Last updated: 16 December, 2011
Back in the day, new engines had special "break-in" oil which was necessary to help get everything seated properly, get little bits of metal out of there, and essentially make up for the fact that engine's weren't exactly blueprinted. Automotive engine design as well as lubricant technology has evolved dramatically in the past 20 years. Manufacturers no longer use break-in oil. Engines are designed on state-of-the-art CAD systems, and manufacturing methods have improved to the point where tolerances are extremely tight. Engine break-in is not what it used to be.
Mazda's break-in recommendation is as follows:
No special break-in is necessary, but a few precautions in the first 1,000 km (600 miles) may add to the performance, economy, and life of your Mazda.
- Do not race the engine.
- Do not maintain one constant speed, either slow or fast, for a long period of time.
- Do not drive constantly at full-throttle or high engine rpm for extended periods of time.
- Avoid unnecessary hard stops.
- Avoid full-throttle starts.
Basically, just go out and drive it normally and have fun!
Lance Schall answers the crankshaft question in an excellent article.
We've added a compatibility guide to answer these questions. It'll take some time to make the guide complete, but at least it's a start.
Mostly this depends upon the type of driving you do and the type of weather you do it in. Yokohama AVS Intermediates, Dunlop SP8000, and Toyo Proxes tires have been mentioned as good ultra high performance tires. There are others as well. The Yokohama A-509 and Dunlop D60-A2 have received high recommendations from other Miata owners on the list for everyday driving. Yes some people drive their Miatas in the snow - the Pirelli P190 has been well received as has been the Nokia Hakkapelitta tire - but you must outfit all four corners with the winter tires to realize the benefit.
You have to keep in mind that there is no such thing as "the best tire". It is highly dependent on a number of criteria - not all of which can be achieved in a single tire. You must consider: wet performance, dry performance, snow performance, longevity, price, and one or two other items. A tire that is "best" in one category may be terrible in another. Before choosing tires, you must know which of these items is most important.
You must also remember that "all-season" tires are, by their nature, a compromise. They are merely adequate in all conditions and excel in none. As a result, if you use your Miata as a commuter car or for just buzzing around on weekends and you don't push the car to the limit, an all-season tire may be the right one for you. Just don't make the mistake of thinking you have the best tires. Don't expect to get much traction in the snow. They are a compromise.
Many people mistakenly think the Dunlop D60-A2 is the best tire for a Miata. This is true for a limited set of criteria. It is a low cost, adequate performer that will last a long time. However it is an all-season tire and therefore is a compromise. It represents good value for the money.
The factory tire size for the Miata is 185/60-14. The factory wheels (both steel wheels and alloys) are 14" x 5.5". The 1994 model increased the alloy wheel to a 14" x 6" wheel to better accommodate wide tires. Some special edition and premium packages come standard with 15" wheels and 195/50-15 tires. The steel wheels remain 14" x 5.5". A high performance tire option for the factory wheels is a 195/55-14 sized tire. This will give about a 10mm increase in width without changing the overall tire diameter. (It differs from stock by -1.2%.) Check out the Miata.net Tire Calculator to play around with different combinations.
You can pick up a bit of extra room by removing some of the foam padding from the seat - either from the seating area or from the seat back depending on whether you need to gain space for the legs or for the torso. Additional headroom can be gained by removing the seat adjuster rails and bolting the seat directly to the floor, but the sacrifice in adjustability may not be what you want.
We received the following tip on picking up a bit of thigh room:
As a large Miata enthusiast I have been looking for ways to be more comfortable in my Miata. I have made a very simple modification that has made driving much more comfortable for me. I replaced the arm rest of my '90 Miata, which has the handle that parallels the steering wheel, with an arm rest from a junk Mazda 323 that does not have the handle. (I think that the B2000 truck also has an arm rest with out the handle) This gives me about 2" more clearance for my left thigh both for clutch operation and just seating position while cruising. I filled the hole in the door panel with a black plastic plug that I happened to have from tinkering with bicycles, and it looks great. This will take a little scrounging and some creativity but the change really added a great deal of comfort.
The Miata Owners Manual recommends 7,500 mile oil changes, 5,000 under "harsh" conditions. Consumer Report magazine thinks this is reasonable as well. Some people like to change the oil more frequently as "cheap insurance." Other people are comfortable going longer. We recommend using the "harsh" schedule.
