B_2

The real question here, is what we can expect from an electronics test at the Porsche shop?
i.e. All possible values! Pending and/or confirmed codes from the diagnostic port on a late 944. Does it actually stores them at all?

Left my -91 944 S2 to the local Porsche shop the other day. The car has been running really bad a couple of times, (misfiring and stalling) especially it had proplem efter i washed it.
I don't want to just throw random new parts on it so i wanted them to test it first. (This is at the big fancy Porsche dealership in my town).

I specifically ask them to hook it up to the diagnostic tool, (i.e. "the Hammer"9288/KTS-300 or equivalent tool they use nowadays, it might be the PIWIS?, or what else?)
Picked up the car yesterday and they done nothing other than a "hands on inspection" which resulted in a cloth wipe out of distributor cap and a "smoke test" which actually confirmed a crack in the 90° pipe attached to the air guide tube between Throttle body and MAF. Fine! But nothing i wouldn't have figured out on myself!
They didn´t have the correct cable at hand and i dont know why they didn't contact me and resceduled by now? Neither did they wet it down at all before testing, which i asked for.
No electronics was hurt during this process! (pun intended)

Then i had four young men essentially telling me what a teacup is when i actually was asking for what the contents of the teabag inside of the teacup was holding. (pun intended again) I did not respond well to this discussion. The mechanic at hand said it wasn`t going to tell anything special?
Ehrm... You Have No! Cable at hand!
On the way out i discovered that they scratched my spoiler/fender in the process! (Loyal customer service i presume)

So, what are your insights to the matter? What can they actually read from the diagnostic port?

walfreyydo

Dude, the diagnostics test kit is like lost tech at this point. The odds they will have this 33 year old tool is not high. Did they confirm they actually have that tool?

Fortunately the car can still be diagnosed the old fashioned way (like most 944) and vacuum leaks are one of the top things any shop is going to check first. However, it is unfortunate if they damaged your car and they should compensate you for it.

Also, mechanics usually dont respond well to customers telling them how to do their job (like telling them they need to use a 33 year old diagnostic tool instead of alternative/normal diagnostic testing procedures, or how to do their diagnosis), and usually doesnt lead to good outcomes. You kind of have to let them do their work and if they cant fix it, take it somewhere else (or my preferred method, do it yourself). I agree with what your mechanic said, the diagnostic tool isnt 100% needed to diagnose these cars (but I imagine it helps), and they probably didn't have one and figured they don't need it to fix your car.

They probably havent called to reschedule because they probably dont want to deal with you.

If you would rather take a crack at fixing/diagnosing the car yourself, Clarks provides a good step by step guide
https://www.clarks-garage.com/shop-manual/ts-01.htm

Sorry to be harsh

B_2

I specifically asked for, and did get a initial promise that they would test the car via the diagnostic port whit a diagnostic tool, i.e. the modern equipment they have nowadays, (my guess is Piwis).
Also promised was to give the car a wash to figure out of if water would cause the problems. They didn´t wash it.
You are probably right about their unwillingnes to handle old cars, and their owners.
But they accepted the job, didn´t do what i ask for and damaged the car in the process.

jhowell371

Was it a Porsche Dealer or a shop that works on Porsches? When my S2 acted up it was the O2 sensor making it run poorly. YMMV

B_2

I have read som treads about the O2sensor problems including one where a damp sensorharness was the culprit. Read your O2-tread just now and it´s absolutely on the suspectlist.
And that is also what i would like to find out from a test.

Steve Pratel

Right off the bat, running issues after a wash indicates a cracked distributor cap or bad wires. Water and electricity don't mix well.

You're wasting your time taking your 30 plus year old car to a dealership. Best that is to find a local shop who specializes.

One final note, most service shops do not like being told how to do what they do, Even though my experience 99% of them have no clue what they're doing which is why I do all my own work unless it is warranty related. For the most part the dealerships are inhabited by shaved apes.

jeyjey

I think it depends on how invested the dealer is in you as a customer. I have a 2002 Vanquish that I send to the dealer. While that's 20+ years old instead of 30+, it's still well outside their wheelhouse. But they make a good effort and get it right in the end (occasionally after several trips). I think the difference is that they've been seeing me and the car for 15 years.

Zirconocene

There are madmen out there dedicated to keeping these cars on the road. To wit: https://928-ecu-repair.com/diagnosetools_udt999.html

No affiliation, and I have mostly learned about it on the 928 forums, but there is capability for the 944 and 968, as well, so maybe this will help you.

Cheers