I love old cars. I like to collect them. It’s a sort of hobby/addiction. Anyway, even though I’m a mechanic and can fix cars at first cost, I still need to ask myself the question – “Is this old car worth repairing?”
How do you know if an old car is worth your time, effort, and dollars, or is an old car just a money pit, a ball-breaking disaster in the making?
Let’s walk the road together. On this page, you’ll find a short video outlining the four main areas I check before committing to a new old car, but I cover the subject in greater detail below the video.
I’ve bought and sold hundreds of cars over the years, and here I’ll cover my old car evaluation process in a little more detail. I’ll explain how to spot problems and a ballpark cost to repair them at a shop. But I’ll also indicate if these common repairs are something the DIY weekend mechanic can do themselves with little or no tools or knowledge.
Four Tests For A Golden Oldie
All old cars have issues. The trick is to sell an old car at the first sign of serious trouble or avoid buying someone’s problems, whichever side of the deal you’re on.
When checking out a vehicle, I pass them through four critical filters. The car must pass these tests to be considered a keeper. Failing a test means I’ll cut the inspection short, thank the owner politely, and continue my search in the classifieds.
So what are the four filters I use? We’ll cover them right now in greater detail.
One – Is Vehicle Corrosion Free?
This one is first because it will, for the most part, be obvious and may save you a lot of time. Corrosion is a car killer, and your first clue is where your potential new purchase lives, i.e., Is it a salt state? If it is, there’s a better than evens chance it could suffer from corrosion.
You may not even need to climb under the car. Rust blisters at the bottom of doors, fenders, and cills clearly indicate that the chassis is also affected by corrosion. Chassis corrosion is terrible news. While cosmetic rust on fenders and doors can be repaired, chassis corrosion is more serious. It’s expensive to fix and may compromise safety.
In addition, finding body corrosion means other mechanical components may also be affected, like brake lines, etc., which we’ll cover in the mechanical section below.
Corrosion hot spots to check include:
- Check bottom of doors, trunk floor, bottom of fenders, cills (especially jacking points) around body mouldings etc.
- Under hood, chassis legs, valances, cross members, battery tray etc.
- Using an led light and a screwdriver (ask permission first) have a poke around under the car; you won’t need to jack the car up. You’ll see and reach plenty from the sides, front, and rear of the car.
Finding surface corrosion is acceptable for old cars, but finding holes means this inspection is over.
Two – Has Vehicle a Full Service Record?
How a vehicle has been treated throughout its life makes a real difference to how reliable it will be in the future. If it’s been dogged thus far, no amount of pampering from now on will undo the damage. A vehicle that is visibly well cared for is a wonderful sign, and I’ll cover how to spot the subtle clues at the end of this section.
But for now, let’s look at the hard evidence – receipts and maintenance book dealer stamps. We’d ideally like to see a complete record of the following:
- Engine oil and filter changes
- Transmission oil and filter changes
- Major service (B) plugs, air filters brakes, etc
- Coolant changes every 3 – 4 years
- Brake fluid changes every 3 – 4 years
- Timing belt and water pump change (if belt driven)
- Aux belt replacement
- Aircon oil top-up and regas
- Coolant thermostat replacement
- Anual wheel alignment
- Tire replacement
If the repairs were carried out at the main dealer, you know the previous owner didn’t skimp on maintenance. Sure, there are plenty of pro-independent shops about. But I rather see a dealer stamp than a Jiffy Lube sticker, if you know what I mean.
Three – Are The Mechanicals Strong?
Checking the mechanicals intimidates many private buyers; they may not know their way around the mechanicals, and I understand.
So here’s a good tip for those that aren’t comfortable poking around under the hood – you are likely driving years and are very experienced in how a good car should perform. Use that knowledge on the test drive. Very often, the car itself will let you know something is amiss. Use your instinct.
I’ll cover what to look out for on the test drive below.
For those happy to poke around the mechanicals, here’s a list of the major items to check.
- Check oil level and quality – a coffee crema look to the oil cap underside indicates a possible head gasket issue
- Check transmission oil level and color – Use a clean kitchen towel, oil should appear reddish, not dark brown or black
- Check coolant level and color – A weak-looking color may indicate old weak coolant, low coolant could indicate a coolant leak or head gasket failure
- Check brake fluid – Low level could indicate worn pads, dark color indicates neglected maintenance
- Bounce each corner of the car and observe – The suspension should be quiet and should stop bouncing on the second bounce
- Check tire wear – Uneven wear indicates suspension and or alignment issues
- Check under the vehicle for fluid leaks – Oil and coolant are the most common
- Check the metal brake lines – Brake lines corrode, especially so in salt states
The test drive
The test drive is all about using our senses. We’ll be checking for the following:
- Unusual noises
- Heavy vibration
- Strange smells
- Looking at gauges
Before setting off on the test drive, we must pay close attention to the driver’s display. In particular, we’ll need to check the following warning lights and their performance with the ignition on and when the engine is running.
With ignition on, check the following lights come on:
- Airbag light
- Check engine light
- Oil light
- Battery light
With the engine running, be sure all these lights go out.
A test drive comes down to four questions:
- How does the engine perform?
- Does the transmission shift smoothly and timely, both up and down the gears?
- How does the vehicle handle bumps and corners?
- How does the vehicle stop?
If the answer to all of the above is positive, congrats, you’re likely looking at a good car.
Four – Is Electrical System in Great Shape?