Synthetics are just fine, but engine treatments and other oil additives are NOT recommended. If you live in an area with extreme temperatures, consult your owners manual for oil and other fluid recommendations. Using genuine Mazda filters is highly recommended. If you change your own oil, you probably noticed the little washer on the drain plug. This washer should be replaced EVERY time you remove the plug because it bends when you tighten the plug and may leak if reused.
Recommended interval is different for other countries. Please see your owner's manual.
See the Miata Tops section.
We recommend nothing other than keeping it clean. Just a mild soap and water is sufficient. Be sure it is dry before putting it down, and if the car is new, take care to be sure the fabric folds correctly. Some people use Convertible top treatments, and some swear by Armor All. However the need for "top dressing" is not necessary as it was back in the '60s when convertible tops were made of canvas. Any mild cleaner or protectant should be safe to use. Test an inconspicuous spot to be sure!
Also, you should always use the boot for the top when folded down. This will help protect the underside of the fabric from harmful UV rays, dust and dirt, ad also keep it from rattling and bouncing during those bumpy road excursions. Here are a couple of photos of what can result by not using the boot. Photo 1 Photo 2. Brian Bousman provided a very good photo showing the proper way to fasten the tiedowns.
Also see the Miata Forum FAQ
ALWAYS, ALWAYS!! unzip it before lowering the top. Use a soft, clean towel on either side of the window to protect it from scratches when it is down. Use a good quality plastic cleaner and/or plastic polish to remove scratches and keep the window looking new. Meguiar's #17 Plastic Cleaner and #10 Plastic Polish are highly recommended. There are several aftermarket suppliers for cleaning supplies and 'rear window protectors'
Frequently, Miata plastic rear windows fog over, turn yellow, then turn brown, and become opaque. We don't know why it happens, but it happens. Some people have had success with the plastic cleaners on the market. More than likely, you'll have to replace the window. We received this tip from John Venables which we haven't tried, but it couldn't hurt if you're about to replace the window anyway:
If the PVC window in your soft top is discolored and clouded with age, give it a clean and buff up with standard chrome cleaner (Solvol Autosol in the UK). Sounds drastic but it removes the yellowing and restores visibility.
There are several options to replace the window. The standard Mazda factory replacement is approximately $300. Installation is extra and can be rather involved. Best left to a pro. A competent upholstery shop can do it for under $200 by simply cutting out the old and sewing in a new one. For about $375, you can go with a glass replacement window available from Brainstorm Products. This will eliminate future problems with wrinkling, yellowing, creasing, etc. The minor downside is that you need to be more careful about putting things on the rear shelf. Also, the area is just slightly smaller than the factory window. Finally, depending on the age and condition of your soft top, you may want to replace the entire top. If your top is more than 5 years old, it may be due for replacement soon anyway.
Yes, Mazda markets the hardtop as an accessory. At a price of around $2300(US), they are a bit dear. There are also other hardtops available from sources other than Mazda, often quite a bit less expensive with little or no difference in quality. Expect to pay around $1,500 (US) for a new aftermarket hardtop. Preowned hardtops can generally be found for about $1000.
The Miata hardtop is a universal design. By this we mean that hardtops from any model year Miata will fit on any other model year Miata. In 1992, a rear window defogger was added to the hardtop. If your Miata is an earlier model, you will still be able to use the hardtop, but you will not be able to use the defogger without making several non-standard modifications to the electrical system and wiring.
If your Miata was not originally fitted with a hardtop, you will need to add a few parts. The critical parts are the hardtop latch strikers. Installation is not terribly complicated. You will need to remove the right and left interior plastic trim panels and cut holes to accommodate the strikers that you much purchase. (See below.) Cutting is not too bad - the spot you need to cut is pre-molded into the back of the plastic panels. All you have to do is follow the lines.
You will need to purchase a few parts. The strikers are most critical as they give the hardtop the required rigidity. The electrical parts are necessary only if you want to use the defogger. (If you have a '90 or '91, you won't be able to use the defogger, so there's no need to buy those parts.)
Finally, you may need to get it painted to match your Miata - another $250 (US) or so.
*If you already have a defogger with your soft top, these parts may not be necessary.
Prices shown are Mazda list price at the time this was written. Prices subject to change and dealer markup/markdown.
Also see the Hardtop FAQ
Obviously yes. The possibilities are almost limitless. Any Mazda dealer will sell the factory radio and CD player as an add-on unit. These units are of good quality (for factory units anyway) and are much less prone to theft than other brands. (Especially important in a Convertible!) The Clearwater company is well known for their high quality amplifier and speaker upgrades specifically for the Miata. If you don't have headrest speakers, give them serious consideration. They really make a big difference when driving at speed with the top down. Also see the audio section of Tips from the Garage.
