How to Use AI as Your Personal, Cost-Free Mechanic

Owning a car is expensive enough. Add in poor mechanical diagnostics, and you’re not just paying for parts—you’re paying for guesswork. I’ve personally been through situations where mechanics couldn’t even detect a blown head gasket, despite clear symptoms like loss of compression, moisture buildup under the oil cap. The result? Wasted money, time, and frustration, all for zero results. All the money spent on diagnostics could have been used to fix the actual problem in my case for rebuilding the engine.

But now, there's a smarter, cost-free way to approach basic car diagnostics: AI. Tools like ChatGPT, Claude, Google Gemini, and other AI assistants can help you think through symptoms, rule out causes, and even generate checklists to discuss with mechanics—before you open your wallet.

My Experience: Misdiagnosed and Wasted

I have an aging 4WD with high mileage. One day, while driving to the Gold Coast, the thermostat suddenly showed the engine temperature skyrocketing. The engine was clearly overheating. When I popped the hood, I saw coolant in the reservoir boiling and overflowing—splashed everywhere. I was also rapidly losing coolant.

I took the car to a mechanic, who couldn’t identify the issue but still charged me a few hundred dollars for general servicing. The problem remained. Hoping for better luck, I brought it to another mechanic, who still couldn't pinpoint the cause. He replaced the radiator cap, thinking it might be the culprit. It wasn’t.

I wasn’t ready to give up on the car, though any sane person probably would have. So I went to the dealership, thinking their team would surely know better. They didn’t. They charged me around two thousand dollars to replace old coolant hoses and the radiator—possibly damaged by a previous mechanic. To be fair, after replacing the radiator, things improved slightly. I wasn’t losing coolant as quickly. But I still had to carry a bottle of coolant everywhere and top off the reservoir regularly.

You might think that was the end of it—but things went from bad to worse. One day, the car suddenly lost power. The engine started shaking violently, and no matter how hard I pressed the accelerator, it wouldn’t respond properly.

Regrettably, I took it back to the dealership. One of their staff went on a test drive with me to feel how underpowered the car had become. Their mechanic inspected it, scratched his head, and said they needed to perform a compression test, a fuel injection test, and other diagnostics—which came at a steep cost. They suspected a fuel injection problem. I paid around another thousand dollars for those tests. The result? A vague diagnosis stating that one of the cylinders wasn’t producing enough power.

They then told me a second-hand engine would cost around $25,000—not including labor. At that point, the car was essentially worthless. I couldn’t even sell it, except maybe to a dealer, and the car wasn’t worth nearly as much as I had already spent on it.

To keep the car, I considered buying a used engine from eBay or a wrecker for much less than the dealership’s quote. But could I trust an unknown engine with no clear history? Later, I learned that engine rebuilding was another option. However, people warned me that rebuilding can be more expensive than replacement and not always worthwhile.

What should I do? Unfortunately, ChatGPT wasn’t available at the time. I did a lot of Googling and research. Eventually, I realized the symptoms pointed to a blown head gasket—causing low compression and loss of power. Coolant had entered the engine, and when the engine ran, white smoke came out of the exhaust.

Later, I met a new friend who recommended a trusted mechanic. I took the car to him. He opened the engine cap, inspected the internals, and immediately suspected water in the engine. He told me to come back later for more testing. Eventually, he confirmed the diagnosis and offered to rebuild the engine for a surprisingly reasonable price—less than I had expected. However, there was a wait. I had to book months in advance because the engineer he worked with had a huge backlog. He needed to X-ray the engine block to ensure there were no cracks.

My experience with the car had been anything but smooth. A few months later, I finally got the car back. Even after the rebuild, the engine had misfires. The mechanic asked me to return in a week so he could investigate further. Luckily, the engine itself was fine. He just needed to reprogram the ECU (car computer). After that, the car ran perfectly again.

I was thrilled to have my car back in good condition. But the entire experience taught me a valuable lesson: correct diagnosis is everything, and you can’t always rely on mechanics to get it right.

But my story didn’t end there. A year later, I took the car in for a routine service. The mechanic told me everything was generally fine, but some parts needed replacing. He also advised that I take the car to a specialized shop to replace the steering rack, which would be cheaper there. I followed his advice and got it done.

A few days later, I started hearing a faint noise when turning—not loud, but definitely noticeable. I didn’t feel good about it and wasn’t sure if I should call the shop again. Then I had an idea: why not ask ChatGPT?

I’d been using AI tools since they became popular—for writing, coding, and even image generation—but I’d never used them for mechanical diagnostics.

From that point on, I decided to research more deeply and talk to AI systems like ChatGPT to help me understand car symptoms. The responses were surprisingly accurate, detailed, and useful.

AI Diagnosing Steering Noise After Rack Replacement

Main Symptom: Screeching Noise

Here was my prompt to ChatGPT:

My car replaced the steering rack, but started to make screeching noise while turning, is it normal

ChatGPT: No, it is not normal for your car to make a screeching noise while turning after replacing the steering rack. This could indicate one of several issues, such as:

• Low Power Steering Fluid – Air might have entered the system or it wasn't properly refilled and bled after the rack replacement.

• Improperly Installed or Loose Belt – If the power steering uses a belt-driven pump, a loose or worn belt can cause screeching.

• Misaligned Steering Components – If parts weren’t aligned correctly during reassembly, it can lead to abnormal noises.

• Pump Issues – The power steering pump might have been strained or damaged during the rack replacement.

