Hi all, I have a 91 240 that has been sitting over a year awaiting time and funds to do some much needed maintenance as well as replace frozen calipers and broken rotors. I'm getting fuel, it appears I'm not getting spark. According to my Haynes 240 manual and my Chiltons Volvo manual I may have a bad coil with slightly higher resistance (11ohms), and when I measure voltage on the white/red tach wires while attempting to start I see no voltage. I believe I read in this forum that I should see voltage when the C.P.S. sees the timing spot on the flex plate on these white/red wires on my coil. I have 3 wires on my cps, the outer insulation is mostly gone as well as the Mylar shielding. What would be the best way to determine what the cause of my no spark? I have new plugs, wires, cap and rotor just installed(O.E.M)

 

the CPS goes to the ICU, and that in turn sends the pulses to the power module which fires the coil.

the ICU also sends the timing pulses to the ECU which uses them to time the fuel injection, so if you're getting actual fuel injected when cranking, then your CPS and ICU are functioning.

the power module input from the ICU is a grey shielded wire on power module pin 5 (shield connected to power module pin 3). when you're cranking, you should see a weak AC signal on this. the power module OUTPUT is the red-white wire from pin 1 of the PM to pin 1 of the coil, and to the tachometer.

so, if you see signal at power module pin 5 while cranking, and nothing on pin 1, then I suspect your PM is bad. oh, it gets power on the blue wire to pin 4 and ground is the black wire to pin 2.

 

OK, I should have mentioned I also replaced P.M., it is not a Bosch, stepson picked it up at one of the big chain stores. I'll check it out tonight. Thanks!