I have a 08 Mustang GT, when its cold no issue .as it warms up it wont take gas, and idles real choppy in the 300-500 rpm range, I get no codes on anything, I have replaced the fuel pump and filter, cleaned the MAF, and T/B, replaced the throttle position sensor Fuel pressure sensor,throttle motor does work when its not running, I have tried the stock tune still no difference,plugs have been replaced 850 miles ago, Its not the gas filled other car at same place 1/2 after later and its fine
My car has 10210 miles.
My car has an automatic transmission.
Hi there. It looks like you have inspected most of the common culprits of a choppy running engine. However, when the vehicle gets hot and has running issues, it's commonly caused by the EGR valve or EGR valve temperature solenoid. As the engine gets warm, the exhaust gas recirculation valve can become stuck, leading to an lean engine condition, which typically lowers the RPM as you've indicated. Check this component, clean it, and see if that clears up your problems. If not, feel free to contact one of our professional mechanics to see if they can inspect the choppy engine issue and find the source of the problem.
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