Ford Thunderbird Super Coupe Buyer's Guide

What this guide will cover:

• Introduction - Background info and SC history
• In Person - First inspection impressions
• Engine Bay - What to look for under the hood
• Inside - Things to be aware of inside the car
• Seller Said - What feedback you might get and what you might hope for
• Start Me Up - Assuming the car starts, these are some of the things you should be aware of
• Test Drive - What to pay attention to when going for test drive in an SC
• Decisions, Decisions - Tips on what to do with what you've learned and how to proceed
• The High Mileage SC - Just a heads up on what to expect if you're thinking about owning one
  
• Introduction

This guide, v4.0, is for the buyer that may not be familiar with the 1989 ~ '95 Ford Thunderbird Super Coupe & 1989 ~ '90 Mercury Cougar XR-7, and is looking for hints and tips as to any particular items that may be wise to note when considering purchase. It is not meant to provide general used car buying assistance and it assumes that a rookie SC buyer has basic automotive knowledge. Note that not all SCs came from the factory with similar equipment, features and options.

The Ford Thunderbird was restyled in 1989 and became slimmer in overall dimensions with a wheelbase nine inches longer than the previous model. Also new at that time was a fully independent rear suspension. Mercury's Cougar is similar, but with different appearance touches. Base and LX editions had a 3.8-liter V6 and 4-speed overdrive automatic. Performance fans had a particularly tempting choice: a supercharged, intercooled variant of the V6 that pumped out 210 horsepower in the Super Coupe (SC), which featured dual exhaust, 16-inch tires w/aluminum wheels, and 4-wheel antilock disc brakes standard. This body style, known as ʻMN12ʼ, ran thru 1997, with the SC ending in 1995. The major years of the SC represent two basic versions: 1989 ~ 1993 and 1994 ~ 1995. The Anniversary model was 1990.

My 1990 35th Anniversary Super Coupe

What are the hidden differences between the ʻ94/95 SCs vs. the early model cars, besides the obvious exterior and interior changes?

The late model cars received many tweaks by the 3.8L Engineers. The rods were improved, the heads were modified slightly, and the crank was altered. Numerous electronic components and sensors were changed, the EEC was updated, and the injectors were raised to 36# vs. 30# on the early model cars. The automatic transmission became “electronic” (4R70W vs. AOD); the manual transmission received slightly different ratios. The ABS unit had already changed to a different style in the ʼ93 model year. The interior received driver and passenger side air bags, eliminating the automatic gliding shoulder belts. The interior changes included a different dash, front airbags, center console and seats, along with a 145 mph speedometer (easily retrofitted to the early model instrument cluster).

The single major reason for the horsepower difference between the early and late model engines is the better internal porting and epoxied rotors on the ʻ94/95 Eaton supercharger. The rectangular opening on the rear of the late model unit is far larger than the oval opening on the early units. Even though it is spun slower than the early model blowers via a slightly larger pulley, it makes the extra HP easily through enhanced airflow capability and increased adiabatic (heat handling) efficiency.

Many people find themselves using the Internet to hunt for an SC. This is a great way to window shop, but it can be important to remember that an online digital photo is a filter through which various details can be simultaneously magnified as well as masked. There is no substitute for walking around a vehicle in person by you or your broker. Decide beforehand if you are looking for a reliable daily-driver or a project.

• In Person

During a first inspection, it is easy to overlook small paint defects, missing interior trim and malfunctioning lights and accessories. It can be a good idea to take your own photos so that you can study more closely at your leisure. Print out this document and bring a flashlight. Donʼt be shy when asking if you can come back to take another look.

Walk around the car and observe if it sits squarely. Is the gap between each tire and fender the same? Check the tires for wear and note the size (driver door sticker has stock tire data). Tires and wheels may have of course changed sizes...ask why.

Does either door sag on the hinges? Are the seams between the body and doors/hood/trunk equal and straight?

• Engine Bay
  

The hood release is inside the car, below the dash, left of the driver seat on the side - pull to open. The (yellow) safety catch is over the passenger side headlight, about a foot from the edge of the fender - raise the hold slightly, reach just inside and slide the release to your left to open. The hood when opened is supported by a pair of gas cylinders and it should stay open without your help. Caution. Donʼt get under the hood until you know it wonʼt suddenly drop and try to close.

