Can they predict failure?

[mikefocke]

I took my 01 S with 50k in for an airbag light service to HBL. Pointed out this was it's 4th visit (2 prior to me) for the same airbag light on issue. They said they would fix it for free! Pointed out there was a TSB relating to grounding, could they see if that had been applied to my car as could it possibly be the cause of the problem and not the seat belt buckle. Sure enough. But getting away from a dealer having spent nothing...YEA!!!

Of course, when they came out to tell me the good news, they said I was about to have a CEL relating to the oxygen sensors and they could fix it while I was there for $450. I asked how they could tell it was about to happen. They said while they were in looking at codes they noticed it in the softcodes. No information which specific code(s). I asked if it could have been caused by the MAF malfunction I had just fixed? They didn't think so. I elected to wait.

So the question is .... was this just the standard story to assure they got the required $400+ out of a visiting customer or can they really tell that something is going to fail? (I can see a code might exist that says that paramaters were exceeded at some time in the past but can they tell how frequently, by how much or how often?)

[nightghost]

I would recommend you to get a extended warranty .

They will charge you $1800 for 2 years and every garage visit you pay $100 only even if you car need a new transsy or engine.

For me after I had my transsy replaced. I bought extended warranty. And guess what !!!!!

2 000 more and my engine is gone.

[mikefocke]

I've always opperated on the theory that the odds are with me if I don't buy extended warranties on anything. When I buy the warranty, I'm paying them for the expected average labor and parts, their selling expenses, their administrative expenses and their profit. So on average, the amount I'd have to pay for repairs is really only a portion of the cost the warranty would change.

When I bought my second Boxster, I had the option to pick up the seller's extended warranty. I declined. So far, after 2 years, my average monthly cost for repairs has been $9. Had I paid the $3,000 for the warranty, I woulldn't now have the $3k in the bank plus investment income from it to help me pay for any repair to any of my expensive toys.

Your experience has obviously been different. But then I had a very thorough PPI done before I bought this car. And everything the PPI said I'd need I did need and nothing but an airbag light and a MAF that needed cleaning has surprised me. If I need O2 sensors, I'll do them myself at $120 and still be wildly ahead.

[Q-Ship986]

....So the question is .... was this just the standard story to assure they got the required $400+ out of a visiting customer or can they really tell that something is going to fail? (I can see a code might exist that says that paramaters were exceeded at some time in the past but can they tell how frequently, by how much or how often?)

I believe the OBD system stores "pending" malfunction information. For instance, the system doesn't immediately illuminate your CEL upon immediately detecting every fault. Many faults must repeat themselves, usually within a predetermined interval (i.e. cold starts, drive cycles, etc.). If the fault doesn't repeat within the designated interval(s), the system clears it.

--Brian

P.S. I don't think they can tell much about the magnitude or frequency of the "pending" fault. They are just stored code(s). To get magnetude or frequency, I think the car needs to be monitored real time, with "actual" values, using a PST2, PIWIS, or Durametric system/tool.

Edited July 29, 2006 by Q-Ship986

[mikefocke]

As this was at a dealer. I presume they had a PS2 on it as they detected it when looking to clear an Airbag warning light.