Hi, I am a noob. I have been reading this and other Miata forums for over a year now. This forum is by far the most informative and entertaining. I have not needed to post any questions because I have found the answers here or at the garage at m.net.
Our first Miata was a 02 Bose package with leather, six speed. It was my wife’s car but I loved to drive it. It was taken from us in 05, totaled by another driver.
After autoxing my stepsons 94 I had to get another. I found a 99 in October 07. It has been a fun project. I got all the info from this forum. I bought all my stuff from vendors on this forum. Every thing has been running great until now.
She starts fine, runs fine until at operating temp. Then she has a low idle 400 rpm up and down, doesn’t stall but close. If I switch on the a/c it idles at 1000, which has been normal. I am running the stock ecu, which was chipped and flashed by g.i.a.c. So I don’t have any control on the settings (mistake 2). I think I may be loosing the coil pack. I was going to order another just in case. A couple of weeks ago I read a thread on this form about a dealer who had them fairly cheep. They were from another Mazda but didn’t have the mounting bracket. I have searched for the last two days and cant find that post.
I guess I am going to have to learn how to navigate this forum better. Does any one remember the vendor who had them?
Thanks and let the bashing begin!

 

I think I paid close to $130 with shipping when I got a new coil pack. They might be able to be found for less.

Find out if they are compatible between our cars.

I am guessing a vacuum leak is the problem.

 

I am going to check everything tomorrow; I just want to have a spare coil pack just in case. I can’t afford to replace my cat if it starts or fails on a road trip.
I am going to start with the plugs, loose sensor wires, vacuum leak, and the usual stuff. It is just strange that it is sporadic, but when a/c is on it is fine. Now that I think about it, it started at an autox last week. The same time a fan motor went out and I ran hot while between runs. It didn’t overheat just hotter then usual.
Do you remember where you got your coil pack? I think 94 to 97’s are different then 99 to 00’s then I think they changed again. I guess I will do some googling if I can’t find that post.

 

I think it was Trussville Mazda.

I still have my old broken coil and my shitty clogged cat if you want them..