Volvo 850 turbo won't start - bad coil?
 

I've got a '94 Volvo 850 turbo. It has a electrical drain I haven't tracked down so if I leave the car sitting for about 3 days the battery will be dead. Usually I just jump it and it works fine. It's a pain in the ass but not a big deal.

Recently, I let it sit for 4 days or so and the battery died. I hook the battery charger up and try to jump it. It just cranks and cranks now and doesn't fire at all.

I checked for spark and I wasn't getting any. I tracked it down to the coil not giving any spark. I was going to try to start it with just an aftermarket coil I have sitting around but the wiring is all screwy.

There are 2 wires going into the coil. BOTH are positive and neither has a charge when the ignition is turned off. So, I figure it's just grounded to the frame.

The question is what do the 2 different wires that are both positive do? I want to hook up a coil that has just one positive and one negative post. Should I just ground it to the frame?

Re: Volvo 850 turbo won't start - bad coil?
 

Is your coilpack a combination of igniter and coil? Do you know for sure that both wires are supposed to be positive? You might have a short to battery positive on the coil ground, which is very possible on an igniter circuit.

Re: Volvo 850 turbo won't start - bad coil?
 

Not sure about the drain as I thought I had one but it just turned out to be the battery. Also check out the glove box light as that is one thing that causes parasitic drains on these 850's. Check this out for installing the coil.
http://www.ipdusa.com/uploads/sku_files/12552_INST.PDF

Re: Volvo 850 turbo won't start - bad coil?
 

I just made sure the glove box light stays off... update later on if that fixed it. Thanks a ton for the link to the PDF... I'll take a go at getting something wired up and tested tomorrow.

Re: Volvo 850 turbo won't start - bad coil?
 

Bump this up, my car is still broken and it's raining now so I can't take the bike.


* I'm really not sure if it's a combo igniter and coil, I'm not super good with ignition systems.

Recap: Was running, battery died (fixed that problem, it was the glove box light) and when I tried to start it again it just cranks and cranks. I have 2 12v positives going into my coil (definitely a possible issue) and no spark coming out.

What the hell should I test next? I tried hooking up another coil I had just sitting around but that one didn't spark either. I'm not sure if it's because they weren't compatible or because something else is fucked.

Re: Volvo 850 turbo won't start - bad coil?
 

did you leave your key on or have a bad ign switch/tumber that triggered the ign on? good way to fry a coil

Re: Volvo 850 turbo won't start - bad coil?
 

no... it was the glove box light. Aren't coils generally interchangeable though? Put a good one in it's place, hook up the wires, test?

Re: Volvo 850 turbo won't start - bad coil?
 

..yes and no. primary and secondary resistance plays a part. primary resistance keeps ign pickups/points from getting cooked, secondary i'm not sure on. something to do with burning plug electrodes i think? im drunk i dont know

Re: Volvo 850 turbo won't start - bad coil?
 

If I replaced it with an OEM one though it should work then?

Re: Volvo 850 turbo won't start - bad coil?
 

i dunno. whats the resistance on your coil?

ground to spark out, then 12v to trigger.