I have taken the car to the dealer twice now after misfiring and stalling problems. Both times the problem was diagnosed as a defective coil. When the coil was replaced the car is ok. Now it has happened again and I am suspecting another coil problem.
1.) Is it difficult to check the coils and how would I know a bad one (cracked ?)
2.) Is there some design defect with the coils or other componants? This seems like an unlikley coincidence.
Thanks,
Bluewindspeed

 

I always like to replace all the coils when one goes bad.They crack from the heat.It may be crack but still working good.
They are pretty easy to get to.Remove the black cover and then the 10mm bolt holding the coil.

Do you have a scanner to read codes?

 

Yes I have a code reader but this time no check engine light showed. Previously, the code read "misfire" according to the dealer. Is this coil failure a known problem with this car (1999)? Could a defective ECU for example be causing the coils to fail prematurly/
Thanks for you help.

 

It is a pretty common problem with the cars 1999 and newer.

Does your code reader tell you which cylinder it is?

 

I am experiencing a mis-fire at 1500rpm and when i am sitting at 90mph/140kmph it is a 99 2.4 petrol. Are these coils expencive? Is it preferable to replace all of them at the same time?
Thank you
Dan

 

Yes they are pretty expensive and yes I would replace all at the same time.

 

Thank you for that Tech!
Dan

 

Glad I can help.

 

................aren't there two 10mm bolts holding the coil??????????

 

Some have 2 screws holding each coil and others have only one screw holding it.

 

OK...............mine has two (c70).

 

The C70 and the 960 early models are the main ones that had 2 screws.

 

...............thought I removed two when I changed plugs.................but then again...........the mind is a terrible thing to lose!

 

Yup same here!!!!!!!!!!!