PO 174

New member here and a new 4Runner owner.

So, I bought a 2005 V-8 4.7 4Runner SR5 2WD with 157,000 miles. A few days afterwards it starts showing the check engine light along with the VSC/TC lights. I run the code and get PO174.

I replaced the air filter and MAF, nothing. Replaced the PCV and gas cap, nothing.

Took it to a shop I trust and they smoke tested it which showed it needed the PCV hose, intake manifold gasket set, fuel injector O-ring and fuel injector cushion ring-lower which were all changed and 10 miles later I am again getting PO171 & PO174.

ETA, the shop tested the fuel pressure and it was within spec.

The only thing I can guess is the O2 sensors?



Any ideas?

 

How does it run?

 

Find a better mechanic!

My 2005 with 150,000 miles runs like a top (new), and has never been worked on except for oil and filter every 4000 miles, 4 starters (replaced in my driveway for $60 to mechanic). Starters $100 at Amazon.com OK.

Original water pump, alternator, tranny (fluid and filter once at 105,000 miles at dealer), all original exhaust (this amazes me).

4runner has never thrown a "code" on the dash in 15 years.

Long life Coolant change D/F (10 quarts) in the driveway once at 100,000 miles by owner. I think 4runner holds 10 quarts of Zerex Asian coolant. https://www.valvoline.com/our-products/antifreeze-products/zerex-asian-vehicle-antifreeze-coolant