If you use an obd reader to to delete the check engine light for a problem which hasnt been fixed, the check engine light will eventually come back on. My question is, regarding the code that is on memory, will that also go when you delete the code and come back on later for an unfixed problem or will it always be present until the problem is fixed?
Put it another way, let's say you are buying a car, if the seller deletes all codes just before the buyer arrives, will the buyers obd reader not see the codes?
Or if the buyer puts his obd reader in, will this reveal all the codes(i.e. they are permenantly there until fixed and deleted and its only the check engine light that temporarily goes)?