In addition to the previously offered Eldorado coupe and special edition Eldorado Biarritz coupe (option code YP3), a special edition Eldorado Touring Coupe (option code YP5) joined the series for 1991.

• As with other Cadillacs, anti-lock braking became standard on Eldos in 1991.
• Powering the coupes was the 4.9-liter V-8 mated to the 4T60-E electronically controlled four-speed automatic transmission with overdrive.
  • The 4.9-liter V-8 with port fuel injection improved the Eldo's 0-60 mph time to 8.2 seconds over the previously used 4.5-liter V-8.
  • The transverse-mounted engine was comprised of an aluminum block with wet, cast iron cylinder liners and cast iron cylinder heads.
  • It had a compression ratio of 9.5:1 and needed premium unleaded fuel with a minimum octane rating of 91.
  • The 4.9-liter V-8's functions were controlled by Cadillac's GMP4 Powertrain Control Module(PCM).
  • This 64-kilobyte on-board computer sensed vital operating conditions, including
    • engine rpm
    • intake manifold pressure
    • air temperature
    • outside air temperature
    • coolant temperature
    • exhaust gas oxygen content
    • throttle position
    • vehicle speed
    • accessory load level
    • brake operation
  • The PCM also functioned as a data storage system for service technicians to diagnose malfunctions.
  • Eldorado coupes also received new focused engine mounts that aimed the mounts at the engine/transmission torque axis, which aided in isolating engine noise and reducing vibration.
• Computer Command Ride became standard equipment.
• Also new was the exterior color Polo Green, upping the total to 16 colors for Eldos and 15 for Biarritz.
• New options included a heated windshield system that melted frost and ice five times faster than a conventional defroster and a Security Package that included remote keyless entry, automatic door locks with central door unlocking capability and theft-deterrent system.
• Eldorado's Body Computer Module (BCM)--the heart of the car's sophisticated electronic information system--also provided driver and diagnostic information. The BCM also monitored and controlled functions such as air conditioning, Twilight Sentinel headlamp operation, theft alarm and electric cooling fan.
• Eldo's exhaust system featured a new wide-oval catalytic converter that provided 35 percent less restriction than the previous year's unit. The Touring Coupe had dual exhaust pipes with a specific rear valance and rocker moldings.
• The Touring Coupe's final drive ratio was 3.33:1, and its suspension provided a more "international feel" of driving. This suspension package included a 23mm diameter front stabilizer bar, 16mm diameter rear stabilizer bar and 16-inch styled aluminum wheels with Goodyear Eagle GTA P215/60R16 tires.
• The steering system was modified to include a quicker ratio (2.97 turns lock-to-lock vs. 3.13) and a higher effort steering gear compared to the standard Eldo.
• The Touring Coupe's coachwork featured body color front and rear fascias and rocker moldings, all with black bead edging. Side mirrors and door handles were also body color.
• The Touring Coupe also featured a grille-mounted Cadillac wreath-and-crest emblem. A cloisonne emblem highlighted the rear decklid, while Eldorado script was dropped from the fenders and decklid.
• The Touring Coupe also received specific taillamp treatment and offered six exterior colors: white, black, bright red (crimson), polo green, medium slate gray metallic and black sapphire metallic.

Regarding the 1991 Touring Coupe (option code YP5), there are few changes on the outside, although if you see one in Polo Green, you'll know it's a '91. The big news is all under the sheetmetal. First of all, the aluminum V-8 has been enlarged to 4.9 liters and 200 bhp at 4400 rpm, while the torque jumps to 275 lbs/ft at 3000 rpm. Meanwhile, the more powerful engine is marginally more fuel efficient: 16 mpg (14.7 l/100 km) city and 26 mpg (9.0 l/100 km) highway according to EPA. It's mated to a new four-speed automatic transaxle with overdrive, viscous clutch, and electronic shift control. Not only that, a new standard Computer Command Ride System boasts three automatically selected damping modes -- comfort, normal, and firm -- for better ride and handling under all driving conditions. And finally, an uplevel Bosch II antilock braking system has been made standard. All of the improvements are aimed directly at the driver, enhancing what was already a very good package. Acceleration from 0-60 mph has been cut to 8.2 seconds, Cadillac claims, though top speed remains a computer-controlled 125 mph.

Cadillac was adamant that the Touring Coupe is strictly a limited-edition model. That should help its prospects for collectibility in the future, while the excellent engineering will make it more than pleasant to live with until then. There's little to choose from between the '90 and '91 TC style-wise, but at least the Eldorado's smaller size looks friendlier to most eyes in 1991 than it did in 1986. The '91, however, is clearly the better choice because of the engineering enhancements. Even so, the '90 is no slouch, and is worth considering. Grab one now and enjoy it for the next 15 or so years at used-car prices. Either way, you'll likely be happy that you selected an Eldorado Touring Coupe. Motor Trend called the 1982-85 generation TC a "truly impressive handler for a car of its mass." For the 1990-91 models, there's less mass, even more impressive handling, and a lot more go when you step on the gas. How could you go wrong?