What are common problems with 1986 Nissan 300zx?

Answer 1

I have owned two 1986 300zx's. First one is still running after 250K miles and never had any issues except general maintenance repairs over the years.

Second one has 60K miles and is selling for $20K only has cold start idle problem when weather is warm. We can fix that! Runs the bomb! --rosie

Answer 2

First off, I've owned two first gen 300ZX's. Personally, they are very high maintenance vehicles. My first was a 1985 300ZX. My second is a 1986 300ZX. I can currently tell you that you need a large pocket book full of cash to own one. I also own a 1979 Datsun 280ZXR which I've owned for 14 yrs and have modified it extremely. It however is very reliable. The L28E engines are bulletproof. Easy maintenance engines. Change the oil and go. When and if something were to go wrong with it. I know exactly what is the problem.

However, with the 300ZX's they have way too many sensors and modules and it is very hard to diagnose any problems that occur yourself. I am personally going through an issue now, in which so many forums indicate the issue, but none indicate the fix. I've already tried the suggested parts to fix the problem and it hasn't fixed anything. Still the same problem! Ugh!

Anyhow, it appears that most of the issues with these Z's are Digital Dash. You can find forums that say it's the control unit under your right knee. That it is. Take it out and un-solder the connections and re-solder them yourself and everyone hasn't had any problems since.

Secondly, there is an issue with the distributor, crank angle sensor. Which is located inside of the distributor. This small electronic part is a Hall Sensor for crank timing. If it goes bad. You will get no spark whatsoever. Because it sends a signal to the computer telling it to fire the Ignition Module, to fire the Coil. From my experience. These are all part of the same. Distributor, CAS (Crank Angle Sensor), Coil and Ignition Module. If it's not the CAS, then it could be the Ignition Module or a bad Coil. Some others say that it could be a MAF sensor or Mass Airflow Sensor that would shut the car completely off. Or a Air Regulator clogged. Then you have a TPS (Throttle Position Sensor), which is mounted onto the throttle body. Which control speed on or off. You also have your oxygen sensor that on some vehicles, wouldn't allow it to run at all. I've also seen radiator issues. Timing belt vs. Timing chain on a 280ZX. The thermostat and water pump must be changed when doing a Timing belt. Cause it's all right there. Not easy to do just one without tearing it all apart again, to do the other.

The computer on my 280ZXR only control pulse to the injectors and coolant temp to run the car. Otherwise, I haven't any other sensors or modules to worry about.

If one can afford the maintenance on a 300ZX, then I've seen these engines go 400k plus miles on the stock internals. VG30E engines are bulletproof!

When buying a first gen or Z31. The things to notice are leaks in the T-tops. Rust in the undercarriage. Anything mechanical. I've seen issues with the Temp Control not working correctly. Parts are extremely hard to find. So make sure that it's above a 50/50 deal. Meaning that is it going to cost you more to fix the issues it has vs. how much could you get out of it when you get tired of fixing the issues. Seriously folks, these Z's aren't in high demand. I'm specifically talking about the N/A's. The Turbo may bring a little more worth. One original Z with 10k original miles might bring 10K. One with 40K might bring only $3,500 to $6K. One with (like mine) with 140K original, I purchased for $1,400.