So yesterday night I did the usual oil change on my car. Everything was ok until I tried to move my car. Rpms were going up and down, not very severe but noticeable. When they dropped down it was longer than when up. The car was leaning out very far, farther than normal. Sometimes is came to a sputter and once it died. It was running like when you first start the car and the AMM is unplugged. I checked but didn't notice any hoses loose. I replaced the AMM about a month ago. Fuel filter also. Could this be the fuel pump? Any suggestions would be great.

Thanks
Ben

ok, so I drained out the 10w40 and put in 10w30 today in equally cold weather to come to the same problem. The car started perfectly and ran for 3 seconds and then died. Restarting the car yielded the same results. I started it and got it to run by keeping the idle at around 1200. When the car had ran for maybe 20 seconds I let off and it kept running. The air/fuel mixture usually bounces back and fourth as the car is regulating but it does not do this now. It stays very, very lean. I shut the car off and now it will not restart. It turns over and almost starts to catch but will not. ANY HELP WELCOME!!!!

Thanks
Ben

I think I realized my painfully obvious mistake. I just moved from California where we had warm weather to Washington where it has been freezing and snowing. I put thicker 40wt in that I had been using and it’s just too thick for this cold weather. Guess I just wasn't thinking when I did it late at night. I am going to drain and fill with 30 later. Thanks again.

You were using straight 40wt, not a multi-viscosity like 10W-40?

In Washington, I would definitely use a multi-weight. 10W-30 should be just fine. You don't get hard freezes there, do you, like teens and below? In real cold climates you might want 5W-30.
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'84 '285' rice-eater with lotsa hp & performance goodies

I used 10w-40, but I am going to 10w-30. It is not usually in the teens, but in the low 30's - 20's at night. I checked with my brother who lives here and 10w-30 seems to be fine. Thanks

If you were using 10W-40 and that ran fine and now are using 10W-40, then the different oil is not causing your problem. When the weather is cold, the lower viscosity number is what matters; it's the number that tells how thin the oil will stay when cold. The higher number tells how thick the oil will stay when hot. So your lower number - 10 - has not changed and thus your cold weather performance should not be affected either.

Perhaps there is some other temp-related sensor on your car that is showing its weakness now that you are in colder weather. I have a Ford motor in my brick, so I'm afraid I'm not very knowledgable about Volvo motors.
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'84 '285' rice-eater with lotsa hp & performance goodies

Is the dipstick pushed all the way in? ( vacuum leak)
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-------Robert, '93 940t, '90 240 wagon, '84 240 diesel (she's sick) , '80 245 diesel