Code result
P0170
Fuel Trim Malfunction
Moderate severity
What it means
The ECU detects that short-term and long-term fuel trim values on bank 1 are outside acceptable limits. Engine cannot maintain stoichiometric mixture — typically a vacuum leak, fuel pressure issue, or failing MAF/O2 sensor.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Vacuum leak (intake gasket, hose, PCV)
highOne of the most commonly reported causes for this code — check this first.
Fuel pressure too low or too high
mediumA plausible cause — test and verify before replacing parts.
MAF sensor reading drifted
mediumA plausible cause — test and verify before replacing parts.
Related help
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