Another Cat?

Thanks to Leon, Nora, and others, my "Green Hornet" is really running great. My check engine light came on last week...again. A couple of months ago, I had Mazda install a new cat converter, under the emissions warranty. Then I found out that the ignition coil was the probable cause for the cat failing in the first place. I had a couple episodes of the ignition coil failing, causing the car to backfire and run really rough. I bought a new ignition coil from Trussville Mazda, along with 4 ngk plugs. I got some really nice

8mm Magnecor plug wires from FlyinMiata. So my question is...should I have Mazda replace the 2 month old cat? I've got 3 years and 15K miles left on the 8 year, 80K mile emissions warranty...maybe I'll just wait until the remaining time is up, before getting (another) new cat. Thanks for your help! jim
Reply to
Jim Untch
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No, you should find out why the coil failed, and fix the problem before it happens again. The usual cause--especially if the tach was acting strangely--is dirty ground connections, so begin by disassembling and cleaning them. If you have an NB, I can't tell you where they are with any confidence, but on an NA, the usual suspects are on the head next to the throttle body and on the bodywork under the master cylinders.

Reply to
Lanny Chambers

NB? That's a 99+ right? Thanks for the reply Lanny...I tried disasembling the coil pack, and cleaning the connections...that seemed to help for a week or so. Going by what I found here:

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'&t0103I'm quite confident that the 99 coil pack is a defective part. Why elsewould they issue a new part (#BP4W-18-10XB)???? I guess you guys with pre99 Miata's (NA?) don't have this problem. I got my dealer to admit thatthe Protege coil pack was replaced under warranty, but he said that theMiata coil pack is different...yeah right. later...jim

Reply to
Jim Untch

On my '92, (and this is REALLY weird), the coil pack bracket broke - there are (iirc) two bolts that hold the bracket on at the back of the valve cover (or maybe it bolts to the block, but that's not the point). The bracket snapped on one side. I have NO IDEA why - as far as I can tell, the bolts just hold it in place and shouldn't be under much stress. But it snapped. So I thought about replacing it, but that was about 80k miles ago, and it doesn't seem to cause any problems....

frinklemur

PS - Since we're talking about plug wires, I got a new set recently at AutoZone. Good news: $28, and they fixed my problems with roughness under acceleration. Bad news: They fit... in the sense that it is possible to install them. But there's 1-3" of extra wire on each one, and about 1/4" of gap between the rubber flap that's supposed to cover the hole for the plug and the actual surface of the valve cover. I don't care too much (I've firmly settled into "just keep it alive" mode[1]), but in case any of you are thinking about purchasing, stick with NGKs or Magnecors.

[1] - The Miata is getting taken out of active rotation soon. I commute ~500mi a week, and at 245k miles, what it really needs is to be put into a garage and reaaally gone through - a good cleaning, new carpet, new dash, new seats, lots of things that I've been meaning to get to. Worry not, I'll still enjoy the car now and then, but it needs a break. And in case you're wondering, I've settled on a replacement: a VW TDI Golf or Jetta in the '99 - '03 range. Anyone in the VA/NC/SC/GA area got one they're interested in sending to a good home?
Reply to
FrinkLemur

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