Electrical issues are very common in older cars. Even older cars (10 years plus) are sophisticated, meaning they use a ton of sensors and computer modules to manage various systems, from something as simple as window control to more complex tasks like engine management.
Vehicles use multiple modules that communicate with each other on a network. While robust, the system is sensitive to changes in resistance since that’s how they communicate. The problem with older vehicle wiring is the wiring terminals often become loose, which increases resistance, and those crucial messages between modules are lost.
While it’s easy to explain the issue with wiring – “bad connection,” finding the exact point of failure is more complex and very time consuming, and that equals expensive repairs.
So it is important to check for electrical issues. They commonly come in two flavors – minor acceptable issues, and this is a deal-breaker.
The minor issues you may never fix, for example, a power roof that is closed but doesn’t work, aren’t a big deal, but headlights or signal lamps that don’t work are a significant issue. They’ll need immediate attention.
Your job is to check you don’t have that second flavor. And how do you do that? You start the vehicle and play with as many knobs and buttons as you can, seeing what works and what doesn’t. Pay special attention to the car heater controls, lights, signals, windows, and door locks.
Tell Tale Signs Of A Good Car
Here are some visual cues of a good car. Sure, they are obvious, but the obvious is often overlooked.
- Car parked in garage
- Clean car inside and out
- Owners yard/garage is orderly and clean
- Seat covers fitted
- Floor mats fitted
- Tons of repair receipts
- Service stickers under hood
- Cleaning materials in trunk
- Original jack, tire iron and tool kit in place
- Emergency kit in the trunk
Common Old Car Maintenance & Repairs
Here’s a table of old car common repairs and a ballpark repair shop estimate. The table also indicates if the repair is something a newbie could realistically do themselves. Repairs are in no particular order, and I’ve chosen a ten-year-old Toyota Camry with a 3.5 V6 donkey.
|Old Car Common Repairs||Repair Shop Supply & Fit $||DIY Difficulty Rank||Parts $|
|Starter replacement||328||Moderately difficult||75|
|Brake light switch replacement||193||Easy||42|
|Windshield washer pump replacement||178||Easy||25|
|Front Strut replacement (x2) (F)||1219||Moderately difficult||200|
|Power steering pump replacement||568||Difficult||158|
|Brake pads replacement (F)||210||Easy||27|
|Rotor replacement (F)||450||Moderately difficult||85|
|Clean throttle body||255||Easy||25|
|Throttle body replacement||455||Moderately difficult||165|
|Wheel speed sensor replacement (F)||418||Easy||38|
|Wheel bearing replacement (F)||246||Moderately difficult||52|
|EGR valve replacement||403||Moderately difficult|
|Heater blower replacement||336||Moderately difficult||78|
|Mass Airflow replacement||287||Easy||36|
|Oxygen sensor (upstream) replacement||607||Moderately difficult||55|
|Crankshaft sensor replacement||670||Moderately difficult||20|
|Wheel stud replacement||189||Moderately difficult||12|
|Brake caliper replacement||353||Moderately difficult||107|
|Master cylinder replacement||514||Difficult||97|
|Wiper motor replacement||302||Moderately difficult||150|
|Window regulator replacement||1141||Difficult||27|
|Radiator replacement||737||Moderately difficult||167|
|Rad hose replacement||150||Moderately difficult||12|
|Power door lock motor replacement||588||Moderately difficult||150|
|Rocker cover gasket replacement||110||Moderately difficult||16|
|Ignition coil replacement||301||Easy||22|
|VVT solenoid replacement||303||Easy||36|
|Fuel pump replacement||539||Moderately difficult||85|
|Horn replacement||180||Moderately difficult||21|
|Door mirror replacement||355||Moderately difficult||50|
|Drive axle (1)||435||Difficult||65|
As you can see, there is quite a difference between shop and DIY costs. DIY will save you a ton, but remember – you’ll need special tools and knowledge to attempt some of these repairs.
Here are a few inspection tools that won’t break the bank but will save you money.
The TopDon is an inexpensive fault code reader. This mighty little tool allows you to interrogate the car’s PCM and check for significant issues logged inside the car’s module. Check out the Topdon review I made earlier this year. The review covers its capabilities in more detail.
The Topdon battery tester will check battery health, perform a cranking test and test the alternator performance in seconds. It is inexpensive and uses the traffic light system to signal results. I tried and reviewed it earlier this year, and you can check it out here – “Best battery tester for home use.”
I can’t work without good light; if I don’t have good light, I find the job goes downhill quickly. Enter build these tough mechanics light; I’ve had several of these lamps, not because they break but because I lose them.
I’ve bounced mine on the ground so many times, and it survived. They are a real MacGyver of a lamp, magnet, hooks, led area light, and spotlight.
About the Author
John Cunningham is a Red Seal Qualified automotive technician with over twenty-five years of experience in the field. When he’s not writing about car repair, you’ll find him in his happy place – restoring classic cars
You may find the following links helpful:
- Beginner car maintenance page
- Car repair and troubleshooting index
- OBD fault code list
- Tools and parts page
- About the Author
- Latest Posts
John Cunningham is an Automotive Technician and writer on Rustyautos.com. He’s been a mechanic for over twenty-five years and has worked for GM, Volvo, Volkswagen, Land Rover, and Jaguar dealerships.
John uses his know-how and experience to write fluff-free articles that help fellow gearheads with all aspects of vehicle ownership, including maintenance, repair, and troubleshooting.