Check all three serpentine belts for wear in the form of cracks or missing ribs. Check the belt tensioners for wear via the ʻrangeʼ gauges. Inspect the radiator, thermostat housing and hoses for leaks. Are any of the wiring harnesses intact or have they been opened up/damaged and left to suffer at any location? Note the data on the build tag on the front bulkhead, near the radiator, to see if it matches the sticker inside the driverʼs door and the VIN tag at the windshieldʼs lower edge, driver side. Be sure to jot down the VIN code if you plan to run a CarFax check. Did the courtesy light under the hood work? Is the battery clean and securely mounted? Check the lower front edge of the battery for a wedge type clamp.

Look for broken or missing wiring retainer clips, wiring harness points that have been cut or left open and any grounding straps that may be disconnected (right front of engine motor mount to body is just one).

Check under the car for fluid leaks. Red is power steering and/or auto trans. Black is engine oil and/or brake fluid and green is coolant. The oil filter is located at the lower front of the engine ( sideways at an angle). It is not easy to remove on some cars, especially with bad motor mounts, and it can be common to find oil right below it that may indicate a leak – or just a messy oil change. Deteriorated mounts can also cause issues with power steering lines – even a cracked oil pan. Rev and watch engine to see if it rocks. The intercooler should sit level compared to the frame that holds the rubber air guide.

Check for low levels of auto trans, engine & power steering fluids (dip sticks for these – auto trans dip stick is at left rear of engine) and coolant & brake fluid (viewable tanks). Is the auto trans ʻTVʼ cable grommet on the cable end that connects to the throttle body? Take note of any service stickers. AC systems that left the factory with R-12 have often been converted to 134a.

Check around the nose of the supercharger for fluid leaks. There is a seal behind the pulley that often leaks at higher mileage. If the supercharger is leaking, there will likely be a dark spot on the under-hood sound insulation blanket, directly above where the supercharger pulley resides. Factory pulley here is steel – aluminum is aftermarket and perhaps a different size (up or down), which would modify the boost.

• Inside

The interior is usually easy to check, with most wear showing on common friction points such as door grabs, seat bolsters, carpets, pedals, the shifter and steering wheel.

Note that the front seats will tilt forward without using the release on the rear. This gravity-activated release engages when the car is parked on a hill, as an example. There are two sets of seat belts for the front. The shoulder belt is activated when the key is turned to run, resulting in the upper end of the belt restraining system traveling across the upper inside door/body edge - the other is a manual lap belt. If the shoulder belts are released from their catch at the top, a warning light will be lit in the dash. With the key off and door opened, the shoulder belt mechanism will travel from the driving position to the ʻopenʼ position at the front edge of the door/window - watch your neck when exiting the vehicle. The belt will not move again until the key is turned on. If the mechanisms move slowly and/or chatter, the internal glide track over the door may need to be treated with silicone spray to speed and quiet movement.

The front seats have power for front-to-back and up/down travel as well as tilt of the entire seat. There are also button switches on the outside of each seat that pump up or deflate the lumbar and move the side bolsters in and out. Seat-back angle adjustment is manual with a lever on the side and there is a release lever for forward tilt to aid rear passenger entry/exit. Note the seat backs can be tilted without using the lever, except when the car is on a hill.

There are three sets of lap belts and two sets of shoulder belts in the rear. An optional w/leather 60-40 split rear seat allows either upper section to be released (pull the short straps at the top) and laid down allowing access into the trunk and/or room for lengthy items inside the car. The 1990 35th Anniversary SC has distinctive leather seats with grey pigskin insets and blue piping, front and rear.

If the battery is properly charged and connected, turning the key to accessory should provide power to the windows, seats, door locks, open door/key on chime, radio, powered antenna, powered mirrors and trunk release (not all cars, all years, will have all of these features). If equipped with a fuel door button (glove box early/center console late), the key doesn't need to be on to release the door. Lifting the console lid or opening the glove box at any time should activate a courtesy light in each location. Lifting the driver's door handle should activate courtesy lights on the inside rearview mirror, a light for the keyless entry keypad if installed, along with a ring around the door keyhole, lower inside courtesy lights on the back edge of both doors and in the sides of the upper body in the back.

