Having problems with my inlaws 95 Taurus with the 3.8. Over the past few days the CEL has been coming on and off, it was running ok except for rough idle until today it started running like crap all the time. Took it to a garage, they checked the codes , showed oxygen sensors, one bank was lean and one was rich. They cleaned the MAF, replaced a leaky vacuum hose and replaced one of the oxygen sensors that had cracked porclan.
Then it seemed to run ok, the mechcanic even drove it for about 5 miles, ran good and no more CEL, so I thought great problem solved. As I left the garage I see the fuel light is on so I stop for gas, then about 1 mile down the road after getting gas the stupid CEL comes on again!!! So I turn around and head back to the garage, it seems to be running ok but the CEL stays on. The mechanic checks the codes again, shows oxygen sensors again but this time both banks are rich. He spent quite some checking things over but could find no other problems. Only thing he could think of was since I had just got gas, maybe got some water or something in the gas . So he added some Sea Foam to the gas, then say to drive it for a couple days and see if that helps.
I would appreciate any help with this, thanks!