coil pack testing question
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On The Tree
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coil pack testing question Need help on testing coil packs to find out if they are good or bad. How do you test the spark plug wires for resistance with a volt meter? They are MSD 8.5mm, the car is running rich and it has misfire when idealing, but the car has no missfire at 1000rpm's. Please help me find out what it is. Thanks 
TECH Senior Member
Joined: Nov 2001
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From: Lake Zurich, IL
for wires, I just use a standard ohm-meter... if the value is really high (compared to rest) then I replace the wire
for coil packs... only way i've tested them is if I get a code for any issues on a specific cylinder... I swap that coil pack with another... if the code follows the coil pack then it's the pack
for coil packs... only way i've tested them is if I get a code for any issues on a specific cylinder... I swap that coil pack with another... if the code follows the coil pack then it's the pack
On the tree
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I know when I tested my motorcycle coils which are coil on plug similar to the LS1 you take the volt meter and put it on Ohm mode. Take the positive lead of the tester and put it on the lead where the sparkplug attaches to the coil then put the ground lead on one of the terminals in the harness connector on th coil and it will give you the reading for the one of the coil circuits.
There are two, one primary and one secondary. Once you do the above switch the ground over to the opposite terminal on the harness plug and it will give you the other reading.
Thats how I did, but you need to know what the factory Ohm specs are for the primary and secondary circuits in order to be able to tell if they are out of spec.
There are two, one primary and one secondary. Once you do the above switch the ground over to the opposite terminal on the harness plug and it will give you the other reading.
Thats how I did, but you need to know what the factory Ohm specs are for the primary and secondary circuits in order to be able to tell if they are out of spec.
