I have a 2000 S80 T6 and would like some help. It started about month ago it would stall (driving or stopped) it did this about 5 times about two weeks ago the STC Service Required light came on. On Monday I went to start and it would just turn over (not hitting or anything). Here's what I done (as far as test)

Checked fuel to fuel bar (OK)
Pulled two plugs (both dry as a bone)
Tested coils with spark plug (no fire)
Checked all fuses (3 Panels)
So it seems that i'm getting fuel to the bar but the injectors are not pulsing and no fire on coils.

Crank sensor and/or cam sensor reads .122 on the ohm meter

I have notice the throttle unit (with the key on) has a high pitch whine. Could this be the problem? I have no fire and fuel to the fuel rail only. A mechanic (not volvo) friend said he thought the ECU was out. I called a local salvage yard and they have the exact one (but don't want to waste money) being one of the millions and millions of unemployed just can't take chances. I have also unhooked the battery a couple of times and notice I get a different warning message(s) each time (stc service required, Air Bag, etc). I would normally take to volvo dealer but again don't have the cash. Any help would be more than appreicated.

 

Fuel to the rail does not mean much unless it is pressurized. Check the pressure and flow.

I am fairly certain if you pick up another computer it will need software loaded to work with your car. Suggest you look into this before you spend the money.

I would concentrate on other parts before replacing the computer unless your mechanic has a specialized Volvo tester which shows the computer is bad.

I had a computer problem which turned out to be the wire attached to the computer main power relay located in the electrical box next to the ABS module under thew hood was causing intermittent connection with the relay. The connector on the end of the wire was bad. Look for signs the connector has overheated or the surrounding plastic has melted.

Try a shot of ether (hi grade starting fluid) into the air tube feeding to air to the throttle body from the intercooler. Reconnect it before cranking. If the engine kicks, you can be fairly sure you have a fuel related problem.

Don't use to much ether.

 

I tried what you said with the ether and it hit so what do you recommend for the next step.

 

Need to figure out if it is getting right amount of fuel pressure at fuel rail.
Best way to do is with a pressure guage. Attatch to the fitting at the end of the rail. Alterative is remove the fitting and verify you can get a steady stream of fuel as soon as you start cranking engine.

If no pressure at the rail, listen for pump running as soon as you turn on key. It will run for about 3 seconds each time you turn key on. If it is not running, need to measure for voltage feeding pump to determine if problem is with pump or power going to it.

If pump runs, try a new filter. Is a long shot.

Has car been run out of gas recently?

If you are getting proper fuel at rail, sounds like ejectors are not firing the fuel or right amount of it into the combustion chamber. Much more complex to trouble shoot without propper equipment.

PS- If engine fired, you must be getting spark at the plugs.

Mathews website has schematics
http://www.matthewsvolvosite.com/volvo-wiring-diagrams/

 

I have not changed the fuel filter.

Here's what i did this morning.

Fuel Pressure test

Turn key on and pressure jumps to 350kPa/54# then within 30 seconds down to 325kPa/46#. VADIS says the must be 375-395kPa

Twenty minute bleed off shows a drop to 325kPa/46# (acceptable according to VADIS must not fall below 200kPa in 20 mins.)

Will this keep the injectors from pulsing fuel? Could the filter be stopped up or would this most likely be a fuel pump issue? Remember it will hit with ether.

 

Can you check the pressure while cranking the engine? If it maintains the pressure, it is not likely your fuel filter.

Try unplugging the MAF sensor coming from the air cleaner box and try starting it. I heard when this goes, if you unplug the sensor sometimes it will start in limp mode.

Take out a couple of the spark plugs to confirm they are dry (not wet from fuel).

I do not know how to verify if an electrical pulse is getting to the fuel injector. Maybe someone else can help with this. You should have a pulse and the pulse has to be a certain duration for it to run right.

I am also not sure which sensor controls this electrical pulse. Maybe someone can help with that. There is a cam sensor and a sensor on the flywheel which is located on top of the transmision bell housing.

Does yout tachometer jump all around when you crank the engine?

Try holding the accelrator to the floor when you crank it.

Without the right tool to read the codes, you can spend a lot of time looking for a simple problem. Are there any idependent service centers in your area who specialize in Volvo's who will read your codes?