Volvo Repair: My poor 240 DL wont start, fuel pump relay, 4 quarts

Question
I bought my 1987 240 DL from a dealership in Maryland in March. It had 128,000 +/- on it then, I have 139k now. I have noticed a few of the following things since I got it.

1.) She likes to idle possibly a little low when it starts, run a little, then stall out. I can keep her going by giving a little gas till it warms up. Colder temps = longer warm-up time for she stalls out. Basically driving it quickly after start up takes three feet. Gas, clutch and brake all at once to keep it going.

2.) Every once in awhile while running, more noticed at highway speeds, she'll just stall out. Just, stop, going 60, with the gas pressed. I turn the key, and we're good to go again.

3.) Similar to #2, at times, often at higher speeds, the gas pedal will lose pressure beneath it, basically, I can press it in, but no response, it actually slows down, like the accelerator is doing nothing. If I pop in the clutch, rev it a lil, it grabs back, and I can put it back in gear and go.

Today, I was going down the highway, and had slowed a little to get on a merging ramp to another highway, slowed enough to put it in 4th, and it did what I assumed was the problem I've experienced in #2. However, this time it did not start.
I will admit I am about 2k over for an oil change, and I assumed it was an oil pressure thing. I put in 4 quarts of oil. I don't know if that's horrible or not. I will take it to the shop on Monday, but if someone could point me in a direction for myself to do some work, that'd be great. I know that I am not the best on car care, I swear to the heavens I will never ever miss an oil change again though. Previous to this, it was all synthetic in it.
HELP!

Answer
Hello Patrick,  As for #1,sounds like the throttle body is needing cleanning and adjusting.As for #2 check the fuel pump relay,its date coded from Volvo and if 8/10 yrs.old replace it with a Volvo part.Its under the panel, under glove box,its white and the only one there attatched by a metal holder.Number 3,seems she still cutting off but becauce its a manual,the alt is still turnning and the dash lamps are not on.Because the key is still ON ,when you pop the clutch she re-starts.Lastly when she didn't restart the relay may not have activated.She only holds 4.3 qts,hope you did not double that.To check the fuel pump system electricals ,in nuetral 'bump'the key to start,don't actually stare her,the pump will make a buzzzz for 2/3 seconds .Do this repeatedly 7/8 times if it fail once  replace the relay,Make sure the shop knows Volvo.Thank you and good hunting!  PKD