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VTI engine code P2178 and idle speed instability.

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10.02.2026 22:30 # 1
Kayzer89
Hello, my car is a 207 1.6 VTI and it's giving a P2178 rich mixture error. When I start the car, the idle speed increases, then the engine struggles for 5-10 seconds trying to regain its idle speed. The same problem occurs when I'm braking and about to stop; the idle speed drops and rises, making it seem like it's about to stall, and sometimes it does stall. I've cleaned the MAP sensor, the oxygen sensors, replaced both solenoid valves with original parts, and the air and oil filters are original. While driving, there are no problems; it performs quite well. I've also changed the transmission oil, but I haven't been able to find the problem. [https://static.cloudflareinsights.com/beacon.min.js/vcd15cbe7772f49c399c6a5babf22c1241717689176015] integrity="sha512-ZpsOmlRQV6y907TI0dKBHq9Md29nnaEIPlkf84rnaERnq6zvWvPUqr2ft8M1aS28oN72PdrCzSjY4U6VaAw1EQ==" data-cf-beacon="{"version":"2024.11.0","token":"11ac6a036a5c4b83a3c20a30a3bc3ba2","r":1,"server_timing":{"name":{"cfCache Status":true,"cfEdge":true,"cfExtPri":true,"cfL4":true,"cfOrigin":true,"cfSpeedBrain":true},"location_startswith":null}}" crossorigin="anonymous">
11.02.2026 00:45 # 2
Omer33
Swap the positions of the first and fourth coils. If it gives the same code, there's no problem with the coil, but if the code number changes, the problem is with the coil. Almost 10 years ago, I received a similar code and solved the problem with a coil, but I don't remember the code. https://static.cloudflareinsights.com/beacon.min.js/vcd15cbe7772f49c399c6a5babf22c1241717689176015" integrity="sha512-ZpsOmlRQV6y907TI0dKBHq9Md29nnaEIPlkf84rnaERnq6zvWvPUqr2ft8M1aS28oN72PdrCzSjY4U6VaAw1EQ==" data-cf-beacon="{"version":"2024.11.0","token":"11ac6a036a5c4b83a3c20a30a3bc3ba2","r":1,"server_timing":{"name":{"cfCache Status":true,"cfEdge":true,"cfExtPri":true,"cfL4":true,"cfOrigin":true,"cfSpeedBrain":true},"location_startswith":null}}" crossorigin="anonymous">
11.02.2026 15:41 # 3
Kayzer89
Could it be the canister valve? I haven't had the coils checked at all; my car only has 115,000 km on it. This problem didn't exist before the original diagnostics were reset, but it was consuming more fuel and was more lively. I started experiencing this idle problem when we reset the settings to normal. data-cf-beacon="{"version":"2024.11.0","token":"11ac6a036a5c4b83a3c20a30a3bc3ba2","r":1,"server_timing":{"name":{"cfCache Status":true,"cfEdge":true,"cfExtPri":true,"cfL4":true,"cfOrigin":true,"cfSpeedBrain":true},"location_startswith":null}}" crossorigin="anonymous">
11.02.2026 23:04 # 4
Omer33
When I first encountered this problem, the car had around 90,000 km on it. The code changed when the coil was repositioned, and then the problem was fixed when the faulty coil was replaced. I can't say anything about the canister valve. If you consider repositioning the coil, you'll have a chance to fix it without paying extra. I'm not a mechanic; I can only hold a screwdriver and pliers. https://static.cloudflareinsights.com/beacon.min.js/vcd15cbe7772f49c399c6a5babf22c1241717689176015" integrity="sha512-ZpsOmlRQV6y907TI0dKBHq9Md29nnaEIPlkf84rnaERnq6zvWvPUqr2ft8M1aS28oN72PdrCzSjY4U6VaAw1EQ==" data-cf-beacon="{"version":"2024.11.0","token":"11ac6a036a5c4b83a3c20a30a3bc3ba2","r":1,"server_timing":{"name":{"cfCache Status":true,"cfEdge":true,"cfExtPri":true,"cfL4":true,"cfOrigin":true,"cfSpeedBrain":true},"location_startswith":null}}" crossorigin="anonymous">
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