[Shiny]

Originally Posted by dataway

The purple wire on my car only shows signs of heat at the connection points.

Tnx for clarifying. And you are going to solder your crimped connections!

I think Roger mentioned that there WAS a service bulletin concerning that wire, not sure if it included a relay .. probably not as it was not seen on the 69.

I missed that but see he updated. As to a relay still not used in 69, I'm hoping someone can share "when" this starter design was changed.

...
I guess we would have to define "longevity" since I seriously doubt GM gave a crap about what happened to cars 10 years after they built them.

I don't know how much they cared, but clearly not enough to spend what it would take to make them issue-free for all customers in 10 years!

My experience in reliability engineering (again, not autos) is design orgs establish a "design life" or "useful life" for the product but may not spend the money to prove it nor guarantee it. Maybe a 10-year number is a good example for this discussion.

Allowable failure rates during the warranty period are basic requirements for new products. These are "reliability requirements" (specs) just as much as functional design specs. The 12-month/12K miles in 1968 might be an example. Other failure rate targets may be set beyond the warranty period depending on the business. A new product would have to "prove" they met the warranty targets before shipping to establish confidence in the planned warranty cost. "Proving it" translates into lots of time, money, and risk.

Probably the only upside to EPA regs on modern cars is that they require so many parts that are considered part of the emissions systems to be warrantied for longer periods. Seven years I think? Which probably drove GM to improve components and wiring that otherwise might have been marginal at that age.

We won't debate the "only upside to EPA regs" on this forum but yes, meeting regulatory standards that require increased reliability can be a burden if the business otherwise doesn't need that to meet its goals. And yes, the consumer may benefit in other ways (like more reliable wiring) but they also pay for it.

Bottom line is "what's good enough?" for a lot of these decisions. IMO, any business that can actually answer that question is a good one and it makes product development easier.

Originally Posted by roger1

The service bulletin was to add the relay to address the no-start situation due to the heat soak on the starter/solenoid. It was a retired Chevy rep that stated that in a forum I was reading. Don't know if there was one for Pontiac or not but the issue was GM wide since they all used the same starter/solenoid design. It worked because it boosted the voltage to the S post on the solenoid.

Thanks for this. Did the relay replace the solenoid high-current contacts (like the diagram posted earlier in this thread) or did it just bypass the source of the "heat-induced" voltage drops?

Mike