So my 745T decided to totally die on me last week, went to take off, gave it a full throttle, and a mild backfire later and all the power was gone.

It's done this briefly before, just gone into what feels like limp home mode for a while, bringing me to a halt, but then fixed itself.
But this time, it's fully stuck in dead mode, the car will idle ok, a little rough and looks a touch rich, but it won't make enough power to really get moving.

Anything more than just gentle throttle in park and it will cough and try and stall, it will rev just a tiny bit in park if you roll on the throttle a little, but in drive your accelerating about as fast as bicycle.

If you try and just floor it to make power, it just coughs and backfires a bit.

Current thinking is AMM, but I'm looking for possible alternatives, just in case it's not, I found one source listing almost my exact problem as AMM, but another quoting that the car should not run or idle if it is the AMM?
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Wagon Power, My 88 745 Turbo

The 745T is now fixed, had a delay on getting the AMM, the part number had been updated, my friend in fuel injection had to find it's replacement and order it from out of state.

Old part number was Bosch 0 280 212 007, and according to Bosch it's now been superseded or updated to 0 986 280 102 -9B9, both old and new part numbers were on the side of the box it came in...

Car runs great now, better than ever, the old AMM must have been junk, non-genuine and obviously just cheap, internally the two meters (old vs new) are very different.
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Wagon Power, My 88 745 Turbo

Well, anymore guessing is probably no longer necessary, I pulled out the AMM tonight and had a good look, the filament wire is broken, which I assume means it's defiantly broken...

It's not that old, but then it's also non-genuine/non-bosch, and rebuilt as well by the looks of it, probably not a good sign.
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Wagon Power, My 88 745 Turbo

Hmm, well my Volvo guy suggested a little test to see if it's the AMM, which he thinks it is, so I tried it today...

Start and run the engine, let it idle, and then just slowly try to rev the engine, then do it again but now pull the plug from the AMM just as you start to rev it, if it's builds revs better/quicker once the AMM plug has been pulled, it again suggests that it's at fault.

I tried it, and sure enough it did rev a little easier/quicker when I pulled the AMM plug.
So it look like I'm still looking at AMM failure, which I hope will fix it, as it's a expensive part to replace if it's not...

IPD suggest another small test on their site, although I'm not sure about it because it seems a little inconsistent, but it does seem to almost stall when you plug the AMM back in, but not every time.
Sure would be nice if there was just a straight forward yes or no test result that showed if it was crook or not for sure.
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Wagon Power, My 88 745 Turbo

It is bad practice to unplug/plug in an air mass meter with the car running. It will sometimes fry an otherwise good AMM.

One thing you might look at is the possibility that the backfire caused the timing belt to jump a tooth. Easy to check; simply set the crank on the top dead center mark and peak at the cam spocket to see if it is on its mark.


Randy

Really?, cause there are several or more sources all telling you to do that in various ways to help find if it's bad, including my mechanic, who used to work for Volvo...
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Wagon Power, My 88 745 Turbo

I'm not a Volvo tech or a professional mechanic/electronics person- I am only passing on what I have heard from several sources as well.

Randy

Mine '86 760T did the same thing about .5 mi from home. Just wouldn't go but would idle. I unhooked the AMM and drove it home and it ran perfect. I parked it out back and now want to get it running so I can sell it. When I plugged the AMM back in, it went to same bacfire no power.
Good luck and I,ll be interested in what you find.
Ray
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'94 850 wagon, '86 740 GLE, '88 740GLE, '86 760T that may go, '80 240 DL wagon and '81 240 DL that need to go.

Aside from the mass meter check and make sure that you have not blown any hoses off, I've seen that one a few times and especially after a backfire.

Mark