What causes a check engine light on my 2003 Toyota Tacoma sr5
Many, Many different things. Best bet is to have the truck scanned for the codes and you can know what to look for as the culprit.
could be alot of different things bring it to napa or orielies parts store they will scan it for free and let you know what you need to do. Do not know where you live but alot more parts stores are offering that service for free
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