That's great to know about the OBD 1.5. I found comments about that last night on ETCG website. Now, where do I get one of those special readers? Beg, Borrow, Steal, or other methods.
I work with computers in my job. Confusers is what a lot of us refer to them as, especially when they confuse us.
The problem of not starting will happen hot or cold, at any time. When the engine chooses to start, it runs beautifully. You would not think there is a problem. But, you risk everything if you shut it off, even for a second, as it may not start again.
It cranks good, and I give the battery occasional doses of charge for a couple hours. This has been a problem for some time, but has been getting worse and worse, and more frequent. Now, it's so frequent that it's in my garage until I can fix it.
I'll give the shot of carb cleaner, or throttle body cleaner, into the intake a try. With good fuel pressure, I would think it would be ok, but it might be the injectors that aren't firing. It doesn't sound that way, though. It sounds like it is igniting, but I could pull the fuel pump relay, bleed off the fuel pressure, then compare the sound of cranking it with out any fuel.
All vacuum tubing looks really good. The "T" tube that the MAP sensor and the fuel pressure regulator shares is also just fine. It's a 3.1L engine. I think that some sensor somewhere is telling the computer to kill it. I might have to harvest a few of them from a junkyard, and just try them. Some are a bit to get to, but it'll be a learning experience. I just hope I bring all the right tools. The MAP sensor cost me about $50 new, instead of $5 used.
Is there any way to fake the computer into starting it?