I just got an 86 740 gle sedan, 4 speed manual. It starts after a minute of cranking, then wants to die if I don't keep my foot on the gas. When it gets warm it idles, and when I drive it has very little power. Especially at lower rpms. I took the air intake apart and cleaned everything out and checked for leaks. No leaks but it was very dirty. Air filter looked okay(could easily see sun light throug it) I'm wondering if maybe this could be a bad fuel filter/one of the fuel pumps may be bad? I hear these volvos have 2 pumps and will work wih one but not well....

Anything helps. Free car, barely drives. The price is right? maybe not...

 

Sounds like classic fuel starvation. Check the fuel pumps and the filter. You should hear the pump whirr momentarily when you turn the key to run but not all the way to start. You might need a helper to listen.
Andrew

 

the Bosch LH FI systems will run with just the main pump, they won't run with just the tank pump. if the tank pump is out, the main pump strains when your gas tank is below 1/3rd full, and might get into full throttle high RPM fuel starvation at lower gas levels.

UNLESS you have a Regina FI car, those only have a tank pump, and its a different high pressure tank pump.

to me your symptoms sound like a bad ECT (Engine Coolant Temp sensor) or maybe bad wiring (82-87 volvos had 'biodegradable' wiring, the insulation starts flaking off inside hte wire bundles, then all bets are off).

if the engine revs up in neutral, but has no power in gear, your ignition timing may be fubar.

 

[QUOTE=admasters;387128]Sounds like classic fuel starvation. Check the fuel pumps and the filter. You should hear the pump whirr momentarily when you turn the key to run but not all the way to start. You might need a helper to listen.
Andrew[/QUOTE

When I turn the key I hear the fuel pump relay click, but no sound in the trunk, or under the driver side door. The fuel pump fuse is okay. I have a new air and fuel filter waiting for pickup at my auto parts dealer. Is there a way to test the pump? Should I check for voltage at the tank pump? I havnt had more than 3 gallons of gas in it since I got it so I have no idea how it feels on a full tank.

 

What do you mean by fubar??

 

Uh, uh, uh. Uhm. Frazzled Up Beyond All Repair? That means it needs to be replaced!

Definitely sounds like a fuel problem, as has been stated! I'm sure this has been linked here a lot, but this is the most comprehensive overview of 240 fuel pumps on the interwebs. If you read it, and take it in, you'll have a better understanding of fuel pumps than most people; In the Tank - 240 Volvo Tank Pump and Sender

I know you're not driving a 240, but it should be largely similar, or at least give you some more troubleshooting ideas.

 

the fuse trick is a lot harder on a 740. so is jumpering the relay, since its in the middle row under the center console, its not nearly as easy to access the contacts.