Vehicle Maintenance Monitor (VMM) - The dash unit that mentions oil changes, coolant level etc. is a module that monitors fluids and helps tracks factory oil change intervals (3000 miles). This is just a reminder for the driver and has no effect on operation of the vehicle. If the indicator says ʻNOWʼ, see the ownerʼs manual for reset procedure. If any of the other indicators are lit, start by checking/trusting those levels under the hood before starting the engine.

Black tape on doors - Many older cars have suffered from deterioration of the black tape used by the factory on the post at the rear of the door on the outside of the car. Some owners replace the black tape, some repaint this area and some ignore it. Other than being a cosmetic issue, most consider it minor when buying a car.

A ʻFirm Rideʼ blinking light in the dash cluster indicates an issue with one or more of the electronically controlled shock actuators. You should hear a mild ʻclickʼ when the switch in the center console is toggled on/off. Number of blinks indicates which corner may have an issue: Left rear (1 click/blink); Right rear (2); Right front (3); Left front (4). Frequently, cleaning the actuator contacts at the top of each shock is the solution.

Moonroof (an option not found on all SCs): Wind or water leaks? Inspect seal around glass and/or plugged drains...one on each corner that drain into the front wheels and rear rockers. The switch has two positions: 1.) Tilt up at rear. 2.) Slide roof open/closed. Later model SC's have a two-stop mechanism that allows partial vs. full open positions.

The sun shield will retract with the glass when opened, and move out within reach when the glass is closed. It must be then fully closed/pulled forward manually. Check the air deflector at the front. It should spring up slightly when the glass is retracted. The parts are fragile and if not already broken, treat the assembly gently when inspecting - don't use force to see if it lifts up.

Headlights: Headlights flicker? Most likely needs a headlight switch. Check the condition of the plastic headlights for yellowing, etc. New are available at a fair price.

Headlight dimmer/auto off switches - (see below).

Fog lights should work when headlights are on low beam/key on with an indicator lamp in the dash. A switch that does not light up it's ʻOnʼ indicator is most likely dirty inside and/or burned out.

It is a very common problem for the odometer gears in the speedo head to break, which causes the odometer to stop accumulating. It is not that difficult to fix, and a new gear is approx. $50, but the tell-tale sign can be the trip meter sitting at 000.0, since once that is reset after the gears break, it also will also no longer turn. If you notice the trip meter sitting at 000.0, it could be because someone hit the reset button recently, or the gear failed and miles haven't been counted since...best way to check is to test drive the SC & take note to confirm the odometer and trip meter incremented during the drive. If they haven't changed, then the actual mileage on the car could well be higher than what the odometer is showing. Try not to press the trip reset while the car is moving.

• Seller Said

Occasionally, the seller claims ʻ these cars are rareʼ. Outside of '90 5-speed Anniversary models and color changing '95s...not yet...smile and keep looking.

If the seller mentions head gaskets, understand that many cases of head gasket failure are due to incorrect modifications, abuse and/or poor maintenance. Think money...and remember to use the Internet, factory manuals, etc. for more information on this heavily discussed topic.

Typically, blown head gaskets are not a big issue on their own. As long as the gaskets were replaced quickly after they blew, the repair should be fine. It is only if the car sat for a long time, and then repaired, where the new owner is likely to have problems with a spun bearing and/or other more serious issues.

A word about rust. While any used vehicle can suffer from rust, a common problem on SCs from areas such as the East coast, a quick look inside the rear wheel wells, inside the lower skirt area shows if there is rot. Underneath the nose on the hood is a also good spot to check for rot. The best method is to put the car on a lift and examine the undercarriage.

Also, see if the front clip has been replaced in a possible accident - look for any old color under the hood - I think the VIN is there as well as under the front glass on the driver's side. ʻ64Rʼ is an SC.

An SC has three main computers that may give up codes that may or may not agree with what the seller claims: 1.] Main: Engine fuel, air & ignition management 2.] ABS (brakes) 3.] Ride control.

All three are capable of providing feedback via warning lights on the dash and/or via codes using the factory diagnostic tap under the hood (EEC) or in the trunk (ABS). All three are also covered extensively in factory manuals and on Internet sites, forums, etc. Search on Ford ʻEECʼ. Early SCs are OBD-I and late are OBD-II.