The owner's manual as well as the Workshop Manual both state that three consecutive incorrect attempts at disabling the anti-theft system will render the radio inoperable and that it must be replaced. This is absolutely not true! There is a very simple procedure which will restore your radio to operability. It does not involve removing the radio and requires about 30 seconds to complete.
In the past we had chosen not to publish the code. However, this information was previously released on the net by folks who really didn't think security was important. We believe that poor security is worse than no security since it may lead to a false belief that things are secure when they're far from being so. As a result, we've decided to publish this controversial, yet widely known procedure.
To determine if this radio has been set with an antitheft user code, remove battery power from it for at least 45 seconds. When battery power is restored with no user code set, the radio's operation is immediately restored. If a code is set "cod e" flashes in the radio's display.
When "cod e" flashes in the radio's display after battery power is restored, and you know your antitheft user code, the radio's operation can be restored by following your Owner's Manual "If Antitheft system is Activated" procedure. If you don't know your antitheft user code, or to remove one previously set, follow the same procedure three times entering an invalid 1 to 4-digit user code each time. Once an invalid 1 to 4-digit user code is entered three times, "err" flashes in the radio's display. When flashing "err" displays, the radio is now set to accept the following re-set procedure.
late '95 - Optional on Leather package
'96 - Optional on Leather package
'97 - M Edition with MPSS
(See picture at: http://www.miata.net/garage/msss.html )
To determine if this radio has been set with an antitheft user code, remove battery power from it for at least 10 seconds. When battery power is restored with no user code set, the radio's operation is immediately restored. If a code is set "code" flashes in the radio's display.
When "code" flashes in the radio's display after battery power is restored, and you know your antitheft user code, the radio's operation can be restored by following your Owner's Manual "System activation" procedure. If you don't know your antitheft user code, or to remove one previously set, follow the same procedure three times entering an invalid 1 to 4-digit user code each time. Once an invalid 1 to 4-digit user code is entered three times, "err" flashes in the radio's display. When flashing "err" displays, the radio is now set to accept the following reset procedure.
When displaying "err":
See also:Getting the Most out of your Radio's Security System
Assuming it's the standard Panasonic with the three large buttons in the upper left hand corner for setting 6 pre-set stations, here's the story:
This Miata radio has an internal fuse. It's a 10A regular size automotive type blade fuse that can be gotten at most any automotive parts place. From Panasonic the part number is YEAF02005, F701 for CQLM 191AA.
The internal radio fuse is not push-in replaceable -- it's soldered in. It's located on the hidden side of the audio power output circuit board within the heat sink area. Fuse replacement requires removal of the entire heat sink from the back of the radio and then removal of the circuit board within the heat sink. This red fuse is easy to spot on the circuit board once the board is removed from the heat sink.
When this fuse blows due to high current reversed voltage a protecting diode D702 (Panasonic # YEADDSA3A3) on the power audio output board sometimes goes too. This may also result in one or both of the power output IC's blowing too (Panasonic # YEAMMC13304T, about $25 each) as well as many other parts within the radio and tape deck. So, simply replacing the internal fuse may or may not restore the radio's operation.
The standard 94 Miata radio is also protected by two fuses in the underdash fuse box, room and cigar, so check those fuses too.
Most any radio repair shop should be able to replace your radio fuse and do most of the other repairs that may be necessary. If both output IC's are blown it may be more cost effective to just get another used Miata radio.
The national repair center is:
Parkway, East Syracuse, NY 13057
Note: Jeff Anderson, who also fixes Miata radios to get better headrest sound, might be willing to check it out. See our information on Jeff's radio fix.
The small "gel cell" (well, not really, but that's another story...) battery is manufactured exclusively for the Miata and should be replaced with the factory part. Interstate and Westco also make batteries which, although not an exact fit, are similar in size and performance to the factory battery but at a lower cost.
If you decide to use a different sized battery, (which many people have done with success) be sure to modify the hold down bracket so that the battery is mounted securely. Mazda supposedly has a kit to mount a 'normal' battery in the Miata, but nobody seems to have ever needed one. The original battery lists for about US$120 and has a life expectancy of about 4-5 years.
