Toyota 4Runner Problem Report
Toyota 4Runner Check Engine Light With Code P0170
Occasionally, the mass air flow sensor can go lean and set a code P0170 for fuel system lean. This in not an oxygen sensor problem. If there are no vacuum leaks, the mass air flow sensor may need to be replaced. Our technicians remind us to use a factory part because the aftermarket rebuilds are very inconsistent.
P0170 code was showing when tested, chcked for vacuum leaks and found a cracked vacuum hose, replaced and code was gone. - Visitor
A toyota certified machanic has informed me I need to replace my mass air flow sensor on my 99...
When a mass air flow sensor problem occurs, resulting in a loss of power or hesitation on accel...
no problem just upgrading to a performance air sensor.
upgrading to a performance Jet Chip air sensor