In reply to rslifkin :
That is exactly what is "wrong" with JaguarV12's the lack of OBD2 on the computer. In theory it's a very simple system but without a broad base of knowledge ( an average of 2700 V12's a year came to the US ) mechanics are working in the dark. Well that and no EPROM means modifications involve removing the boards and soldering new resisters etc in.
Going to Replacement ECM's like Megasquirt is complicated because most sensors are analog not digital and that's like speaking Chinese to an American mechanic. It doesn't work well.
Then there is the final complication. two throttle bodies.
rslifkin said:
In reply to RichardSIA :
If you've ever got a reason to buy a computer based car in the future, shoot for 96 or newer, up into the early 2000s. They're no more complicated than the older ones, and in some cases simpler (as they were able to simplify some of the vacuum driven emissions stuff, etc.). But more importantly, the ones in that range are MUCH easier to diagnose. If you ask them correctly, they can often point you pretty close to what's wrong. The early computer driven stuff was still somewhat in the learning phase.
I remember being 'afraid' of OBD2. Lot's of problems in the early years with stupid stuff. CELs from loose gas caps, etc. Now I can't imagine life without it.
One of the things I love about my '19 VW is that for $200 I was able to buy a cable and some software (VCDS) that lets me do 90% of the stuff a VW tech can. I can look at every engine sensor and log it at up to 20Hz. The first aftermarket tune I put on the car had a funny stumble off idle. Rather than a bunch of back and forth, I provided a log. "Start looking at cell XXX. My foot doesn't move but over 300ms, the RPMs drop, then come back". It's not just the ECU, it talks to all the different little computers in the car. Awesome stuff.
In reply to mfennell :
That's exactly what is needed. We have a lot fewer trained mechanics than monkey see monkey do or just parts replacers.
When I worked at a gas station we had a whole wall of stuff with dials and screens etc. we'd plug a car in and it would take 10 minutes once we got the hood up and that was once we learned what each connection did and what it needed to be connected to.
Oops see here Mr Jones. Your #6 & #3 plugs are fouled and your points have too high a resistance. Oh and your generator needs the brushes replaced and the commutator cleaned. That will cost you $56.15
Hmmm that much huh? Maybe I should just trade it in. It's already almost three years old.
In reply to frenchyd :
During one of the stages of the Targa Newfoundland, the engine went soft right when I crossed the finish line. Plugged in the OBD-II scanner, it said coil 1 was bad. Swapped it, raced for four more days. Elapsed time for diagnosis, about 2 minutes.
In reply to Keith Tanner :
Amen. It's funny, the 1996 Jaguar XJS V 12 had the same reliability rating as the Six but the year before without the OBD2 the V12's rating was horrible.
In reply to RichardSIA :
You could advertise it as the miraculous self healing car of GM.
