Computer problem
1995 Chevy Caprice V8 Automatic 200000 miles
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I noticed my car started running bad and was losing power. I was told I needed a tune-up. My check engine light started coming on but I had a complete tune-up done shortly after. The light still comes on after the tune-up so I took it to a mechanic who said he fixed it. But it could be some sort of "egr valve making it come back on." After I left them by the time I made it to the corner it had come back on. It doesn't stay on, but every few miles it will come on and eventually gon back off. What could it be? I don't want to take it back without having an idea because you never know if someone is trying to swindle you.