Here's what I've found on the 1998 s70 glt turbo I owned some years ago which sported some of the same intermittent odd behaviors: 1) Every electrical connector to every sensor and junction point was pulled apart. I found a fair amount of corrosion and oxidation. I cleaned them with some electronics...

I've seen my own car do this but in a much more benign way. It's caused by (my theory) sitting around. The car needed REALLY frequent oil changes after I bought it and drove it semi hard for about a year after. The oil turned dark in about a thousand miles. In your case it looks like a hard dust and...

What do the plugs look like after a read? Normal wear or oily deposits?

I had a 98 s70 do this. It's the integrated power stage (switching node) and coil. Go to a boneyard pull a replacement unit and test. Check your grounds all along the way. To confirm meter your ignition coil separate from its power stage. Refer to spec. for the ohms (coil to ground, coil to coil, gr...

Of course I'm interested as I've done full restorations of these though I'm down in Florida now. It's too bad. I wondered about this box since i saw the post here. It could start another where my 764T is about to finish and it certainly deserves a better home than a boneyard. What's it need? It look...

Though I couldn't say how that market behaves I can say that if there's a way to avoid it becoming scrap do it. These are valuable cars here; there's one other in my area that passes around through hands though the catalytic converter is scrap. Best one made in many years though like most other part...

I have owned several 740s, the last was a 1990 m47 5 speed sedan. I owned the 850 wagon before that and the moral of this story is: If you get that 740 hang onto it as long as you can if it's straight without rust and has good mechanicals. I have a 764T now that I've done a lot of resto work to late...

Those Regina no starts after what you describe sound much like the classic RSR death. That relay is prone to solder joint failure and yes it's easily repairable. I didn't see a reference to it in your description though if you did check that my bad. Do look and see if you can open the diag connector...