Vehicle present miles 51,000. CEL started coming on about 3 yr. ago at about 45,000 mi. Car runs perfect and gets 25 MPG highway. I purchased a scan tool to be able to reset the light myself and maybe find the problem. The only code I get is P0170 fuel trim bank 1. I have had 3 CELs come on since my scanner purchase. The STFT B1 was -3.%, -1.5%, 0.0% with the LTFT 32.0% in each case. Is the negative readings for the STFT causing the problem, and if so,what needs to be replaced and where is the location?
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