Good job on all of the parts that you replaced.
Did you replace the big fuel filter beside the external fuel pump, under the car? If could be blocked up.
Unplug the AMM or maf and drive it. If it drives like crap but drives better, the AMM is probably faulty.
A dirty t-plate will cause the engine to start/idle poorly. The engine can not get enough air at idle and knocks off.

 

So I unplugged the maf and tried starting it and it will fire a few times but it won't stay running.
I then plugged it back in and I would crank it for ever just to get it to sputter.
I eventually got it started and tried unplugging it while running, it just killed it so maybe the fuel pump is bad. I didn't replace it so maybe it's the problem?
the lady I bought it from told me it needed a in tank fuel pump, I pulled the pump and tested it and it didn't work but maybe that wasn't the main issue?
If I could test the fuel pressure I would but I cant find the Schrader valve on the fuel rail, u don't think this rail has one.
Also, I don't know what a t plate is, can you please explain?
Thank-you for the useful info!

 

t-plate is the throttle plate. Hot oil pcv vapor gets burnt by passing through the throttle plate into the engine. Hot oil vapors will build up and coat the colder throttle plate. Over time the buildup will restrict air flow at idle. There is not a Schrader valve to test the fuel pressure. You remove the inlet hose going into the fuel rail. Connect a Volvo fuel gauge in line to test fuel pressure. The main pump under the car could be failing. If replacing the main fuel pump, use only Volvo or Bosch brand. I have seen some non-Volvo brand fuel pumps work at idle. Pressing the gas pedal, fuel pressure would drop from 40 psi down to 10 psi and engine shut off. Check all of the fuses below the hood pull handle. Volvo used ceramic aluminum fuses. The aluminum will dry out, crack on the edges and/or center section of the fuse. The fuse does not blow, the crack causes a serious voltage drop. Clean any corrosion where the fuse edge makes contact with the contact ends. If aluminum fuses, replace all with copper type fuse.
On your car, inspect the 25amp fuse, holder, wire ends and small red wire at positive battery post for burnt terminal ends and corrosion. Located just behind the battery area. This is a common issue with age and wear. This will cause a serious voltage drop to the engine running system and fuel pump.
Below is fuses from ipdusa.com
8 amp in pic is aluminum. 16 amp is copper center. 30 pc kit is all copper center.
local AutoParts may have these fuses also.
Plastic hose fuel line coupler between fuel pump and fuel filter can crack during remove/install.
ipdusa sells them if needed.
Make sure that the ignition cap/rotor is Volvo or Bosch, Kock off ones can run like crap.
Crank speed sensor output wire can fail over time due to engine shake. It is located below the back of the head mounted to the top of the engine block. Crank sensor reads the flywheel revolutions. This tells the ignition brain that the engine has RPM's, make spark and tells the ECM to turn on the fuel pumps.
Normally the engine will crank and no start. It is harder to do on a 240. Reach down in behind the head.
Grab the crank speed wire push, pull move sideways while someone cranks the engine over if it starts and runs better, replace the crank sensor. Or plan on replacing the crank sensor eventually. It is not easy removing/installing the 10mm head bolt holding the sensor in place.
Prancing moose page has lots of 240/740 Volvo info/stuff, great site.

Prancingmoose.com, Dave's Volvo Page
C:\Users\dbart\AppData\Local\Temp\mso80BF.tmp
The Volvo Parts, Accessories and Performance Specialists Since 1963
30 Piece Fuse Kit for 240 & 260 (Thermal Plastic) for Volvo - Flosser

 

Sorry I still don't understand, is the throttle plate in the throttle body? And would I have to take the intake manifold off to clean it?

 

So I've come to the conclusion that either the maf or the iac is bad because I was dismounting the throttle body and after taking the air intake line off I decided to test the fuel pump so I don't waste time chasing the wrong problem, I turned the key and hard the main

 

Sorry, clicked the post button on accident.

Anyway, I turned the key and heard the main fuel pump kick on, I decided to crank the engine over while I had the maf/iac disconnected.



The car started after about 3 seconds of cranking, it sounded rough but it had great throttle response and didn't want to stall.



I put the iac back on and this other line that goes to the block, it ran I little worse but still had some throttle response and it didnt die.



Does anyone know what this line does that's in the pictures below?
(The line with the red dots is the one I'm talking about)

 

Also I plugged in the maf sensor and tried starting it and it started up and ran for a couple seconds and died.

 

Blue circle long hose is fuel return to the tank from the fuel pressure regulator.
Yellow circle nut is fuel pressure in from the fuel pump to fuel injector rail.
Green circle is pcv trap, hot oil vapors are directed from the engine block into the
fresh air intake hose in the inlet side of the T-plate or throttle butterfly valve.
White circle line could be engine vacuum going inside the car to 3 push buttons.
3 push buttons for dash vents are vacuum controlled.
You may have a serious vacuum leak. Check pcv hose 6 is connected.

pcv system.

 

Sorry, I should of clarified.

The white circled line goes to the intake manifold and appears to not be leaking.

Also today I had to move the car so I took the intake hose off the maf and took it down the block, it ran great and kept a good solid pace at about 1/4 throttle, I would push it to about 1/3 throttle and the rpms would start to rise and fall.

It did preform great at 20 mph but it would idle really low, the thing would stay running though.

I still believe it to be a maf sensor issue but the pcv line had tape on it as if it used to be leaking. this same purple tape has been found on other lines that were leaking so it wouldn't surprise me if it was a combination
of the maf being bad and a vacuum leak.

I'll check the line tomorrow and update you on what I find.