95 850 Wagon - cranks w/ no spark - replaced everything!

Dandolf · Post by **Dandolf** » 24 Jan 2012, 00:34

95 850 Wagon - 2.3 Turbo - Automatic
Cranks (turns over) but no spark (fire)
I have replaced:

Cam position sensor
Crank position sensor (RPM sensor @ flywheel)
Coil with ignition control module
Spark plugs - plug wires - cap - rotor
ECU

I checked for codes using the LED thing behind the passenger headlight (A-2 port I think) and got 1-1-1 (nothing).
I Only saw 3 ground points under the hood - 2 that go from the valve cover to the firewall and 1 near the coil on the driver-side fender - I cleaned them and made sure they were good. I have power at the ignition switch, and power to the coil. Checked for spark by disconnecting coil wire at cap and by using wire with old spark plug. I even tested for spark with the lights off in case it was faint and hard to see but I saw nothing.

What is my next step?!?!?! This is getting pretty frustrating!

Post by **rspi** » 24 Jan 2012, 12:51

How are you checking for spark?

Dandolf · Post by **Dandolf** » 24 Jan 2012, 13:30

rspi wrote:How are you checking for spark?

I have been disconnecting the coil wire at the distributor cap and putting it near a ground source and turning it over. I have also been checking by disconnecting a spark plug wire from one of the installed plugs and connecting it to an old plug (one of the old ones that I replaced) and turning it over.

Post by **rspi** » 24 Jan 2012, 13:55

That will usually show you. Did you replace the cam sensor with a new one?

Dandolf · Post by **Dandolf** » 24 Jan 2012, 14:00

Everything I replaced was new except for the ECU which I was promised was good by a reputable Volvo shop.

Dandolf · Post by **Dandolf** » 24 Jan 2012, 23:40

As far as I can tell there are no relays for the ignition system...Is that right?

Is there a component of the anti-theft system that could immobilize ignition?

boggy · Post by **boggy** » 25 Jan 2012, 16:20

If you are successful at figuring this one out let me know - I'm in the same boat as you. Mine cranks too, but no spark. I just replaced or verified that all of the same components are good on my 97 850 and I still don't get spark. To my knowledge the anti theft system can be overridden; the relays are located under the dash. I'm not sure if that will solve the problem though. The alarm system wouldn't allow the engine to turn over if it were activated, maybe I'm wrong...anyone out there have an answer?

Dandolf · Post by **Dandolf** » 26 Jan 2012, 15:05

I was told by a volvo tech that a bad cooling fan relay can cause no spark - don't know if that's true but I replaced it and it still didn't work. I think I have a bad wire somewhere...

boggy · Post by **boggy** » 26 Jan 2012, 17:23

Agreed. Most likely there's a short in the wiring.