I've got a 1983 Volvo 244 DL, it's got LH2.0 and Chrystler ignition. It's got one of those really bad stall problems that these cars seem to get, and it's been developing for about 9 months now. Before the car stalls, I can hear one of the fuel relays (or maybe even both) click. It's completely random, doesn't matter what my speed is. Sometimes the car bump-starts itself back on, if not I can throw it in neutral and re-start it right away every time. The relay/relays themselves are not the cause of the stall. Sometimes it'll go for weeks w/o stalling, sometimes it does it every 30 seconds for weeks. Also, when it stalls the tach follows the engine down. Here's what I've tried/replaced:
I've tried a ton of different fuel pump and system relays and also bypassed them. I replaced the engine wiring harness, ECU, coolant temperature sensor, coil, and rotor. I replaced a cracked soft line in my in-tank pump. I bypassed the ignition switch, and that didn't fix it. I also tried unplugging the IAC and TPS, car still stalled. I did the same thing with the AMM, although I'm honestly not sure if it stalled because of the usual unknown cause or because of the rough idle from 'limp home mode.' There is a bit of flashover at the coil tower to both the + and - terminals, although the coil and wire are both very new... I can't find any vacuum leaks. Often the stall can be caused by taking a hard turn- it used to be left turns, but has now changed to right turns. Because of the normal tach behavior, this seems like a fuel problem to me. Is it at all possible that the ICU could cause this problem, since it does communicate with the ECU? I am really stumped at this point, I'm pretty much completely out of ideas. I've checked the grounds on the intake manifold and the fuel pump grounds. Are there any others I should check? The only things I can think of to try now are a new AMM, a new Hall sensor, and a new ICU, although none of these seems like a likely culprit. You guys are the best at diagnosing and always seem to have a good sense of how to fix these kinds of problems, so are there any ideas out there? I really want to enjoy my brick again:-( Thanks!!!