Joe Mohammed isn't angry that the gas company failed to read his meter for almost 12 years. But he's steaming about the bill he got last Wednesday for $5,353.63, the one he got last Thursday for $5,353.63 and the one he got Friday for $5,217.17.

Mohammed owns Ernie's Bar & Grill, a bar in northwest Detroit that came equipped with two gas meters. The bar has two meters because two tenants occupied the building before it became Ernie's. Since 1969, when Mohammed bought Ernie's, the meter reader dutifully read one meter and told Mohammed not to worry about the other. Mohammed didn't. "Who am I to tell him how to do his job?" Mohammed said.

When the first bill from Michigan Consolidated Gas Co. arrived last week, Mohammed figured it was a result of computer error. His gas bills average $900 a month, he said, and he always pays on time. Instead he was told the bill was for his second account. "That was news to me," Mohammed said.

A gas company spokesman said the meter had not been read between 1970 and February 1981 because the meter reader had no computer card for the second meter at Ernie's.

Although the company was notified of a "missing reading," the problem was never corrected.

The gas company said it will recompute the bills and send an investigator to settle them. "We made some big mistakes, and we intend to correct them," a spokesman said.