It’s been nearly four months since I last checked in about my project Nissan 300ZX Twin Turbo. I’ve been trying to drive the car more often, because that’s what cars are for: to be driven.

I can report that it has been a solid vehicle overall. Yes, solid... aside from it randomly not starting and leaving me stranded in parking lot on a 100 degree day. Let’s not forget the puddle of brake fluid originating from who knows where or the smell of antifreeze that lingers when the car is warm. Oh, and also, there’s that saggy plastic belly pan that allows the bumper chin to scrape across anything resembling an incline.

OK, so maybe it hasn’t been completely smooth sailing since I last wrote.


Let’s take a look at the stuff I had to fix, and what it cost me to drive this car sparingly over the past four months.

Don’t Get Me Started

I must confess, this first issue I should have seen coming. On more than one occasion, the Z has refused to start. I would turn the key to “On”, all dash lights would illuminate like normal, then upon turning the key all of the way to “Start,” nothing would happen. Not even a solenoid click to be heard.


Now, a normal human being would become concerned at this point. Even if the car were to start on the second try, they may lose all confidence in the vehicle’s starting ability.

I found that on the second starting attempt the car would stir into life like nothing was amiss. What did I think? “Oh! I must not be depressing the clutch pedal all of the way!”


That came back to bite me. At the least opportune time on a scorching-hot afternoon during my lunch break, the car wouldn’t start. No matter how many times I turned the key, no matter how hard I slammed the clutch pedal, no matter how many prayers I sent up to the car gods, the damn thing wouldn’t start. I should have seen the writing on the wall.

I did a flurry of an investigation and narrowed my symptom down to two probable culprits. Actually, there were probably numerous potential culprits, but in my mind these two made the most sense: the clutch safety switch and the starter relay.


How did I arrive at this conclusion? It was the lack of noise, specifically absence of a “Click!” when the key was turned to “Start.” To me, this meant that the relay that sends power to the starter motor was not engaging. The clutch safety switch was more of a “while I’m in there” part replacement, but a faulty one could certainly give a similar symptom.

Did I physically diagnose any of these parts before replacement? No. I am guilty of the DIY mechanic’s cardinal sin: Throwing parts at the issue. Here’s the deal though: It’s about opportunity cost.


I did enough research to at least get in the ball park of the problem, so I had a reasonable expectation that either one of these two parts was the issue. I decided to just spend the $40 to buy new parts and install them immediately. I could have spent a couple of hours diagnosing, but with time and effort required to get to each part, I might as well put new ones in. Is this usually a good approach? No, but sometimes it does make sense.

With the new parts in hand, I threw them into the car. I have now driven the car for over a month since and I haven’t had a single starting issue. Hot days, cool mornings, long drives, you name it, the Z hasn’t let me down.



Parts Cost: $40.56

Give Me A Brake

About two months ago I noticed a puddle developing under the car, near the driver’s side floor board. It was clear, odorless, and had an oily construction. It could only be brake fluid.


Following some poking around in the engine bay, I discovered that the brake master cylinder reservoir was cracked in multiple spots. This was one of the parts that I replaced during the original overhaul. How does that even happen, especially to a new part? Further the investigation went...

I found that a rather thick vacuum line had been pressing up against the reservoir, and this added pressure mixed with the immensely high under-hood temps, caused the reservoir’s plastic to become brittle and crack. Great.


The brake master cylinder’s next-door-neighbor is the clutch master cylinder. Wouldn’t you know it? It was leaking too. This leak appeared to be coming from the seal at the back of the unit where it met with the firewall.

Fortunately for me, the engine didn’t need to be removed to replace these items. I decided it was a good idea to reroute the suspect vacuum line so that it no longer was in contact with the brake fluid reservoir. With the new brake fluid reservoir and clutch master cylinder installed, the fluid leaks were put to rest - for now.


Parts Cost: $94.06

Pop Goes The Weasel

I had noticed a faint smell of antifreeze when the car reached operating temperature. I had mentally prepared for the worst. There are coolant lines going everywhere in the engine bay, and most are hidden requiring significant disassembly to access. I figured I was going to have a big project on my hands.


Luckily, it was simply the radiator cap seal that was giving up. There was a small drip of antifreeze originating from the cap which was trickling down the side of the radiator. This was a dead giveaway. This was one of the few parts that I didn’t replace on the original overhaul.


Repairs don’t get much simpler than this, and on a 300ZX, this sort of fix is an absolute blessing. With the new radiator cap screwed on, the scent of antifreeze was gone.

Parts Cost: $17.17

Scraping By

The bumper chin was finding a way to scrape on just about anything you put in front of it. While the car sits low, it isn’t that low. I felt I should be able to get in and out of the driveway without physical contact with the ground.


I took some time gazing at the front of the car, and it hit me that the lower portion of the bumper had a bit of sag to it. It wasn’t terrible, but even an inch of droop makes a huge difference. There is a plastic belly pan that connects to the bottom of the bumper and it is there to provide a bit of support for the bumper. The belly pan on my car was in pretty bad shape, with cracks and various fasteners missing.

While a brand new replacement belly pan was an option, I honestly didn’t want to deal with the labyrinth of interconnected tabs and numerous missing fasteners I would have to locate to install it properly. So, I turned to the aftermarket for a solution.


I found a set of aluminum under body panels with all hardware necessary for the installation. This would provide the support and rigidity that the bottom of the bumper needed, along with providing a bit more ventilation than the original flimsy plastic belly pan.


With the new under body panels installed, the bumper sag was eliminated. I’m pleased to report that I no longer leave a streak of red paint on the driveway.

Parts Cost: $195.00

Total Spend: $346.79

Enjoying The Ride

Like I said in the beginning, I’m trying to drive this car more and more. I have finally built up trust with the machine. I have taken it on increasingly longer trips, I have stopped glancing at the gauges every second, and I have generally let my OCD fade away.


Old parts aftermath.

I recently participated in a regional Z car meet-up called Midwest Z Fest. It was multi-day event where Z car owners drove in from all over to just hang out. Owning a machine such as a 300ZX has allowed me to discover friendships I would not have found otherwise. Being able to converse with individuals who shared the same illness as me gave me a greater appreciation for life.

A sampling of Zs that turned out for Midwest Z Fest.


These people aren’t just car enthusiasts, they aren’t just Z car lovers, and some aren’t even just 300ZX Twin Turbo nuts. No, instead they are humans I can directly relate to. The stories, the feelings, and the scars we share are mutual. And that’s really cool.

For me, this Z is still very much a project. Not a project in the sense that I can’t drive it, but a project in the sense that I’m constantly chasing realistic perfection. There is a list of things I would like to improve on the car. Most are financially taxing, some are time intensive, and all are emotionally and physically draining. But, a project car is never truly finished, and honestly, I like it that way.


Peter Monshizadeh is the Practical Enthusiast. See more of his work here.