A few weeks ago I started noticing a weird intermittent stalling in my 2015 Ford Focus during stops at traffic lights, and it really had me worried. Every few stops, the engine would sputter and hesitate before kicking back in. At first glance, I thought it might be a serious issue like a failing alternator or even a sensor gone haywire—and honestly, I was ready to shell out for a big repair bill.

Every time it happened, the Check Engine Light would flash briefly, but no clear warning code would stick. I immediately took it to my regular shop, and they initially assumed it was an electrical gremlin related to the battery or charging system. They even recommended some tests that were a bit over my head, and I left the shop still scratching my head.

Not one to let things slide, I decided to do some investigating myself over the weekend. I snagged an inexpensive OBD-II scanner online and started pulling codes when the problem reoccurred. Even though it wasn’t showing a persistent code, I did catch a momentary P0300—the generic misfire code—and P0455 for a very intermittent evaporative emissions leak. Both didn’t really add up to match the stalling behavior exactly.

After some online digging and watching a few YouTube videos from fellow Ford Focus owners with similar intermittent stalling issues, I found several posts hinting that a corroded connection on the fuel pump relay could cause symptoms just like mine. I inspected the relay and, lo and behold, discovered a bit of corrosion on one of the terminals. It wasn’t the “catastrophic engine failure” I’d feared—it was a simple electrical connection issue that was interrupting the fuel pump’s power supply at crucial moments.

Armed with this new theory, I carefully cleaned the relay terminals with some electrical contact cleaner and even lightly sanded them to remove corrosion. I reassembled everything, and after a couple of test drives around the neighborhood, the stalling problem completely disappeared.

The lesson here? Don’t always jump to the worst-case scenario when something odd happens with your car. Sometimes a little DIY troubleshooting and a bit of research can save you from a lot of unnecessary expense. If you’re experiencing similar intermittent issues—especially with stalling or misfires—check out those relay connections before you commit to more invasive repairs. Also, investing in a reliable OBD-II scanner and learning how to use it can be a real car owner’s best friend. Happy troubleshooting, everyone!