Parts Catalog Accessories Catalog Tech Info Tech Forums
 
Follow Pelican Parts on Facebook Follow Pelican Parts on Twitter Follow Pelican Parts on Instagram Follow Pelican Parts on YouTube Follow Pelican Parts on Pinterest Follow Pelican Parts on Tumblr
  Search our site:    
View Recent Cars  |   Cart  | Project List | Order Status | Help    
 >  >
Coil Testing and Replacement
 
Bookmark and Share

Pelican Technical Article:

Coil Testing and Replacement

Steve Vernon

Time:

1 hour1 hr

Tab:

$85 to $220

Talent:

**

Tools:

10mm wrench, flathead screwdriver, multi-meter (for testing only)

Applicable Models:

BMW E10 2002 Coupe/Conv (1967-76)
BMW E21 320i Coupe (1977-83)

Parts Required:

Coil

Hot Tip:

Disconnect battery when replacing

Performance Gain:

More power

Complementary Modification:

Check spark plugs

If you are having hard start troubles or the engine is not firing properly, one of the three places you should check are fuel, air and the spark. If you are not getting a spark to the plugs (please see our article on testing for spark) you may have a bad coil.

This article will describe to you a few simple procedures for testing the coil along with instructions for replacing it if it is bad.

To test the coil make sure that you have a good battery first. Next, the coil should always have 12 volts when the ignition is in the ON position. With the ignition in the ON position place your multi- meter on the black wire on the coil and the ground. If you are not getting 12 volts then you have a problem with the ground or power to the coil. Next remove a spark plug. Disconnect the coil wire from the distributor, and ground the plug to the engine with a set of jumper cables. Do NOT touch the plug while running this test! Turn the ignition to the ON position. Jump the battery negative to the green wire on the coil. The plug should wire or spark for every time you touch the green wire. If it does not then the coil is probably bad. On our project car there was no spark so we knew we had a broken coil and needed to replace it.

The coil is located in the right rear section of the engine bay mounted to the right fender (red arrow).
Figure 1

The coil is located in the right rear section of the engine bay mounted to the right fender (red arrow).

If you have performed the tests and know that the coil is bad and are going to replace it, begin by disconnecting the ground to the battery (red arrow) and placing it so it cannot come in contact with the battery post while you are working.
Figure 2

If you have performed the tests and know that the coil is bad and are going to replace it, begin by disconnecting the ground to the battery (red arrow) and placing it so it cannot come in contact with the battery post while you are working.

Depending on whether your vehicle has an old points and condenser distributer or a modern upgrade to pointless will determine how many wires are connected to the coil.
Figure 3

Depending on whether your vehicle has an old points and condenser distributer or a modern upgrade to pointless will determine how many wires are connected to the coil. Our coil has a pointless distributer so we have pigtails added to the coil (red arrows); whatever system you have just make sure to label the wires to the corresponding poles and reinstall them in the same manner.

Carefully separate the coil to distributer cable (red arrow).
Figure 4

Carefully separate the coil to distributer cable (red arrow). Do not pull this cable off by pulling on the wire part or you can damage it. Take your time and gently remove it from the coil by the base of the wire.

The coil is a tight fit against the fender.
Figure 5

The coil is a tight fit against the fender. Since we are working on the Clarion Build's BMW 2002 show car with an absolutely beautiful new paint job, we want to make sure we do not damage the paint. The bracket has cut outs in it so you do not need to completely remove the mounting bolts but just loosen them. To remove the coil use a 10mm wrench and loosen the bolts on the mounting bracket (red arrow, one shown).

Slide the coil off the mounting bolts using care not to scratch the paint.
Figure 6

Slide the coil off the mounting bolts using care not to scratch the paint. With the coil out of the car, if your new coil did not come with a new bracket, or you want to use the original you can transfer the mounting bracket to the new coil using a flathead screwdriver. Installation is the reverse of removal.


Bookmark and Share

  Search our site:    

View Cart & CheckOut | Project List | Order Status |  Help    

 

[Home] [Customer Service] [Shopping Cart] [Privacy Statement]
 [Contact Us] [About Us] [Shipping] [Map to our Location] [Careers]

Copyright © Pelican Parts Inc.

Page last updated: Sat 12/3/2016 02:59:01 AM