97 altima exhaust problems

Hi. I've got a 1997 Altima that has suddenly become a problem. About three weeks ago, the service engine light came on, so I took it to the garage to
have it checked. They said the code was for the mass air flow sensor. They also said there was a problem with the exhaust system. The charge for replacing the maf sensor was $600 and they wanted another $500 to fix the exhaust. I asked if having the maf sensor replaced and waiting a month or so on the exhaust system would hurt anything. They said no, so I had the maf sensor replaced but nothing was done about the exhaust. Now, three weeks later the service engine light is back on and they are saying I need a new egr valve and egr sensor. Are all of these things related? How much should I expect the egr valve and sensor replacements and work to cost? Would fixing the exhaust solve all these problems? I hope someone can help me out. I'm waiting until Monday to tell them what to do. Thanks in advance.
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The EGR valve and EGR sensor are exhaust related. But, why don't you go and purchase a code reader and validate the problem yourself. No, a MAF would not cause the other two items to go out. But, I would want to have the codes myself to make sure of the problems.
bluedog05 wrote:

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