Mazda MX-5 Miata NB FAQ

Last update: 20 April, 2010

General Information

I'm having trouble filling the fuel tank completely

Check the back flow preventer, located in the metal part of the fill tube. It has a tendancy to stick closed.

How can I get rid of those ugly airbag warning stickers on the sun visors?

You have a couple of options here. You can buy some vinyl "Contact" paper and cut a piece to fit over the sticker. Then peel off the back, slap it on, and you're done. Cheap, but could peel off in the heat. Vinyl paint might work - though we haven't tried that. The slickest option is to track down a pair of sunvisors from an M1. New or used, you have a choice of two types: folding and fixed. Pick 'em up from a dealer or a salvage yard. Also available from at least one aftermarket vendor - a visor "sock" which gets pulled over the visor. In addition to hiding the sticker, you can use it to hold your turnpike ticket, road map, and a few other odds and ends.

Bill Hirst sent in another suggestion:

Remove the sunvisors to your workbench. Using laquer thinner and a clean cotton rag rub the sticker forcefully. After about 1 minute the sticker will start to disolve and comes off in small pieces. Fortunately the thinner does not affect the sunvisor itself....and presto great looking sunvisors without those ugly yellow stickers.

Bart Yount adds:

After using the lacquer thinner to remove the sticker you might find that the plastic material has become stretched and distorted. To remedy this problem, get a hair dryer and turn it on to hot and heat the plastic. Voile, the plastic will return to it's original shape. To make it look perfect, take black liquid shoe polish and apply to the plastic surface. You now have a nice clean, shinny stickerless sunvisor!

David Reagan suggests:

Go to any craft store and ask for a sheet of black adhesive felt. Cut two rectangles slightly larger than the signs on the visors, peel off the backing paper and stick the patches on the visors. The patches blend so well that a person would never notice them unless they were pointed out.

The soft boot keeps coming apart at the seams.

The first soft boots were crap construction. Mazda has since redesigned them. The seams which are located directly over the soft-top latches when the top is down were simply glued and not stitched. The new ones are stitched. Most of them split with a month or two of use. If you're still under warranty, take it back and get a replacement. If not, take the boot to a shoe repair and have them throw a stitch on each seam to hold it. Or do it yourself.

I have the Bose option and the doors are buzzing. What can I do?

We haven't found a solution to this yet, though we don't think it's due to the Bose system itself. More likely it's due to the door construction, and the higher power of the Bose option induces the buzzing. Complain to the dealer. Hopefully they'll come up with a fix. This letter is from a BOSE OEM Service engineer:

Some customers have recently indicated to us that they are experiencing a variety of symptoms similiar to which you describe. Mazda has informed us that they are aware of this symptom.

Let me explain what the potential problem is, why it occurs, and what we are doing about it. Some of the 8" door mounted speakers, when half wet (I'll define this in a minute), exhibit what we call a rub. In some cases this may sound like a rasby buzz, or in other cases like wood file being used. This happens, as I said when the speaker is "half wet". What this means, is when some water has made it's way into the door and gotten a portion (but not all) of the speaker parts wet. This partially wet state can cause the inner structures of the speaker to rub against each other. Although this is not a good sound, it will not damage your speaker, and as soon as the speaker dries out again, the problem will go away. This is not a situation that will get worse over time. This symptom will come and go with the speaker's exposure to water. Simply, if you can relate the problem to water exposure, and the symptom comes and goes, then your speaker would fit into this "Half Wet" category. Bose is working with Mazda to evaluate a fix for this problem.

We should also mention that, over time the door trim pieces can loosen, as most automotive trim pieces do. Due to the high acoustic energy in the door, if these trim pieces do loosen they are susceptible to buzzing.

So, if your problem is not related to water exposure, and gets worse over time, or is a constant state, I would suggest that the problem may be related to the door trim.

Curt Stuart, after going a few rounds with his dealer, decided to spring for nine bucks and bought a Waterproof Foam Baffle from Crutchfield. Curt reports that the "sound, specifically the bass, seems to be tighter and less "wild" without losing the any of the oomph of the system." Crutchfield part number 237XT80 for $9.00.

Starting the M2 seems to take an excessively long time.

If it really takes more than a few seconds, there could be a problem with the Fuel Pressure Regulator. Take it to the dealer. They should have a new fuel pressure gauge set Mazda sent to the dealers' for this system (and the new '99 Protege) and the diagram for the new single line fuel system.

I have an annoying rattle on the left side, just behind my head

Check the connector for the rear window defogger. It may be resting against sheet metal. Try wrapping it in a bit of foam rubber.

Why can't I move the passenger's seat all the way back?

There is a stop located at the rear of the seat rail nearest the center of the car, that was installed to make room for the computer being located behind the seat in '94. For some reason, Mazda hasn't removed the stop, even though the computer is now up by the driver's knees. One 14mm nut holds the stop in place. Pull the nut, remove the stop and gain two inches of leg room.

Warning: we received a message from someone who says he inadvertantly moved the seat back too far and it came off the tracks causing it to be permanently stuck. We haven't attempted to verify this, but we recommend caution in any event.