• Dry or Unlubricated Joints – Some steering components may need lubrication and could squeak if dry.

It's best to have the mechanic recheck the installation to avoid further damage. Did the noise start immediately after the replacement, or did it develop gradually?

Me:

Gradually, I think

ChatGPT: Since the screeching noise developed gradually after the steering rack replacement, it's likely related to power steering fluid issues (e.g., low fluid or air trapped in the system) or a loosening belt that drives the power steering pump.

Here’s what you can do:

*. Check the power steering fluid level – Make sure it’s at the proper level and not foamy or discolored (which can indicate air or contamination).

*. Inspect the drive belt – See if it’s worn, loose, or slipping, especially when turning the wheel.

*. Listen closely to where the noise comes from – If it’s near the pump or belt, that narrows it down.

If you're not comfortable checking these yourself, it’s wise to return to the mechanic who did the work and explain the gradual onset of the noise. It may just need a fluid top-up and proper bleeding.

Would you like a checklist you can bring to the mechanic to describe the problem clearly?

Me:

I checked again, actually there were some noises when turning, but I can't say that is screeching

ChatGPT: Since the screeching noise developed gradually after the steering rack replacement, it's likely related to power steering fluid issues (e.g., low fluid or air trapped in the system) or a loosening belt that drives the power steering pump.

Here’s what you can do:

• Check the power steering fluid level – Make sure it’s at the proper level and not foamy or discolored (which can indicate air or contamination).

• Inspect the drive belt – See if it’s worn, loose, or slipping, especially when turning the wheel.

• Listen closely to where the noise comes from – If it’s near the pump or belt, that narrows it down.

If you're not comfortable checking these yourself, it’s wise to return to the mechanic who did the work and explain the gradual onset of the noise. It may just need a fluid top-up and proper bleeding.

Would you like a checklist you can bring to the mechanic to describe the problem clearly?

Me:

a bit like wind blowing

ChatGPT: Thanks—that’s a very helpful description. If the noise sounds like wind blowing when turning, it's likely a power steering-related whine. This often happens due to:

1. Air trapped in the power steering system – Common after replacing the steering rack if the system wasn't properly bled.

2. Low or degraded power steering fluid – Can cause a faint whining or "windy" sound as the pump struggles to circulate it.

3. Power steering pump wear – If the pump was already aging, the new rack could put added strain on it.

What You Can Do:

• Check fluid level – Make sure it's between the min and max marks. If it’s low, top it up with the correct type for your car.

• Inspect fluid quality – If it’s foamy or milky, that’s air in the system. A mechanic can bleed it properly.

• Turn the wheel lock-to-lock (fully left to right, a few times) while the engine is running, to help purge air—only if fluid level is good.

If the sound persists after doing this, it’s worth having the shop recheck the bleed and fluid or inspect for a potential issue with the pump.

Would you like help finding the right fluid type or a quick guide on how to check and top up the power steering fluid?

Another Symptom: "Chick Chick" Sound During Acceleration

Other than the steering noise, I also had a "chick chick" sound when accelerating. I asked ChatGPT about it:

When I accelerate, I can hear some tiny chick chick sound, what do you think that would be

ChatGPT: A faint “chick chick” sound during acceleration could be caused by a few different things, depending on the location and rhythm of the sound. Here are some common possibilities:

1. CV Joint or Axle Issue If the sound changes with speed and especially when turning or accelerating from a stop, it could be a worn CV joint or axle.

Check if the sound is louder when turning—this would point more directly to a CV joint.

2. Loose Heat Shield or Exhaust Component A loose metal shield near the exhaust can rattle or tick lightly during acceleration when vibrations increase.

3. Spark Plug or Engine Misfire (less likely if it’s very faint) Sometimes a tiny ticking sound can be from the ignition system—such as spark plug arcing—but this is usually more noticeable and may come with poor engine performance.

4. Belt or Pulley A worn serpentine belt or a slightly loose pulley can make clicking/ticking noises, especially under load.

5. Plastic Splash Guard or Trim Contact Occasionally, plastic underbody panels or fender liners can flap or tick against a moving part if loose.

To help pinpoint it better:

• Is the sound from the engine bay, wheels, or underneath?

• Does it change with RPM, speed, or only when pressing the gas?

Would you like a short checklist you can use while test-driving to help identify where it’s coming from?

Actions

Based on ChatGPT’s diagnosis, everything seemed to point to the newly replaced steering rack. So I decided to check the power steering fluid level first—and it was low. I topped it up and drove around for a while, making plenty of full lock-to-lock turns. However, the noise didn’t go away. When I checked the fluid level again, I was surprised to see it had dropped once more. I quickly looked under the car and noticed a small puddle of leaking oil.

I took the car back to the mechanic, who inspected it and found that power steering fluid was pouring out. He did a quick check, tightened a pipe or some component (I’m not entirely sure what it was), and that solved the problem. The noise disappeared, and even the light “chink chink” sound I used to hear during acceleration was gone.

ChatGPT was right!!!

Final Thoughts

AI doesn’t replace a qualified mechanic—but it empowers you as a car owner. It gives you confidence, saves you time, and helps protect your wallet from guesswork.

Next time your car acts up, try this:

1. Describe the issue to ChatGPT or another AI assistant.
2. Read the explanations carefully and follow suggestions.
3. Check what you can safely yourself.
4. Go to a mechanic with clarity and confidence.

You might be surprised how far AI can take you—before you ever lift the hood or reach for your credit card.