EVAC System or something else?

[scandy]

Hi all,

Hope someone has had this - I have a GS430 sport Mk2 and recently after refueling after a little while the check engine light comes on, had it checked and no codes. Disconnecting the Battery for about a minute clears it and it's fine for sometimes a week or two or until you fill up again and then it can be a week before the light comes on again. Also replaced the petrol cap with an OEM part as I noticed when I take the petrol cap off the 'whoosh' sound is now gone but the new petrol cap did not restore the pressure as it used to be so no change. No idling issues, MPG still 30 odd on a long motorway run so not using any more fuel and starts perfectly. Suspect the EVAC system but can live with it as would cost more than the car is worth probably to get to the bottom of it. Anyone had this in case it's a simple fix?

Thanks in advance.

[ColinBarber]

Ideally you need the error code. The engine light cannot come on without an associated fault code - I suspect whatever tool was used couldn't read all codes correctly/legacy OBD protocol.

It could be a leak in the fuel system somewhere, e.g. the charcoal canister, but it could also just be the pressure sensor itself that is faulty or the VSV - the correct fault code would help narrow down the issue:

[scandy]

Thanks for the info