Z32 300ZX Buyer's Guide

Buying a car can be stressful, new or used, sports car or family car. Do the homework you would for any car first, then go through the points below. They're the Z32-specific things that can explain why that deal of a lifetime is too good to be true.

Before you go

• Know what you're looking at. Sellers often believe a car is, say, a 1990 when it's really a 1991. When in doubt, check the VIN: the 10th character is the model year.
• Make sure the VIN on the dashboard matches the VIN stamped into the firewall. If they don't match, the car may have been stolen or rebuilt after an accident.
• Be sure of why you want the car. For performance, buy a Twin Turbo. Converting a non-turbo car means replacing a great many parts and costs a lot of time and money.
• If there are maintenance records, look for a recent timing belt change. If there isn't one, or the records don't add up, plan to replace the belt as soon as you buy the car.
• If you can, get in touch with a previous owner and ask why they sold it and whether it had any unusual problems.

Body and underneath

• Look for the usual signs of any used car: rust, accident damage, poor bodywork and poor maintenance.
• Check under the car for damage to the front frame rails. Bent rails usually point to a minor accident, often a curb strike. Have an alignment shop make sure it can still be set to factory specifications.
• Look at the A/C condenser through the front bumper, just ahead of the radiator. It should be flat and straight. A bent condenser may still work, but it suggests a minor front-end accident.
• Check that all the glass is the same brand. A mismatched pane can mean an accident or a break-in.
• If you can, check the engine, transmission and differential mounts for separation. It usually isn't serious, but it causes noises and is a job you'll have to do later.
• Take the car through a brushless car wash. The high-pressure jets find leaks, which are common where the door glass and T-tops meet the roof.
• On 1990 cars, leaves and debris can collect in the evaporator housing and block its drain, letting water into the passenger footwell. The fix is a revised cowl screen.

Engine

• See the car first thing in the morning, with the engine completely cold. A warm engine can hide weak batteries and hard starting.
• Check for any sign of an engine fire: melted insulation on the underside of the hood or melted wiring.
• Remove the oil filler cap and look at the underside of the valve cover for sludge or particles in the oil. Black oil only means it's due for a change. A cheap generic oil filter may mean the owner cut corners elsewhere too.
• Cars built before 7/90 can have defective valves that start tapping after a while. Twin Turbos with engine numbers below 619550 and non-turbos below 777599 may be affected.
• The power transistor unit (PTU), which fires the coils, is prone to failure. Early cars were covered by a voluntary recall in the US.
• The knock (detonation) sensor, or really the wiring to it, is prone to failure. The sensor is mounted between the cylinder heads, so replacing it is a big job.
• Leave the car idling and smell the exhaust. A rotten-egg smell usually means a worn out or clogged catalytic converter. Blue smoke means oil burning, white smoke means coolant (often a head gasket), and black smoke means it's running rich. Listen for misfires too, which can point to worn ignition parts.
• Faulty O2 sensors hurt fuel economy and can be hard to diagnose.
• On a Twin Turbo, watch the boost gauge at idle. The needle should sit at the far left. If it sits nearer the middle, the engine may have low compression or vacuum leaks (usually with a rough idle too).
• Oil pressure should be 30 to 60 psi when driving and 10 to 15 psi at idle.
• Twin Turbos are much more prone to overheating than non-turbos. Take a long test drive, keep an eye on the gauges, and look in the wheel wells for signs of coolant being blown out.

Drivetrain

• On manual cars, the hydraulic clutch system can leak or pick up air, giving a slipping clutch or soft pedal. A little throw-out bearing noise is normal for 30,000 miles or more, but a lot of noise means a clutch job is coming.
• Avoid 1989 to early 1991 automatics if you can, especially high-mileage ones. The early automatic transmissions have a design flaw that makes them overheat.
• The driveshaft center support bearing tends to fail between 70,000 and 100,000 miles.

Brakes, steering and suspension

• On the test drive, find an empty lot. Accelerate hard and look for smoke from the back, swerve a couple of times, and brake hard. A shimmy under braking points to a rotor, ball joint, steering linkage or alignment problem. The stock rotors on 1991 and later cars warp easily.
• If you can take a wheel off, put two lug nuts back on without the wheel and try to rock the rotor. If it feels loose, something needs a closer look.
• The brake master cylinder on 1989 to 1991 cars tends to start leaking at around 40,000 to 50,000 miles. The replacement part is a revised design.

Not sure which year you're looking at? The Z32 registry decodes a VIN, and the color chart tells you whether the paint and interior are original for that year.