Shifted wrote: ↑Fri Dec 04, 2020 7:48 am
I remember reading that thread thoroughly, and looking at all of the photos. To be honest, I don't think the cause was as innocent and universally applicable as the business owner made it out to be. My personal opinion is that it was due to negligence of the shop, not anything inherently wrong with the 928's design, vehicle age included.
I posted to that thread with some observations of how the front main harness is often misrouted.
Also, 'round the same time I had just installed a brand-new-out-of-the-Porsche-bag engine bay (light) harness. The NOS is remarkably cheap for what it is. Reminds me that I need to pickup a spare for my '91 while they're available.
In any case, with everything correctly routed, in my opinion, a car fire caused by the light harness or front-main harness is effectively impossible.
My bet is that that car, earlier in it's life suffered collision damage in/around that area and the harness was either damaged and not replaced, or damage wasn't noticed, or was improperly routed/installed during the work.
I have seen with my own eyes, too many times, how body shops 'skip' things or just plan fuck things up.
Hey_Allen wrote: ↑Fri Dec 04, 2020 11:54 am
That said, I have found degraded wiring on my car, with insulation just dissolving or cracked and crumbling off, so I'm not going to totaly lay the blame on the shop.
This too. I have noticed over the last 5-ish years that all of the wiring harness on 928s brought to me are very brittle. I take extreme care to perturb them only as much as needed and every single time I see cracked insulation on a power lead I deal with it.
Now, as far as insulation just 'disintegrating' on 12v leads, this I have yet to see except for the front main harness. That harness gets the most 'abuse.'
The jump post area and ABS terminal area always get an inspection on a new-to-me 928.
Shifted wrote: ↑Fri Dec 04, 2020 7:48 am
How many others like this have you heard of vis-a-vis failed fuel line fires?
I am of the opinion that the majority of fuel fires are the result of poor work(*) just prior to the fire. Or, in other words, 100% of fuel fires after fuel system related work are the result of poor work. I believe that there have been fuel fires due to three-decade old fuel lines releasing fuel however, I do not recall a credible story being posted to the other site.
I, once, a long time ago, received an S4 on a flat bed. Long story short, after some repair work, not fuel related, I took it on a test drive for evaluation. One result of that evaluation was an intake refresh. When I went to remove the intake as I was wiggling it up, I started smelling fresh fuel. After investigating I discovered that the return line from the regulator had a crack in it such that every time the motor rocked side-to-side a drop of fuel would escape.
A couple of things I learned from this:
- check your fuel lines often once they are 10 years old
- a drip of fuel isn't an instant engine fire
- when you do motor mounts be damned sure your supply and return fuel lines are in really good shape
- if for some reason you get a 'new' 928 into your possession, always inspect the fuel lines. And I mean the part of them you can't see. With an inspection mirror. And wiggle them.
(*) Poor work seems, IMO, to be lacking in one or both of these:
1) Always, always, always, do a long careful leak check by bypassing the FP relay as soon as you 'button up' the fuel system.
2) Fuel injectors go into the rails, then the rails go into the engine. Never, ever, ever the reverse.
Hanlon’s Razor: Never attribute to malice that which is adequately explained by stupidity.
Heinlein’s Corollary: Never underestimate the power of human stupidity.
Worf’s Razor: Never attribute to stupidity that which is adequately explained by laziness.
Worf's Corollary: Once you've mitigated risk from stupidity and laziness in your endeavors, failure is usually the result of insufficient imagination.
My 928 Inspection Guide
- By Stepson