911 Universe | USA Porsche 911

1989 Carrera 4 (964)

1993 Carrera 2 Cabriolet (964)

1995 Carrera Cabriolet (993)

1996 Carrera 4S (993)

1997 Targa (993)

Porsche introduced what we consider the late-model 911s in 1989. The first model available in the United States based on the 964 platform was the 1989 911 Carrera 4. Porsche proclaimed the car an all-new model, as 85 percent of the parts were new. The look of the new model, however, was largely unchanged — with the exception of smoother bumpers, skirts, and spoilers.

For the 964, the traditional flat-six was increased to 3.6 liters, producing 250 hp at 6100 rpm. In addition to all-wheel-drive and new suspension, the C4 had all-wheel ABS and power steering. For 1990, Porsche made the 964 platform available in two-wheel-drive as the 1990 Carrera 2, replacing its 1984-89 Carrera 3.2 with a car costing $8,000 or about 15 percent more. Coupe, Cabriolet, and Targa versions were available with the standard transmission or the new, optional Tiptronic automatic transmission that offered the driver control of gear selection as well as traditional automatic shifting.

In contrast, when the 993 was introduced as a 1995 U.S. model in the fall of 1993, it was 30 percent new, much different looking, and $5,000 less than the car it replaced. Styling changes for the 993-based 911s were more aggressive than the 964 revisions. To some eyes, the vast technical improvements the 964 made over previous 911s did not outweigh its somewhat bulky lines. The 993, on the other hand, has generally been met with favor in Porsche circles.

At long last, the 993 engine introduced hydraulic lash adjustment for the valves and power was increased to 270 horsepower. A new multi-link rear suspension contained in a subframe was introduced, improving ride and handling while managing to be quieter than previous 911 suspension systems. Other notable improvements were made in the transmission and brakes. The 993 introduced a six-speed version of the G50 transaxle as well as a more advanced Tiptronic. Larger front brakes, larger pad surfaces, and cross-drilled front and rear rotors improved the already unmatched braking of the 911.

In 1995, Porsche introduced a new Carrera 4, now based on the 993 platform. The new, 993-based Carrera 4 had a simplified all-wheel-drive system that used a viscous coupling and a central shaft to send power to the front differential. Most considered the new system an improvement over the previous system, as it is far more transparent in operation than the 964 system, which induced quite a bit of understeer and made the 964 feel like a front-wheel-drive car.

For 1996, Porsche AG?introduced two notable models, the Targa and the Carrera 4S. The new Targa was no longer the folding targa-top 911 that had been available for nearly three decades. The 1996 911 Targa offered a sliding glass panel in place of the standard steel roof of the coupe. At the touch of a button, the glass dropped down and slid back to a position under the fixed rear window. The Carrera 4S featured the 993 Turbo’s bodywork (less the rear wing), 18-inch wheels, suspension, and “big red” brakes. Power for all 1996 non-turbo Porsches was up to 282 hp dü to a new VarioRam induction system. For 1997 and 1998, the final years of the 993, a rear-wheel-drive Carrera S was added. It paired the C4S’s?body with the regular Carrera’s suspension, brakes, and 17-inch wheels. Black brakes, a twin-grill decklid, and subtle gray trim inside and out made it easy to spot this air-cooled swan song.

What to Buy?

The 1989–98 911s still have a lot going for them. There’s a wide variety to choose from, with coupes, Cabriolets, and two types of Targas. There are two-wheel-drive and all-wheel-drive models. Porsche introduced its first trü automatic transmission for its 911 with the 964, so there are even “commuter cars” for those who spend time in heavy traffic. For those after something different, there were several limited-production 964s: the wide-body 1992–93 America Roadster, the wide-body 1994 Carrera 4 coupe, the stripped-down 1994 Speedster, the sporty 1993–94 RS?America, and the almost-raced Carrera Cup USA. All of these are sought-after among buyers and cherished by owners — and thus command hefty premiums over the regular 964s.

Expect to pay more.

As nice as these last of the air-cooled 911s are, they do have the potential for mechanical problems. There were a few problems with 964 engines worth mentioning. Cars built in 1989, 1990, and 1991 — up to engine 62 M 06836, M64.01 for the manual-transmission cars and 62 M 52757, M64.02 for Tiptronics — didn’t use head gaskets and were susceptible to cylinder head-to-cylinder leakage. To fix this, Porsche modified the cylinders and added head gaskets. Only a very small percentage of early 964s leaked. Porsche updated any 964s still under warranty that leaked if they were wet to the touch, but not if they merely showed signs of leakage in the past.

The 964’s ignition distributor drive belt can fail, as well. If it dös, the second rotor for the second set of plugs will no longer turn. With the rotor stopped, every time the ignition fires it fires the plug closest to where the rotor stopped. The additional misfiring on that cylinder causes detonation and, eventually, damage to something in the cylinder. Porsche’s fix was an updated distributor with an improved belt and a hose from the blower to cool and evacuate ozone in the distributor.

Dual-Mass flywheels were introduced in 1990. The original Freudenberg DMF?proved problematic in the 911, so it was replaced in May of 1992 by the “LUK” DMF, which seems much more reliable. The flywheel change was made at engine number 62 N 01738.

Finally, the 964 all-wheel-drive system was extremely complex compared to other systems of its day, as well as the 993’s setup. The 964 used a transfer case to send power to the front wheels via a planetary gear drive that works in conjunction with the transfer case’s electro-hydraulically controlled multiple-plate clutch pack and the rear differential’s transverse lock multi-plate clutch set. Lateral load and speed sensors, along with lock controls, are integrated, too. The 993’s system is far simpler, with a viscous coupling to the front differential. While it isn’t as responsive as the 964 system and is less effective in the snow, it is better for normal driving. Predictably, there are serious financial downsides to the 964’s “Sputnik II AWD” system. The lateral and acceleration sensors cost over $1,000 each and seem to require replacement more often than we’d like to see. Dozens and dozens of parts, lines, solenoids, control units, pumps, and more were deleted by the 993 system, saving a lot of weight and thousands in maintenance.

While the 993s have been mostly reliable cars, time and miles have revealed their weak points, too. Porsche did recall the 993s for an engine wiring harness update, and we’ve seen Check Engine light problems in some cars that result from premature valve-guide wear. This problem applies mainly to the 1996–98 993s with OBD II, and occurs when prematurely worn valve guides cause problems with the secondary air-injection system and/or the OBD II systems. When it happens, the cars will not pass emissions testing. One solution is to pour a solvent into the SAI?ports and hope it will unclog them. The other is to do a top-end rebuild — an expensive proposition.

As with any used car, I recommend having a pre-purchase inspection done by a qualified mechanic. This is even more important with these cars because they represent a significant investment and can be very expensive to repair. Basic items to have checked are all seals, suspension, brakes, wheels, tires, steering, and drivetrain. Anything that needs to be repaired should be written down on a cost-of-repair estimate and factored into the price of the car.

With a careful eye and proper inspection, it is possible to buy a very nice 964 or 993 that will provide pleasant and reliable driving for many years to come.