I bought this 850 volvo with a no start problem, I have replace the crank sensor and cam sensor as well as the ecm with a used one same thing . I have spark but when I put a noid light on the injectors all I get is one quick flash that is brite then a few very dim ones that bairly light my noid light , any ideas would be appreciated , I have checked for the reference voltage at the cam sensor 10 volts at one and 4.75 at the other checked the crank sensor also its good checked for codes with otc scanner nothing

 

What was the original problem with the car on why they sold it?
Was it just that it would not start one day?

Also check the wiring at the relay on top of the cooling fan a gray 4 wire relay.

 

I checked the relay it has power coming to it and it closes as I removed the cover exposing the inside you can see the contacts and when you plug it in with the ignition on they close , the original problem was it would not start , it gets fuel too the rail as well 32 pounds pressure

 

I hate no-start & stalling troubles.

See attached FYR. Also check ETC (Engine Coolant Temp) sensor.


JPN

 

+1, No starts can be a tough thing to track down once you replaced all the logical things. Could even be just a bad ECU.

 

i leaning toward a bad ecu....