Before you install a normal battery, be aware of the following: All batteries produce dangerous gases. In most cars, the battery is located under the hood where it can escape to the outside. In the Miata, with the battery located in the trunk, there is no place for the gases from a normal battery to vent. On the factory battery, there is a rubber hose leading from the battery to the outside so that gas does not accumulate the trunk and explode. If you decide not to use a factory battery, you should consider using a container to enclose it that attaches to the factory vent hose. Failure to do so could possibly cause caustic gasses to rust the metal of the trunk, cause an explosion when exposed to heat, cause an explosion in an accident, or worse.
Also see this complete description of the Miata battery.
See your owners manual. In general, 87 octane unleaded fuel is fine. If you have altered your engine timing from factory specifications or made other performance enhancements, you may notice pinging and benefit from a higher octane fuel. Oxygenated fuels and gasahol may cause trouble and the owners manual recommends that they be avoided. Miata Magazine reports that the Miata will loose four horsepower when running on oxygenated fuel. If your Miata is running well (ie., no pinging) on 87 octane fuel, there is no reason to pay for higher octane unless you own oil company stock. You will not get any additional benefit from it.
Just pull firmly and twist.
See the writeup in the Garage section.
The Miata Squeaks and Rattles page will answer this.
If water is leaking in from the driver's or passenger's window near the soft top weather-stripping, try closing the door after closing the window. This forces the window to contact the weather-strip a bit differently than when the window is closed while the door is closed. Another possible source of top leaks may be the seam on the edge of the roof. We know of at least one individual who was successful using a bottle of water repellent "shoe protector" available at most shoe stores. After spraying several coats on a dry area of the top seam, the leaking ceased.
There are two common places a Miata will leak water into the interior, where the top meets the windshield frame, around the windows where they contact the moldings. Leaks at the windshield frame are usually caused by dirty or damaged moldings or the latches not being tight enough. Usually you will notice the top will squeak and rattle if it isn't latched down tight.
A third leak area has been cropping up lately with older Miatas. People have reported wetness in the trunk which can be caused by one of several factors: Dried out weather-stripping around the trunk, a cracked rain rail on the convertible top, or dried out weather-stripping around the tail lights. The tail light weather-strip problem has been appearing more and more frequently on the older vehicles.
If your convertible top doesn't latch securely, or the latches seem to be difficult to close, they may be adjusted improperly. Open the latch and examine the inside. There is a small plastic 'cover' that keeps the latch adjustment screw from moving. Pop the cover off and adjust the screw as needed to get the latches to close smoothly, yet tight enough to keep the top from rattling or leaking. If the latches become difficult to open or close, a small amount of oil on the moving parts should help. Don't over tighten, as this will make the top difficult to close.
There are three moldings that fit around the window, and water can leak either between them and the window, or between them and the top. Each of these moldings is attached to a metal 'track' that is secured to the top frame with two screws. NOTE: The window molding that is closest to the windshield header is held on by two screws, the others have nothing holding them.
See also Service Bulletin on this.
See your dealer, early (1990) Miatas had problems with the switch that detects when you are in reverse. This was a service bulletin some time back, but since the car is out of warranty, its unlikely the dealer will replace it at no charge. The part is cheap, and you can do it yourself, but it does require getting under the car and the switch is located on the transmission in a place you can reach, but can't see. Miata Magazine (Winter 1993) has details on changing this switch.
See the section on Tiedown Hooks as well as the Miata Forum FAQ
Try WD-40. It will remove tar and other petroleum based products from your car without damaging the paint. It also does a good job of removing wax, so remember to wash and wax the area after.
Mike Cantrell contributes:
When trying to remove any stubborn spot, try your normal car wash solution, using a pair of panty hose instead of a sponge before resorting to WD40. I think I saw this tip in Miata magazine as well, it has worked for me several times on bugs, etc, on the nose of our '90 model.
There have been many Service Bulletins. On the Web, the National Highway Traffic Safety Administration has put a summary of all vehicle recalls and service bulletins as well as consumer complaints. This is a summary - not a complete description. However if you suspect one of the problems on the list, you should probably see your dealer and ask about it.
Its a common problem to end up with water in your rocker panels. There are drain holes that sometimes get clogged which you need to check periodically and keep clear.
Check where the jack hooks to the frame rail. (You can find it in you owners manual if your not sure.) Each side of where the jack hits the frame rail is where the drain holes for the rocker panel are located. There is a front and rear location for the jack. Use an open paper clip and wiggle it around until the drain unclogs.
See also the Service Bulletin on this.
