Mazda Repair: mazda miata dead cylinder, miata mx, mazda miata

Question
i have a miata mx-5 i believe its 05 model ive got one cylinder not working so there is a miss but its getting fire and plugs have been gapped and changed still missfires idling or moving what could it be?

Answer
The most common cause of your problem in 01-05 models is an ignition coil or delivery of ignition energy.  You have two coils that fire 1/4 and 2/3 respectively.  Check to see that you have fire on two and fire on four by pulling the ignition wires on each one at a time and using  test plug tool to ensure you have sufficient ground.  Look for the spark.

If no spark on one then you've isolated to that coil or wire being the issue.  If you want to double check yourself swap the front coil and the back coil with each other (they are the same) and see if the fault follows the coil.  If you have spark on both the next step would be to pull the coils and inspect the plastic boots especially where they are covered in rubber, check for cracks and to pull the boot from the coil and inspect the spring winding inside the connection for a break or burning.

I'm confident you'll discover the fault if you follow these tests.  Internal mechanical failures are rare.



service@miatashop.com




"if your good at what you do, you should be well paid for it"