Edward A. Kleinhample writes:

I was able to simply rotate this block 180 degrees and secure it in place with the existing bolt. This gave me approximately 1.75" additional rearward seat travel (enough to get my knees out of the glovebox.

With the block in this position, the seat does hit the block before it reaches the end of the support rail.

Can the fake oil pressure gauge be retrofitted with a real, working gauge?

Yes, but it isn't quite as easy as the '94 - '97 retrofit. See the full writeup in the Garage section.

The Cruise Control Craps out

Many '99 owners have had trouble with their cruise control. Basically, after setting the speed, the car refuses to hold the setting, sometimes accelerating as much as 15mph over the set speed. You will need a replacement cruise control processor. See your dealer for the warranty work.

My wheel caps are turning yellow

This is very common on many cars. It is easily removed with an acid based wheel cleaner. We have been told that Vesco Wheel Brite works well, however it is a commercial product and not available to the general public. If you find a brand of acid based wheel cleaner that works, please let us know and we'll update this FAQ.

My rear window fell out!

We've received a few reports of this. Our understanding is that Mazda is working on a redesign to address the problem which, evidently, is quite limited in scope. We have no other details.

How long should the OEM tires on the '99 last?

We're not sure, but we can tell you that Toyo, one of the OEM suppliers for the '99, provides warranty assistance as well as consumer concessions for road hazard damage as well as a generous 40,000 mile mileage consideration. They are interested in hearing about your experience with their tires.

For assistance with 1999 Miata Original Equipment Toyo Proxes R22 tires, contact Toyo Consumer Relations at 800-442-8696 Monday-Friday, 8:00am - 4:45pm Pacific Time, or email toyotech@toyo.com

What's up with the '99 exhaust? Things don't fit.

Mazda changed the exhaust on the M2 from a separate catalytic converter and resonator to a single piece unit which contains both. The result is that aftermarket exhausts won't bolt right on. In addition, they also made a production change.   Automatics - VIN #119466 and later are affected. Manual Trans - VIN #123572 and later are affected. By "affected", we mean an aftermarket replacement muffler will not bolt directly onto the pipe without modification to the flange holes.

Tell me about the #4 thrust bearing

Randy Stocker put together a page dedicated to the subject. Also see the Miata Forum FAQ.

My glove box sags

My feet are too hot!

Tell me about the 2001 Clutch Shudder.

How do I tell if my NB came with a LSD?

For 99-02 the quick method is to check the Model # against these lists (US). Your cars model # can be found on the Vehicle Information tag in the passenger door jam (lower left corner of tag).

Mazda stopped installing this tag mid-year 02. Most if not all 02 SEs do not have the tag.

For 02+ cars without the ID tag, see the answer to the next question.

I'm looking at buying an NB and it doesn't have or I don't have access to the Model #. How can I know if it has a LSD?

For 1999 (Torsen II):
If the car came with cruise control, power antenna, windblocker and power door locks and/or tan leather interior/top, it has the LSD.
It it is a 10th Anniversary Edition (10AE), it has a LSD.
If it is a Sports Package, it has a LSD (see How to ID a 1999 Sports Package below)

For 2000 (Torsen II):
If the car is an SE or has tan leather/top and Bose Stereo (Miata LS), it has a LSD.
If the car has factory 15" wheels and the (99-00) STB in the engine compartment, but doesn't have power door locks and cruise control it has a LSD
For cloth interior cars with 14" wheels, if you can't get the Model #, then you will need to have the VIN # and phone Mazda Customer Service, asking them nicely to check what options were on the car as delivered.

For 01-02(Torsen II):
If it is an SE or has a tan leather interior/top and Bose Stereo (Miata LS), it has the LSD.
If it has a cloth interior with 5sp, factory 16" wheels and has the factory STB (see pic) but doesn't have power door locks, cruise control and remote keyless entry, then it has the Suspension Package option (see 01-02 HARD S) which included a LSD.

01-02 Miata (cloth interior, 15" wheels) could get a LSD as optional equipment. There is no way to visually tell if it has a LSD. But if it doesn't have power door locks, cruise control and remote keyless entry it can not have the LSD. Mazda required that the Convenience Package be ordered at the same time as the LSD. If the car has the Convenience package (possible LSD) and you can't get the Model #, then you will need to have the VIN # and phone Mazda Customer Service, asking them nicely, to check what options were on the car as delivered.

For 03 (Tochigi Fuji):
If the car is an LS or SE (leather, Bose Stereo, Silver interior trim) it has a LSD.
If it's a Shinsen Version (Titanium Gray Metallic paint, dark blue cloth top and blue cloth seats)it has a LSD.
A LSD was available for the black cloth interior models. They could have a LSD if the car was ordered with the Suspension Package option (see 01-02 HARD S) but a LSD could also be ordered separately.

Best bet is to get the VIN and call Mazda Customer service.

For 04-05: (Tochigi Fuji):
If the car is an LS (leather interior, Bose Stereo, Silver interior trim) it has a LSD.
A LSD was available for the black cloth interior models only if it was ordered with the Suspension Package option. Unlike the previous years it could not be ordered separately. Unless you can see the car up close and know exactly what to look for, it's very had to tell if an 04-05 was order with the Suspension Package. Again, best bet is to get the VIN and call Mazda Customer service.