I have a 97 chevy blazer, the service engine soon light has been on for a while now. I already identified the problem as the mass air flow sensor. Not having the money to replace the sensor, I have let the light remain on. When I fired it up this morning, it decided to have a hard time starting and when it did start, the idle was really rough to the point of almost dying. Then the light started flashing, which it has never done before. The whole truck was shaking from the rough idle, so I turned the truck off. One other problem it has been having is the fuel gauge goes haywire after the truck is on for a few minutes and shortly after, stops working all together. Any advice would be nice as I would like to minimize cost and damage to the truck.

 

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How to: MAF Sensor Cleaning - DISCUSSION THREAD

The flashing light means a serious misfire condition.