Trivial observation about cars and ECMs

[Shannen Durphey]

Hold on here!

Nobody, but nobody, has asked what year cars/what ecms?

165's had an extremely high failure rate.  727's mounted in Luminas also had an
extremely high failure rate.  747's in fullsize vans had trouble for many years. 
Some cars are much more likely to lose an ecm than others, for example the 82
Corvette where the ecm is mounted in an enclosed battery box.  My experience has
been that different parts of the country tend to be different regarding ecm
failures.

Anyone working with ecm's/pcm's now has likely forgotten how much trouble those
blasted boxes caused in the 80's, and in many cases, up into the 90's.  The 165's
had bad solder joints, the coolant fan drivers would fail, the injector drivers
would fail.  Failure of the component on the output side would kill the ecm.  A
simple EGR solenoid failure would often show up as a quad driver failure before the
an egr code.  727's would spit and sputter, often failing to run.  Tapping the case
would straighten the problem temporarily, and a new ecm always cured it.  

I am still replacing 165's in GM cars, and I only use GM reman ecm's.  Newer design
ecms fail much less often, but they still do.  I was surprised at finding my first
bad 8051 last summer, but 2 more showed up right after that.

If I were stripping ecms and reselling them, I'd worry about the units coming back
as non-working parts.  Maybe I'm a little biased from the days when ecm's had
shorter life spans, but I've got good reason to be.

Funny how the techs were the first guys to say the problem lies with the techs. 
Makes one wonder what kind of business we're in.

Shannen


Gonyou, Jeremy (.) wrote:
> 
> I think you hit the nail on the head.  I worked with a guy who used to work
> at a dealership.  If someone came in with a drivability issue, the ecm came
> out.  When the factory asked for the "bad" ecms, they rigged up a jig to run
> 120V through the pins...
> 
> Jeremy
> 
> Having parted out another car last weekend, I couldn't help but notice
> something.  Seems like nearly every car I get to strip down has a
> remanufactured ECM in it!  It's uncanny.. I'd have to guess that about 8
> of the last 10 cars I've parted out did not have the stock ECM.  Anyone
> notice a similar trend?  I can't believe that the stock ECMs had such a
> high failure rate.. Could it be that ECMs have a bad rap among service
> techs, and automatically get swapped out when a car comes in with
> drivability problems?
> 
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