Stinger
forum member
So my Mustang went from running great (Lito tune) to running super rich last weekend. Parked it in the garage running great, got in it the next day and it started, did the 5 second idle up and as it settled down to the ~1000 rpm idle it stumbled and died. Restarted it and same thing. Restarted it again, gave it some throttle to rev it up and as soon as I let off the throttle, it died again.
So I stopped and scanned for codes and there were no codes (which is weird). So I determined it's running super rich (smells like gas, burns eyes if you go behind the car right after revving it up, condensation that blows out of exhaust smells like gas).
I recorded a few datalogs and sent them to Lito to see if he could spot anything but we didn't make any progress.
It runs PERFECT during the initial startup and the 5 seconds after it starts which should eliminate any mechanical issues.
Here is a video of multiple startup attempts. First couple I don't give it any throttle, just let it do it's thing. After that I start screwing with the throttle to keep it running/rev it up and clear out the excess fuel.
https://www.youtube.com/watch?v=IjoHqdl4MtE
At 46 seconds into the video the ECU resets after the car shuts off (you can here it beep and says engine temp warning and check fuel cap in the cluster).
Just after 1 min mark of video you'll see it drops below 300 rpm and then back up to 1000 rpm a few times, that's not me giving it throttle, it's just nearly stalling and then catching it self momentarily before going back to running rich.
With no codes and apparently no mechanical issues, I don't even know where to start with diagnosis. Anybody ever had similar issues? Thanks.
So I stopped and scanned for codes and there were no codes (which is weird). So I determined it's running super rich (smells like gas, burns eyes if you go behind the car right after revving it up, condensation that blows out of exhaust smells like gas).
I recorded a few datalogs and sent them to Lito to see if he could spot anything but we didn't make any progress.
It runs PERFECT during the initial startup and the 5 seconds after it starts which should eliminate any mechanical issues.
Here is a video of multiple startup attempts. First couple I don't give it any throttle, just let it do it's thing. After that I start screwing with the throttle to keep it running/rev it up and clear out the excess fuel.
https://www.youtube.com/watch?v=IjoHqdl4MtE
At 46 seconds into the video the ECU resets after the car shuts off (you can here it beep and says engine temp warning and check fuel cap in the cluster).
Just after 1 min mark of video you'll see it drops below 300 rpm and then back up to 1000 rpm a few times, that's not me giving it throttle, it's just nearly stalling and then catching it self momentarily before going back to running rich.
With no codes and apparently no mechanical issues, I don't even know where to start with diagnosis. Anybody ever had similar issues? Thanks.
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