Hi, all!

1998 V70, a little over 240K on the clock, non-turbo, front wheel drive. The car will idle for about 30 seconds, could be up to a minute, and then entire body will shake violently, rpm will drop to 500 for a second or two, and engine shuts off. Any ideas, clues, possibilities? She has been extremely reliable, with virually no problems. Any and all info is hugely appreciated!

For those keeping track and/or are curious, it was the mass airflow sensor. A highly reputable independent shop stated that it was the oil from K&N filter that caused the failure. I am wondering if anyone else had this experience...I had K&N in the car for close to 200,000 miles without any problems. With a litlle over 240,000 on the clock, is it about time for mass airflow sensor to fail anyway? K&N's website has a sizable (and to their credit) well documented list of mass airflow sensor failure cases reserached. I am at a loss, mainly because I love not having to buy air filters every 20,000 miles, and it improves gas mileage in my observation, but having to pay over $400 for diagnostics and repair sucks. Any thoughts???

Your MAF did last a long time, and I wouldn't blame the K&N filter directly. The problem with the K&N is when it is cleaned and re-oiled. Some people use too much oil and that will atomize and coat the MAF.
When my K&N filters got dirty, I just replaced them with new. Then, I never go down dirt roads and seldom encounter dusty conditions.
There is also nothing wrong with paper filters, so long as they are replaced regularly. My Dad caught me once trying to vacuum clean my Volkswagen filters and I will never do that again!

Your new MAF will run for another 250K miles. Hopefully, next time it will be an easier diagnosis.

Klaus
--
Common sense trumps a PhD

If you still have the original fuel pump @240K, that's a pretty good guess.

-BTC

'98 V70 T5 181K mi., 5-speed manual, original (noisy) clutch, heated velour cloth comfy chairs, factory HD suspension (1998 only), Bilstein HD, front IPD stabilizer bar, Volvo strut tower brace and skidplate, XC grill, C70 jewel E-Codes, V-1, Lidatek, IPD stuff, JB Weld, Original Duck Tape, zip-ties, two Honda license plate nut impressions in back bumper (gift from daughter), Mobil-1 since new.

'08 BMW 328iT 6-speed manual; my new stickshift Volvo station wagon substitute :(

Yes, my fuel pump is original, and I was thinking it could be it as well. Thank you all for your replies!

If there are no diagnostic codes, then it could be fuel related. Check the fuel pump relay and the fuel pump. Start the engine and and be prepared to push in on the schrader valve at the end of the fuel rail. As soon as the engine dies, take a phillips screw driver and push on the valve. Make sure you have a shop cloth handy to keep fuel from spraying around, just in case there is pressure :)

If it is not fuel, then you should pull a spark plug or two to check if they look clean or wet. If wet, you have a huge vacuum leak around the intake manifold.
If dry, it could be the cam position sensor. But, that usually sets a code.
--
My name is Klaus and I am a V ♂ lv ♂ holic.

Is the car a turbo or not?

I'd look into changing all your vacuum lines.

If it's a turbo clean out the PTC nipple on the turbo intake hose (lots of posts on this I think).

If it's not a turbo, remove the flametrap screen from the hose that goes into the intake (lots of posts on this I think).

This could also be a MAF sensor (Mass Air Flow). Do the vac lines first - it's a pretty big job and will take some time but it's well worth it. Remove your battery and breather box to get access to the space alongside the head above your transmission.