I have a 1998 Volvo S90. I needed to replace the spark plugs recently, and it has become quite an ordeal. I'd like to test the coils, but I don't have a tester that can do it. Is there some way that I can tell if all of the coils are the same voltage? Thanks for any input you might have.

 

im pretty sure you can do it with a multimeter. i think you measure their resistance. if i recall correctly

 

About all you can hope to do is check the primary coils for continuity - if you have an ohm-meter connect the red and black leads to the two pins inside the connector housing at the top of the ignitor unit. Checking the High Voltage levels while operating is 1)dangerous and 2)not really necessary.

If you feel like the car is missing - while it's running, starting with #1 unplug the connector from the connector housing. If the engine begins running more roughly - plug it back up - that coil is good! If you've got a bad coil, when you unplug that one - things WON'T get any worse since the coil is defective anyway. That's the best approach I can give you!

good luck.

 

I know the 454 well, popular little bike. Don't know how to use the multimeter, but there is a very good, simple coil test you can do in minutes, assuming your CDI pulse units are ok: 1) disconnect both spark plug wires from the spark plugs. 2) unscrew either one of the spark plugs and stick it back into one of the wire caps. 3) Lay the plug down on the cylinder head or anything grounded. 4) with key on, run your starter for two seconds and look at the end of the plug: a nice, fat blue spark = healthy coil. A weak, sick-looking orange spark = dying coil. Hope this helps
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Testing coil is very easy compares to checking three leads components such as SCR, FET and etc. In general, a coil consists of many turns or wire wrapped around a common core. The core could be made of iron or even air. When an electric current passes through the coil, a magnetic field is produced. A coil in some respect s acts just opposite a capacitor. A capacitor blocks DC while allowing AC to flow through it; a coil allows DC to flow through it while restricting AC current flow. Another name for a coil is an inductor.
Coil or inductor can be test using an analog, inductance or a coil meter such as the dick smith flyback tester. A coil that is small in size, I would usually just test it with analog meter and you could check it on board too. Set your analog meter to X1 ohm and place the probes across the small coil. The meter should show some reading (or continuity) and this proved that the coil winding is okay. Small coils seldom spoilt because it have less winding compares to big coils where it could have many turns of winding and chances for it to go shorted is very high.
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Hi, I have a volvo xc70 late 1999, It started losing power while driving then picked up again. I made it to a gas station fine but when I pulled in my car stalled. I put gas in and waited a few minutes, it started fine. Next day it drove fine I even drove in a rain storm. Next day I pulled out of my drive way went a short slow distance pulled a U-turn and it stalled. ( It felt like it was running out of gas, but it had gas) I pushed it out of the street and waited 5 minutes and it started. Next day tried to make it to the store, it stalled at a stop sign then started right back up then stalled 30 seconds later and I drifted to a parking spot. I tried to start it but it wouldnt turn over just a click and everything was dimming and losing power. I thought it was either the battery or the altenator. I had AAA come out and test the battery it read fine the battery just needed a charge. Car still wont start but will turn over of course now but heres where it gets wierd.. theres a heavy fuel smell inside the car from trying to start it. I'm thinking it must have something to do with the spark plugs or coils or something is shorting and not igniting so it smells like fuel. Just replaced the ETM from Exmodex and put in a fuel filter today. We checked everything did noticed some liquid by the sparkplug coils I think thats what they're called. If anyone could help me with a little knowledge that would be great. 3 kids 1 broken car and xmas is around the corner... what a nightmare.

 

Why do you want to test the coils? Is the car missing?

 

I hear ya man!!! Wife just totalled the 850 turbo with a deer, and the S70 is not firing on one of the cylinders....ARGH!!

 

hi there, just wondering if you ever figure out the exact problem of your car stalling and losing power while driving. mine did today twice, for the first time ever and im in a frantic. lights on the dash blinked and then power gone. please any info or suggestion would be appreciate. i cant afford to get volvo dealership to diagnoss it for 300bucks. thank you for your time.

 

You may want to post a new thread or post in a thread that talks about stalling. My experiance with Volvos stalling were with the battery being dead/bad and fuel pumps & fuel relays.