Lester Seal, firstname.lastname@example.org
Richard Dekker, email@example.com
John Emerson, firstname.lastname@example.org
The National Highway Traffic Safety Administration is still evaluating options on this issue, however it is known that airbags have saved many lives. Due to legal constraints, dealerships and private mechanics are not permitted to disable your airbag. The NHTSA has issued a final ruling regarding manufacturer's installing disabling switches and a ruling is in the works regarding private mechanics performing the service. If you insist on having it done, you must do it yourself. It is legal for you to do the work yourself. We do not recommend this. However if you refuse to be deterred, you should check out http://www.airbag.net for some interesting information and also check out our own opinions on airbags.
Also, you probably shouldn't read it, but we also have a Miata Airbag FAQ.
Your valve cover gasket is probably dried out and should be replaced. It's a fairly simple do-it-yourself project - just be cautious about the torque on the valve cover bolts. They're in the 7 ft-lb range.
There are a number of possible causes of this. The obvious, which you've probably already investigated, include such things as a stuck thermostat, coolant leak, debris clogging the radiator fins, or an electrical problem which causes the fan(s) to be inoperable. However there is another possible cause which has been seen quite a few times that is not so obvious.
If your car is a '90-94, take the thermostat out and look at the small by-pass hose fitting coming out of the housing. You will probably find some metal shavings partially clogging the fitting. It causes some bizarre overheating problems. These are left over from the original machining of the head and block and will sooner or later migrate to this spot. Check the rubber hose as well, as sometimes they work their way down into it.
There may be nothing wrong. We often see hot engines idling in the 15psi range.
First, check your gauge against a mechanical gauge to determine if it is the engine or just your pressure sensor. If the mechanical gauge also reads the same low pressure then you will need to diagnose it. Make sure the basics are covered such as good oil of the correct weight and fresh filter.
As you can see from THIS PIC the B6/BP oiling system is pretty simple.
1) Oil is picked up by the oil pump
2) sent to the oil filter
3) travels past the pressure sensor
4) splits between the short block and the head.
5) short block leg feeds the rod/main bearings and oil squiters
6) before entering the head it passes through a restrictor
7) head leg feeds the cam bearings
If you are experiencing low oil pressure then the culprits could be
a) bad oil pump
b) stuck open pressure relief plunger in oil pump
c) leaking pickup tube
d) clogged pickup tube
e) out of spec bearing tolerances (rod/main/cam)
f) bad restrictor
g) bad piston squiter
h) cracked block/head or leaking head gasket (either causing pressure to leak to return)
When my wife's Miata experienced the same thing a year ago I replaced the oil pump with a known good used one (taking the opportunity the add a relief valve spring washer). I inspected the pump gears, housing and relief valve for spec. I then changed all rod and main bearings in the block (the oil pan must come off the change/inspect the oil pump so freshening the bottom end with new bearings is only a few more minutes work).
I only got about 5 more psi from all that work so her engine must have a bad head gasket, bad restrict or crack somewhere. Not wanting to put anymore effort in to the 1.6L I opted to build up the 2.3L at that point.
Although 15 psi at idle is low your
engine should survive NA as long as the oil pressure doesn't get much lower
This was a fairly common problem, especially with white Miatas from '90 and '91. There was some process problem, but it wasn't generally acknowledged. Some dealerships a few years ago, as a gesture of good will, took care of the repainting at their expense. But now, those vehicles are far past their warranty period. There is no possible way Mazda or any dealer will, or should be expected, to pay for a new paint job. Bite the bullet and get the car painted yourself or consider trading it for a new one.
Check the bolts again. This time loosen them, and notice there are spacers that have a wedge shape. The spacers need to be pushed up tight, then the bolts tightened down.
I resolved the problem by using contact cement. First clean both the metal and rubber surfaces of all old adhesive residue. Next, practice how the two surfaces will go together. This is necessary since the two surfaces that have contact cement applied can not be pulled apart once they touch one another. Then, simply brush contact cement on both the metal and rubber surfaces. Keeping the two surfaces apart, wait until the contact cement dries thoroughly. Then, taking care, line-up the two surfaces, beginning at the front, and press the rubber surface against the metal surface working your way to the back side. Remember, once the two surfaces touch each other, they are glued together and cannot be re-aligned. This repair will NOT come apart if done properly.
The drain for the evaporator case is probably blocked by debris. Get under the car, and look on the right side of the tunnel near the firewall. There will be a short piece of black hose protruding from this area. A coathanger or a bit of compressed air will work wonders. If the clog is too bad to be loosened this way, you may have to have the evaporator case removed and cleaned.