Ask or check for an ownerʼs manual. Note there is a separate manual for the premium sound system. If the car doesnʼt come with either of these, pick up a set off eBay (also try to get an EVTM and factory repair manuals) and/or use Internet forums & docs to learn. Youʼll want to know such things as how to set the clock in the radio, reset/use the VMM and how to use/adjust the headlight controls.

Is it real? Note that a genuine set of SC heads have ʻSCʼ cast into them. 1990 35th Anniversary models should have a tag on the radiator crossmember that says ʻ35thʼ.

• Start Me Up
  

Turning the key to ʻonʼ should light up all indicators and warning lights in the dash gauge cluster, as well as the VMM (if installed) over the radio. There is a line of warning lights along the bottom of the cluster, as well as two in the tachometer, below the ʻpremium fuelʼ warning text. The yellow up arrow is an upshift light and all SCs have this regardless of transmission type. In addition, you should hear chimes (and see a 'Door Ajar' dash light), which can include door open and key on. Test the power door locks using the switches on both doors.

When shutting down, there is a chime that sounds when the headlights are left on and/or when the key is left in the ignition with the driver's door opened. You may also hear ABS or fuel pump noise/chatter when turning the key on (along with two brake warning lights in the dash), which should go away quickly as the systems build and hold pressure. Now is a good time to test the tilt wheel mechanism - make sure it doesn't tilt unless the lever (right side) is pulled backwards.

Note that some early SCs need to have the foot brake applied and have the car in Park or the clutch depressed, before the starter will engage when you turn the key to start the engine. If the car starts and idles properly, all warning lights should go out (if the parking brake is applied a warning light will stay on). If the antilock or brake warning lights stay lit beyond a minute, take note and watch for other indications of brake related problems, as there is most likely a brake system issue. Again, think money...

Once the engine starts, check the vacuum/boost, tach and oil pressure gauges for activity. Listen for any knocks, belt scream etc., keeping in mind that a distinctive high-pitched whine, particularly with the hood open, will be heard coming off the supercharger, which is normal unless pronounced, in which case such a rattling sound could indicate excessive wear and/or damage. A honking goose sound when returning to idle indicates a failed IAC (idle air control).

Car should start and idle without intervention from you, with the rpms hanging a bit high until the computer decides all is well and lets the engine idle down normally, such as 650 rpm in drive. If it takes more than one try to start, and/or if the engine stalls instead of idling, repairs could run from simple and free to complex and expensive. Same goes if the engine coughs when driving around. Watch for warning lights and/or erratic tachometer. Use a code reader before making chance repairs. Changing spark plugs in an SC is considered a bothersome chore - this can lead to delayed replacement of both plugs and wires, which can then lead to poor running and performance. Without getting into the gory details, the list of things that can lead to a poorly running engine is not short. Again, repairs should begin by reading engine codes, and tea leaves - tossing a few chicken bones never hurts as well. What those codes mean exactly can be found on the internet, or asked about on SCCOA.com. Don't just expect to be able to throw parts at a problem with these cars. Know before you spend money.

• Test Drive

Driving the car should allow you to determine if basic systems such as lights, transmission, brakes and steering function with or without exhibiting trauma. Is the steering wheel oriented correctly? Does the steering feel loose, or tight at one point but not another? Are there any clunks, pops, or squeals when the steering wheel is turned from side to side? Does the car travel and brake in a straight line on a level road? Any scraping noise when the brakes are applied? Any warning lights lit or blinking in the dash? Does the trip meter in the speedo work? If the engine temperature gauge seems to ride low and/or move quickly at times, the usual culprit is a loose/dirty push-on connector at the sender, rear of the thermostat housing on the top of the motor.

Boost on a stock engine should be 10 to 12 lbs. and vacuum should be 15 to 20 in. Listen for any rattles coming from the supercharger. A mild whine under full boost is normal. Does the engine start on the first try and idle without needing to coax the throttle? Does it accelerate smoothly without missing? Does it build boost with confidence and shift without hesitation or missing a gear? Note any auto transmission or clutch slippage. Be sure to try reverse and of course donʼt forget to check the heater, defroster, and air conditioning controls and operation.

