P0171 and PO174

Curious as to what fixes have been taken on these two codes taking the truck to the dealership tomorrow to have fuel injectors cleaned. Already did new MAF sensor. Was told to replace both upstream sensors. No rough running code goes off and comes back.

 

Where did you get your previous MAF? Particularly import to go OEM on that one...

 

I did the denso OEM one. But code was showing on and off prior to doing that so just checking things off the list from what I have read on the code readings. As well as getting all maintenance up to date before the beginning of the year which I do every year.

 

You need to properly diagnose it or find someone that can properly diagnose it, lean codes aren't something you just throw parts at (really hardly any codes/issues are for that matter). First step aside from checking for obvious vacuum leaks is to look at fuel trim and AFR/O2 sensor data under various operating conditions to determine when it's running lean, how lean it's actually running, and if it's in fuel control or not. Then based on that data we can determine where/what to start testing.

I'd also like to know is the intake system stock?

 

I don't have a computer to diagnose that so I'm going to let my guy at toyota do that this morning. The truck does have a stock intake with a k&n filter in it which I don't see that being an issue but could be a factor but it's always had a k&n filter and I keep it cleaned and lightly oiled being we have the same air filters in all the boats we work on.

 

I also am gonna have them go ahead and replace the pcv and the hose on the truck being I haven't had that done since I've owned it.

 

So did you have the problem resolved? What did he find out?

 

A/F ratio sensors needed to be replaced fixed issue on the two codes. But went ahead and replaced pcv valve and as well did new spark plugs and had fuel injectors tested and cleaned.