A mobile mechanic named Simeon shared a story about a repeat customer who wanted to save money by buying her own spark plugs. The plan completely failed and led to several expensive repairs. Simeon posted about this on TikTok, where the video got over 130k views. He warned car owners that buying your own parts might seem like a good way to save money, but it usually ends up costing more.
According to Motor1, the problem started when the customer asked Simeon for a price quote to replace her spark plugs. The total cost was too high for her budget. She asked if she could buy the parts herself and just pay him to install them. Simeon was worried about this idea because spark plugs are not the same for every car. But he agreed because she was a regular customer.
Simeon gave her very clear instructions about what to buy. He told her to get NGK spark plugs because those work best in her specific car. He warned her that other brands might not work right and could damage other parts of the engine.
The AutoZone employee’s advice caused a chain reaction of failures
The customer went to AutoZone, but they didn’t have the NGK plugs Simeon told her to get. A store employee suggested she buy different plugs instead, and she listened to them. Simeon didn’t want to install these wrong plugs, but he did it anyway.
Only one or two weeks later, the check engine light came on again. Simeon checked the car and found it was misfiring multiple times. The wrong spark plugs were causing the problem. He told her they needed to replace them with the correct NGK plugs.
She agreed but asked for a discount on the new parts and labor. Simeon said no at first because he had warned her this could happen. But she kept asking, so he gave her the discount.
One week after installing the correct plugs, the check engine light turned on again. This time, the coil pack for cylinder three had completely stopped working. The customer immediately blamed Simeon for breaking it. He reminded her that he had warned her about these problems from the start. She agreed to buy the new coil pack but took her car to a different mechanic to fix it. She also sent Simeon a long text message telling him how to be a better mechanic.
Simeon realized his real mistake was agreeing to bend his rules in the first place. “The only thing that situation taught me was that there are policies and rules for a reason. If I had just stuck to my guns from the beginning and be like no, we don’t allow customers to purchase their parts. We purchase all parts for this exact reason. This would’ve never had been a problem in the first place,” he says.
Mechanics often encounter shocking discoveries during routine vehicle inspections that remind them why professional expertise matters.
People online had strong opinions about who was at fault. Many people were shocked that the woman trusted an AutoZone worker more than her own mechanic. One person said: “Your 100% right. Learned this lesson aswell. Trying to help someone out can turn around and bite you.”
However, some mechanics said Simeon was partly to blame, too. “My man should have not installed those plugs to begin with . This is 100 percent your fault my guy,” one person commented. Simeon agreed with this advice and admitted he should have stuck to his original judgment and refused the job. This isn’t the first time mechanics have dealt with unexpected problems found under the hood of customer vehicles.
Published: Dec 10, 2025 01:45 pm