Running the AC should also turn on the electric fan at the back of the radiator – if not, and the AC compressor clutch won't stay engaged, the system could be in need of a recharge and/or repair. The switch for the rear window electric defroster will turn itself off when the heating element warms up.

When inspecting the body, look for rust, poor repairs and such high-mileage** indicators as excessively worn door hinges. Do the doors sag or move if you lift on them or do they open/close with difficulty and don't seem to fit correctly in their openings? Inspect the door seals for excessive wear or damage. Check under the nose and tail for damage to the skirts and any missing items such as chin spoiler or cooling air diffuser pad at the front of the engine. Examine all glass for cracks and/or missing seals and trim.

A wobbly inside rearview mirror is frequently due to a loose set screw that can be reached by removing the mirror and tightening the hex screw on the mount to the glass.

SCs came with different combinations of radio/tape deck and CD player. Be surprised if the radio makes sound in any of the earlier models. On JBL equipped models, the audio and sub-woofer amplifiers and 6” sub-woofer are in the trunk.

Open the trunk with the key and check the spare, jack, wheel lock if so equipped, etc. Note the condition of the trunk liners and the rubber gasket for the lid. Check for signs of any moisture. If you buy the car, ask the seller for the code if it came with the keyless entry option (this 5- digit code is also on a sticker inside the trunk lid). Use the code to test unlocking the driverʼs door...press 3 to unlock the passenger door and 5 to pop the trunk right after entering the unlock code. Pressing the two last buttons at the same time should lock the car doors. Test a key in both door locks. The ignition and doors should use the same key...different from the trunk key.

• Decisions, Decisions

At this point, you should have collected many impressions about the car. This is a good time to clear your head and decide if you want to engage the owner in an extended conversation concerning specifics. If you are comfortable with your own ability and mechanical knowledge to enter into such a conversation, you no longer need advice on how to proceed. If you are not, take notes of what you've found and what the seller said - consider not asking too many questions during one visit and try to find time to think things over before you make a decision. Consider asking for opinions online, using forums*, etc. If you do go online for advice, be sure to also provide basics about the car, such as year and miles along with your notes and links to any photos. Keep it simple...just the facts - explain your motives, budget, time-line etc.

In some scenarios, you may not have access to the owner, in which case you might have no one to provide information or answers to your questions. It may be wise to consider paying a mechanic to inspect the SC in question, preferably one that knows SCs. A CarFax report can be a good investment also. In some cases, you can hire a local broker to not only check the car out, but to handle price negotiation as well, as if they were buying the car for themselves.

• ** The High Mileage SC

High mileage (175k+), poorly maintained SC's typically will need just about everything replaced to have any confidence in them later on. This goes for examples that have been sitting for a long time and subject to 'death by storage'. These cars benefit from being driven.

This is a general list of what might need attention:
• Clutch & clutch master and slave cylinders
• Flywheel work & rebuilt transmission
• Replace engine motor mounts
• Rebuild the motor if replacing head gaskets
• Exhaust work including new catalytic convertors and O2 sensors
• ABS pump, relays, accumulator
• Plugs and wires
• Wheel bearings
• Radiator
• New steering rack, suspension control arms and/or bushings (front & rear)
• New accessories (alternator, power steering pump, a/c compressor)
• Suspension...bushings, shocks, etc.
• Not to mention the electronics, which can suffer separately or together, from bad or missing ground cables to faulty connections suffering from corrosion, water damage and plain abuse.
• All fluids changed, including the supercharger oil, rear differential oil and limited slip diff fluid - SCCOA.com has the details.
• Rust can be a big factor, depending on what part of the country the car has lived in.
• Don't buy a parts car thinking you can easily put it back on the road.

Resources:
*Online: SCCOA . com ...from there you can find tips, parts, vendors and like minding owners.

Notes:
- This guide was originally written in 2008, when it was PDF'd and put online via a rented server (v1.0), then revised as a document via Google Knol in 2010 (v2.0), which closed in 2012. It was later moved to eBay (v3.0) in 2016, where guides were discontinued as of April 2018. v4.0 will be the only version available publicly after 4.2018.
- As this content is locked, please read any followup comments below, from me, for any updates, edits, corrections, changes, etc.