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'87 check engine light problems

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Old Aug 8, 2010 | 07:29 PM
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Default '87 check engine light problems

I bought my '87 Corvette in May. The check engine light comes on when I am driving. My mechanic checked it with a scan tool. The code comes up with the mass air flow sensor (code 34) and the o2 sensor (code 44). The guy I bought it from told me he replaced the mass air flow sensor, the o2 sensor and the ECM to fix the problem. It did not work. So he did a propane test for leaks and it checked out okay. My mechanic thinks it is a wiring problem because the problem is intermittent. Some days it runs perfect at idle/low speeds and highway speeds. Other days it idles rough and misses on acceleration. When you take off from a stop light it also has a "flat spot" before it accelerates. When cruising on the highway I am getting 21 to 23 mpg.
The engine/car has 75,000 miles on it with no modifications. I am the third owner. The previous owners were old guys like me who took immaculate care of this car. Any suggestions will be greatly appreciated before I start dumping money into this car to fix the problem.
Thanks.
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Old Aug 8, 2010 | 09:13 PM
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From: Database Error Indiana
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I'd replace both relays for the MAF. That should fix the MAF code. Then replace the O2 again. If the MAF is making it run rich, that can foul the O2 sensor. They foul, similar to a spark plug and then give bogus readings.
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