My check fuel cap light stays on now and the cap is tight. Not sure why can anyone help?
Check Fuel Cap light
- Thread starter Vinny575hp
- Start date
is the cap new?
Just because the cap is tight doesn't mean that it doesn't have an air leak
Just because the cap is tight doesn't mean that it doesn't have an air leak
It's not the stock one but I'm not sure how old it was before I put it on. I might just buy a new one. Could that also cause bad mpg?
Absolutely. I'd get a motorcraft one. Local dealer should have one.
Motorcraft # FC-91
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The proper way to diagnose this would be to put the evap system into a test mode and observe the evap pressure system and how much it drops and loses or climbs from vacuum during this procedure.
OP, have you run a scan test for any codes? My guess would be a PO455 code, which is a large leak and suggest that the cap was not secured properly. However, if the cap has been secured properly my guess would be that the vapor management valve is not functioning as designed.
Check for codes and let us know.
OP, have you run a scan test for any codes? My guess would be a PO455 code, which is a large leak and suggest that the cap was not secured properly. However, if the cap has been secured properly my guess would be that the vapor management valve is not functioning as designed.
Check for codes and let us know.
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