Hello group,
We acquired a 1987 760 Turbo wagon last year. Just under 160,000 miles, seemingly reasonable shape but no promises made. Had been used for mostly short local trips last few years. A sticker indicates that the belts were replaced at about 150,000 miles, a year earlier.
Early last year, the car failed to start for the previous owner at 156,800. Mechanic replaced fuel pump relay, fuel pressure regulator, cooling temp sensor and distributor ignition assembly ($276). In May, the car failed to start again, just after doing over 200 highway miles. Another mechanic found engine block soaked with gasoline and cleaned everything up again. He replaced the fuel pump ($213) to try to solve the flooding problem.
The next day, the car passed state inspection for safety and emissions. A high point of our turbo brick ownership to date. A week later, it was dead in the driveway again and this time we towed to a Volvo dealer.
The dealer mechanic also found fuel pouring out of the cylinders - stopped when injectors were unplugged. He checked compression and found all cylinders over 140 psi. They spent a lot of time checking ground wires and cables and repaired several shorts. But still no clue on the fuel problem. So we bit the bullet and replaced the Electronic Control Module ($993) and car left dealer running well.
In the next six months we drove another 2,000 miles or so, mostly short trips, some highway. But with the onset of winter it started dying with growing frequency and now it's reached the point where I haven't made it out of the neighborhood in two weeks.
When left to sit for a time, the car starts quite readily but will die within 35-45 seconds. If I do manage to get the car warmed up and try to drive, it lately tends to die suddenly while in motion. When the start-die-restart process is repeated too many times, the car refuses to start at all as if flooded -- yet I don't smell gas when I stick my head under the hood. Part of the problem is when the idles speed swings up and down "searching" it tends to die at the low end of the search. But that happens less often than the engine just quits with no provocation. And that seems to be happening with increasing regularity.
The question is what to investigate to find the cause of this. I have acquired a shop manual and begun getting familiar with the basics. I would like to make this car run well enough to do at least a few more thousand miles of short trips -- it's getting to be a personal challenge!
Therefore, I would greatly appreciate the value and benefit of any guidance, suggestions, lessons learned, etc. regarding where I should start looking for a solution to this problem. I have read a lot of good advice here so I'm hoping for a bit more to help me target my effort. Thanks very much.