I think things are finally coming together. There is still the gas tank to install, but I am having too much fun driving it to take it off the road for a week or so, which is how long I expect it will take to get the new plumbing, fittings, wiring, etc installed. The car ran pretty well, in spite of its problems. The problems only became critical when it got cold. So the cold weather, and the continued very cool Spring forced my attention to solving the problems that were evident. I am really glad I kept to it, and found the problem. I wonder if a good repair shop would have diagnosed and found the problem right off. Because of my problems being created in the first place by a repair shop, I was reluctant to go that route, chosing instead to pull much of my remaining hair out as I plugged through the process of brainstorming this thing.
Anyway, The car still does not start up on the first crank, but it always starts on the second crank, and I am gaining confidence in it daily. It runs much better, and reminds me of the car I fell in love with years ago. Here is a brief rundown on the fixes.
Biggest problem was ignition. All along the way. The main wiring was not up to speed, the ignition switch was intermittant, and the coil was bad.
1. I bypassed the ignition switch with a relay-fed fuse box under the hood that is hot when a toggle is thrown.
2. I upgraded all the wire sizes for the B+ both switched and unswitched with new wire. I went bigger and better everywhere.
3. I finally changed the coil when it seemed as if the problem was still ignition related. This was determined by the fact that starting was so unreliable. I could always smell gas, and it would not start reliably no matter how I tuned the start coefficients. Once the coil was changed, the nature of the car changed dramatically. All the fuel map was now rich, even though I had carefully tuned the map with the old coil to READ 14.8:1 with the wide band gauge. Apparently raw fuel resulting from misfires was giving the AF ratio gauge a faux reading, tricking it into thinking the mixture was lean, so I was making it too rich to get it to read right.
4. I tightened up all the grounds. These seemed fine, but you never know. The main ground cable from the battery, which is in the trunk has a large 100 AMP fuse in the line what is held in a fuse holder that was not completely tight. I may replace that with a better set-up. I simply cranked down on the bolts a little more. I could also improve it by soldering the fixture together and not count on the mechanical connection to carry the load.
It seems as if good tuning is now possible, and I am working on that as time and energy permit. The car feels much better now than it has felt thus far with EFI. I need to round up a buddy to drive it for me while I fiddle with the laptop. The starting needs to be tuned better, but I am getting to where I don;t worry quite so much about getting stranded. I guess I should feel lucky that this coil did not die completely somewhere away from home. But if it had, at least I would have known what the problem was earlier on. The bad coil did lead me to improve everything in the system looking for the problem.
I am still open to the possibility that the MSD box might have a temp sensative breakdown of some kind.
The bottom line is ALL the so-called-problems with the EFI were traced back to things that had NOTHING to do with the EFI itself. The problems were all in basic, fundamental, old fashioned, low tech stuff. The thing is, and this is important to all you guys out there with carbureted cars as well, the car ran fine with most of this bad stuff when it was carbureted. The interelated nature of the different systems was not as critical with a carb. That does NOT mean it would not have run better with the carb if I had fixed the wiring, the ignition switch, and the grounds. Its just that as long as the car does not break down and leave us stranded, many of us are happy to simply make do,and carry on with sub-standard wiring in the car. It if runs, then all is assumed to be fine. But just because it runs, does not mean it is as good as it can be.
I have been saying for years, and this is the real irony here, fix your wiring if you want to improve your car. All the fancy hardware, and high tech upgrades are pretty much wasted it the electrons don't flow as well as possible. I will come down even harder on this in the future.
Thanks for all your help so far. I am on the road to recovery for sure, thanks in large part to the support this group of great guys have given me.
Sam
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