I have seen in several posts that the coil should test between 11-13k ohms. I tested mine and the value varied between 21 and 24k ohms. I am currently chasing a loss of quarter mile mph and was wondering if this could be the problem? Car is not missing, just lays down in third. ET's and mph are a full second off, meaning 13.1@ 97 mph with converter locked! Thanks
Coil Ohm Test
- Thread starter squeeze87
- Start date
10SECONDVSIX
MORE AIR
- Joined
- Jun 3, 2002
Anything over 11,500 ohms is a Coil starting to go...
Intercooler
New Member
- Joined
- May 24, 2001
Take the last post with a grain of salt. This is the same responder who only had a little snip against Sealed Power cams and ducked out. 11-13 is fine. If you get over 14 then be concerned. I have seen a bunch at 12.5 whick according to 10SECOND would be bad (they weren't).
And to add fuel to the fire, even a good reading of 11-13K doesn't always mean a good coil. I've got one stuffed away in my garage here (coil pack) that reads perfectly at 11.5k ohm across all three sets. Put it on a car though and the world comes apart at ANY boost levels. Replace it and life is good again.
A good coil tester or swap with a known good piece are the only sure ways to know.
A good coil tester or swap with a known good piece are the only sure ways to know.
Red Regal T
Senior Member
- Joined
- May 24, 2001
EXCELLENT INFORMATION.
- Joined
- May 28, 2001
Coil problems
Dave H. wrote:
And to add fuel to the fire, even a good reading of 11-13K doesn't always mean a good coil. I've got one stuffed away in my garage here (coil pack) that reads perfectly at 11.5k ohm across all three sets. Put it on a car though and the world comes apart at ANY boost levels. Replace it and life is good again.
A good coil tester or swap with a known good piece are the only sure ways to know.
__________________
TurboDave
MANY others, including myself, have stated we think the ohm test is INCONCLUSIVE, only to see posts to the effect, "naw, not true, ohm it and go on".
A CASPERS coil/module tester is a MAJOR piece of equipment that anyone messing w/ these cars needs. An OHM test will not show what happens when a load is placed on the system by high cyl pressures, period.
BTDT!
Nuf said..
Back to testing my coilpak!
Dave H. wrote:
And to add fuel to the fire, even a good reading of 11-13K doesn't always mean a good coil. I've got one stuffed away in my garage here (coil pack) that reads perfectly at 11.5k ohm across all three sets. Put it on a car though and the world comes apart at ANY boost levels. Replace it and life is good again.
A good coil tester or swap with a known good piece are the only sure ways to know.
__________________
TurboDave
MANY others, including myself, have stated we think the ohm test is INCONCLUSIVE, only to see posts to the effect, "naw, not true, ohm it and go on".
A CASPERS coil/module tester is a MAJOR piece of equipment that anyone messing w/ these cars needs. An OHM test will not show what happens when a load is placed on the system by high cyl pressures, period.
BTDT!
Nuf said..
Back to testing my coilpak!
Mile Hi GN
Member
- Joined
- May 23, 2001
Re: Coil problems
I could not agree with that more.
I had a totally random pop. My coil Ohm'd right on the money, Ohm'd it time and time again.
Tested the coil/module with Caspers coil/module tester and sure enough, 2 and 5 were weak and intermittent. Replaced my perfectly Ohm'd coil pack and module with a new one and problem solved.
The tester costs $109 and it's worth every penny of it.
CCCI Ignition Simulator, 86-89 Turbo Engines
I could not agree with that more.
I had a totally random pop. My coil Ohm'd right on the money, Ohm'd it time and time again.
Tested the coil/module with Caspers coil/module tester and sure enough, 2 and 5 were weak and intermittent. Replaced my perfectly Ohm'd coil pack and module with a new one and problem solved.
The tester costs $109 and it's worth every penny of it.
CCCI Ignition Simulator, 86-89 Turbo Engines
Another thing you can try is going to Autozone. They have a testing procedure for checkng the internal componets as well as the spark plug towers on your coil. They just did mine, if you are interested I can sell you that coil, the ignition module is crap, so I am left with a spare coil.
Well, I took my coil to a guy who has a Caspers coil tester and 2-5 spark got weaker and weaker then finally went out. replaced with a new coil pack and retested just to be sure and all looks good. We'll see if my top end power comes back after i put the rest of the car back together.
The Radius Kid
Active Member
- Joined
- Jan 26, 2002
One thing that is missing form any "ohm" test on a coil pack,is the resistance of the Primary side of the coil.You also need to know the resistance between the primary side and the secondary[should be infinite].On car ohm testing does not address the primary side issue,hence the wonky results people sometimes get.
Casper's tester addresses both sides of the coil at one time so you get no lies[provided the center contacts of the tester are properly in contact with the towers of the coilpack].
The best package to get from Casper's,is the tester with the plug gap extenders and test everything right to the plug boots.
I thought I had a bad coil pack[2-5 ,brand new].Hmm,let's use those gap extenders and the wires and run the full test.Perfect.
That explains the changing results I was getting when using the tester alone.
However,11.5K- 13.5K should be just fine for the secondary side,provided all the coilpacks are firing right.
Casper's tester addresses both sides of the coil at one time so you get no lies[provided the center contacts of the tester are properly in contact with the towers of the coilpack].
The best package to get from Casper's,is the tester with the plug gap extenders and test everything right to the plug boots.
I thought I had a bad coil pack[2-5 ,brand new].Hmm,let's use those gap extenders and the wires and run the full test.Perfect.
That explains the changing results I was getting when using the tester alone.
However,11.5K- 13.5K should be just fine for the secondary side,provided all the coilpacks are firing right.
