I have a 98 V70 non turbo. 246k miles
I started it last evening and it quickly stalled and wouldn't restart.

Today it will fire occasionally but will not start. There is spark at least on one of the plugs (haven't pulled them all yet) and it appeared to have fuel on it.


After cranking it and a few firing a few times there is a buzzing which I believe is the idle air control valve.

Timing belt is not broken.

So what is the next thing to look at see if the timing belt jumped a tooth?

belt timing was ok
Finally got it to cough and sputter to a start and it was running super rich.
Then I realized it must be Mass air flow sensor, unplugged it and it ran better.

Here is another question though. I replaced this 2-3yrs ago with a Bosch unit.

is there something that would make this go bad this quickly?

Yes. The thermostat, solenoid, for the pre-heat air can fail and cause heated air to always enter the air filter box. This very hot intake air will destroy the MAF. Regardless of your climate, you should force the pre-heat air vent to be closed at all times.

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My name is Klaus and I am a V♂lv♂holic

I cleaned it with sensor cleaner and it seems to bebetter for now.

Is the preheat air vent in the bottom of the air cleaner box?
what is the best way to force it closed? does the thermostat need to be disconnected?

Do not disconnect the thermostat, that will give you a check engine light. Yes, the bottom of the air cleaner box, where the aluminum tubing goes in.

There is a nice pic on matthews volvo site, where someone inserted two pieces of a wooden dowl rod to keep the flap closed. Duct tape tends to dry up and fall off.

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My name is Klaus and I am a V♂lv♂holic