreme level maintenence the shuttle does have problems.

For different reasons tho.

>> You're happy because they fixed the complaint within a reasonable
>> budget. THat's a very normal & rational thing. We should not mistake
>> their actions for a complete diagnostic work-up.
>>
>> A real diagnostic work-up for evaluating a vehicle isn't easy to
>> find.... it takes LOT of expensive equipment, and a learning curve
>> for the mechanics. Money, and more money, which could only be
>> recovered by charging for... no repair work. Bev, over in another
>> thread, already displayed a VERY typical consumer reaction to such
>> an offer: "I don't want to pay for information about the mechanical
>> condition of my property". She is really in the center of the Bell
>> curve. How many people get their homes inspected outside of a
>> trying-to-sell situation? How many people keep even the simplest
>> track of MPG or of (eg) battery specific gravity, or condition of
>> crankcase oil? THese things are quite cheap to do.
>>
>> Go into any auto-parts store and look at the tremendous number and
>> variety of after-market products which cater to activities which
>> enhance the COSMETICS of a vehicle. They get the shelf space because
>> they have a high profit margin (ie, the chemicals involved are not
>> spectactular, but they've been marked up spectactularly); and because
>> they move well. People get pleasure in burnishing the appearance of
>> their vehicles. I don't see many people blueprinting their engines,
>> or the auxiliaries.
>>
>> It used to be that the AAA of Massachusetts owned and operated an
>> actual Diagnostic Center. You paid a few hundred dollars for a
>> top-to-bottom evaluation of your vehicle, by Master Mechanics using
>> the best instrumentation... no repairs, you paid for RELIABLE
>> INFORMATION. I don't know if it still exists.