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My list would be to check timing belt alignment -crankshaft *belt guide notches* and cam and intermediate shaft (distrbutor/oil pump) pulley markings to rear timing cover markings. You could also be dealing with a repeat harmonic balancer problem -with #1 cyl at TDC (crank pulley timing belt guide notch should still be aligned with rear timing cover mark) check the scribed outer timing mark with the timing cover 0 degree mark. Either of those things could explain your entire problem. Your AMM may or may not be an issue, but as limp home mode didn't restore half-normal operation then you have a problem elsewhere like the ignition system. Thus I'd be very suspicious of the Hall Effect sensor in the distributor -good for all kinds of bizarre running behaviour.
As an aside, pulling the AMM connector during running is not as likely to damage the AMM (not a ton of sensitive logic in there) as it is the ECU (only minimal surge protection for its miriad of sensitive components). Even then, the risk is relatively low, it's just that the ECU and AMM are so expensive to replace if they do happen to get fried. You have also learned that limp home mode is only enabled when the ECU can't see the AMM during starting only. Neither pulling the AMM connector during running nor having an AMM fail during running will trigger limp home mode. Limp home mode is only triggered when the primary signal from the AMM is missing at startup and that normally only happens when there is a disconnect or break in the wiring. A bit of an odd design perhaps, but that's how it works with the LH systems. So, when you see a stranded Volvo on the side of the road, offer to disconnect their AMM as that may well get them going without needing a tow. There are of course other things like 25 amp fuses under the hood, fuel pump and radio suppression relays and empty gas tanks that can just as easily stop an engine. If you're a bit savvy, you can learn roadside tricks to deal with many common problems and get your fellow bricksters going again -see the FAQ and search the archives if you're interested.
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Dave -not to be confused with a real expert
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