After the success of the articles on the EGR valve and the Spark plugs, I decided to write an article on the ignition coil, which often infrequently can cause problems.

Problems occur in a way similar to those of candles:

  • Accidental (but low) Acceleration
  • Scratches to a minimum or a low speed
  • “Exhaust gas” warning light that goes on during the march and disappears after a while.

Since the symptoms are very similar, you have to think about candles immediately (spending much lower than repairing or replacing the spark plug) and then, if it does not resolve or reappear after a few months, deal with the problem of the coil.

Hereinafter, I describe the steps for the GM Family 0 of Generation 3 (the pictures are related to the A14XER engine) and must be done with a cold engine:

  1. Proceed to remove the engine covers to freely access the lock, as if you are going to change the spark plugs.
  2. The coil is a single block and pairs with the candles directly as shown in the following picture.

Note: If the motor is connected to the spark plugs with wires and pipettes, check that there are no problems with the wires (cuts, dots or tie). If the cables do not have trouble disassembling the coil and check the connections first (eventually spin some antioxidants on the connectors) and eventually replace the coil itself.

Engine without cover

  1. Unscrew the screws that hold the stand in place. In this case you must use the Torx keys.
  2. Disconnect the connector that you find a desrta. Caution: The connector may be difficult to remove but never force it by pulling the strings. To “unlock” it, first slide the stop (red or yellow) outward and then press the tab to disince it. The tongue is very durable if used correctly but at the same time it is fragile if the force is incorrect.
  3. Once the connector is removed, the entire mouth of both sides can be lifted upwards to lift it horizontally.


Here’s what you have in your hand the reel to be controlled for good:

Are there any cracks in the seals and so it has penetrated into moisture? (If you check the oxidation of the contacts, in any case you would see it from the candle. Use the antioxidant after digging out the oxidation and changing the pieces (for the reel in the picture the pieces found in the code GM 95514599)

Does the coil no longer have its duty? You can check (but you must be expert) shown in this video on YouTube

If you discover that the coil is damaged you can replace it with a brand-new one.


WARNING: carefully verify the code of the ignition coil you need for the engine you have. Also check the number of the pins (there are 6 and 7 pin layout)