Rough idle after changing purge valve

Demustang

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I’ve got a 2014 Ford Mustang V6 that idles rough after refueling and when the engine warms up after a cold start. Looked around the forums with the same problem but no luck.

It started when my car gave me CEL codes P2198 and P2196. I looked up the problem (which was a bad purge valve), went to buy a purge valve, installed it, and the codes went away.

But when I refill it with gas, the engine would start idle rough about a minute after starting. It sounds like the engine wants to shut off but the RPMs bounce back to normal idling every 5 seconds. This would go on for about 2 minutes and the rough idle fades away. This would be the same case when my car warms up after a cold start.

Things I've done:
•Bought another Purge Valve just in case the first part was defective (Which it wasn't).

•Adding fuel treatment after filling up.

•Disconnected the battery and reconnected it for battery relearn.

•Cleaned the Mass airflow sensor.

Worth mentioning:
•When the engine starts to sound like it would want to stall, the purge valve will stop making the ticking noise until the engine goes back it its idling RPMs.

•Occasionally, I would get a CEL code P0442 but would clear itself on it’s own.
 
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I’ve got a 2014 Ford Mustang V6 that idles rough after refueling and when the engine warms up after a cold start. Looked around the forums with the same problem but no luck.

It started when my car gave me CEL codes P2198 and P2196. I looked up the problem (which was a bad purge valve), went to buy a purge valve, installed it, and the codes went away.

But when I refill it with gas, the engine would start idle rough about a minute after starting. It sounds like the engine wants to shut off but the RPMs bounce back to normal idling every 5 seconds. This would go on for about 2 minutes and the rough idle fades away. This would be the same case when my car warms up after a cold start.

Things I've done:
•Bought another Purge Valve just in case the first part was defective (Which it wasn't).

•Adding fuel treatment after filling up.

•Disconnected the battery and reconnected it for battery relearn.

•Cleaned the Mass airflow sensor.

Worth mentioning:
•When the engine starts to sound like it would want to stall, the purge valve will stop making the ticking noise until the engine goes back it its idling RPMs.

•Occasionally, I would get a CEL code P0442 but would clear itself on it’s own.
It sounds like the symptoms of overfilling the gas tank. Never round out the cents after the nozzle clicks off. It fills your charcoal canister with gasoline and causes all sorts of problems including rough idle.

https://www.autotrader.com/car-shop...s tank can,failure, and cause solenoid damage.
 
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Sorry for the late reply. I do not continue refueling a bit more after the nozzle clicks.
There is something about fill ups that trigger it so what else can it be? The symptoms sound like you are flooding your canister including the purge valve codes. Do you fully insert the nozzle when fueling?
 

86GT351

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I’ve got a 2014 Ford Mustang V6 that idles rough after refueling and when the engine warms up after a cold start. Looked around the forums with the same problem but no luck.

It started when my car gave me CEL codes P2198 and P2196. I looked up the problem (which was a bad purge valve), went to buy a purge valve, installed it, and the codes went away.

But when I refill it with gas, the engine would start idle rough about a minute after starting. It sounds like the engine wants to shut off but the RPMs bounce back to normal idling every 5 seconds. This would go on for about 2 minutes and the rough idle fades away. This would be the same case when my car warms up after a cold start.

Things I've done:
•Bought another Purge Valve just in case the first part was defective (Which it wasn't).

•Adding fuel treatment after filling up.

•Disconnected the battery and reconnected it for battery relearn.

•Cleaned the Mass airflow sensor.

Worth mentioning:
•When the engine starts to sound like it would want to stall, the purge valve will stop making the ticking noise until the engine goes back it its idling RPMs.

•Occasionally, I would get a CEL code P0442 but would clear itself on it’s own.

P0442 is a small evaporative emission leak. Did you use a Ford part or aftermarket? Sometimes makes a difference.

A P0442 code is a diagnostic trouble code (DTC) that indicates a small leak in your vehicle's evaporative emission control system (EVAP). The EVAP system prevents fuel vapors from escaping into the atmosphere by trapping them in a charcoal canister until the engine can burn them. When the engine control unit (ECU) detects a leak, it triggers the P0442 code and turns on the check engine light.
 

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