# Ignition coil HELP **URL:** \ **Category:** Maintenance/Repairs\ **Created:** [March 31, 2008, 9:44pm UTC](https://community.cartalk.com/t/ignition-coil-help/12426 "2008-03-31T21:44:00Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![E30bmw](https://avatars.discourse-cdn.com/v4/letter/e/9de053/32.png) [@E30bmw](https://community.cartalk.com/u/E30bmw)\ **Post date:** [March 31, 2008, 9:44pm UTC](https://community.cartalk.com/t/ignition-coil-help/12426/1 "2008-03-31T21:44:00Z")
what are the symthoms of a faulty ignition coil ? mine has power to it but not enogh to going to the distributer HELP ---
**Author:** ![the\_same\_mountainbike](https://avatars.discourse-cdn.com/v4/letter/t/c89c15/32.png) [@the\_same\_mountainbike](https://community.cartalk.com/u/the_same_mountainbike)\ **Post date:** [March 31, 2008, 10:47pm UTC](https://community.cartalk.com/t/ignition-coil-help/12426/2 "2008-03-31T22:47:32Z")
A faulty ignition coil can produce no output, produce erratic output, produce too low an output, or malfunction in wet weather due to a moisture leak. A coil’s windings are insulated with a varnish-like conformal coating. The coating doesn’t expand and contract from heating and cooling at exactly the same rate as the underlying copper wire, doesn’t have as much elasticity as the insulation on your house wires, and over time it can develop fractures. The fractures allow shorting. The shorting can be always or under verye specific conditions. The shorting can be between specific windings, which means that you don’t have all the windings working together thus producing low voltage out, or even between windings and ground (often with the sddition of moisture), which can incapacitate the coil. If you have sufficient voltage on the primary and low output (which should be measured on a scope or analyzer, because it’ll be a series of spikes with very rapid rise times and a sort of fast downward sloping, erratic looking fall. Are you sure it’s the coil at fault? What are your symptoms? ---
**Author:** ![mmsamma](https://avatars.discourse-cdn.com/v4/letter/m/ed655f/32.png) [@mmsamma](https://community.cartalk.com/u/mmsamma)\ **Post date:** [March 31, 2008, 10:55pm UTC](https://community.cartalk.com/t/ignition-coil-help/12426/3 "2008-03-31T22:55:17Z")
ohm out the coil wire,what vehicle are we working with? eng?? trans??? WHAT? ---
**Author:** ![E30bmw](https://avatars.discourse-cdn.com/v4/letter/e/9de053/32.png) [@E30bmw](https://community.cartalk.com/u/E30bmw)\ **Post date:** [March 31, 2008, 11:25pm UTC](https://community.cartalk.com/t/ignition-coil-help/12426/4 "2008-03-31T23:25:55Z")
86 bmw 325 it used to crank fire an die imideitly now it just cranks its getting curent to the ignition coil an isnt putting out enough to the distributer ---
**Author:** ![Tree\_Hugger](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/tree_hugger/32/53_2.png) [@Tree\_Hugger](https://community.cartalk.com/u/Tree_Hugger)\ **Post date:** [April 1, 2008, 1:23am UTC](https://community.cartalk.com/t/ignition-coil-help/12426/5 "2008-04-01T01:23:10Z")
Then replace the coil… ---
**Author:** ![ok4450](https://avatars.discourse-cdn.com/v4/letter/o/e9bcb4/32.png) [@ok4450](https://community.cartalk.com/u/ok4450)\ **Post date:** [April 1, 2008, 2:58am UTC](https://community.cartalk.com/t/ignition-coil-help/12426/6 "2008-04-01T02:58:02Z")
you’re going to have to purchase a manual and use a vom in tracing the fault out. lack of spark means a bad coil, bad distributor, bad ignition module, etc. did you ever verify that the coil is receiving power in both the RUN and START positions to weed out an ign. switch problem or are you testing for power only with the key in the RUN position? as a matter of fact, have you even verified that the dist. is even rotating when the engine is being cranked over? ---
**Author:** ![E30bmw](https://avatars.discourse-cdn.com/v4/letter/e/9de053/32.png) [@E30bmw](https://community.cartalk.com/u/E30bmw)\ **Post date:** [April 1, 2008, 6:14pm UTC](https://community.cartalk.com/t/ignition-coil-help/12426/7 "2008-04-01T18:14:30Z")
Yes THE COIL IS GETTING SPARK IN THE START AN RUNNING POSITION HOW WOULD I GO ABOUT CHECKING THE DISTRIBUTER FOR MOVEMENT? WOULD IT B A GOOD IDEA TO TAKE AN IGNITOIN COIL OUT OF ANOTHER VEHICLE AN SEE IF IT MAKES A DIFRENCE? HELP ---
**Author:** ![mmsamma](https://avatars.discourse-cdn.com/v4/letter/m/ed655f/32.png) [@mmsamma](https://community.cartalk.com/u/mmsamma)\ **Post date:** [April 1, 2008, 10:54pm UTC](https://community.cartalk.com/t/ignition-coil-help/12426/8 "2008-04-01T22:54:47Z")
pop the top and watch,rotor.