Code 0172

Hey everyone. I have a 2002 Prerunner. I have a code 0172. It's been to two mechanics and replaced many parts and the code will not go away.....can someone please help me.

 

What did they change?

https://www.tacomaworld.com/threads/p0172-code.744847/

 

Plugs, wires, egr valve, map sensor, ignitors, O2 sensor (3), cat, fuel injectors, all vacuum lines and a few other parts.

 

Welcome to TW! If you post in the 1st Gen section you might get more responses.

 

What engine?.

2.7 or 3.4?

 

3.4

 

Do you have a scan tool?

If so what are your Long Term and Short Term Fuel Trims?

 

Actually, if you have a scan tool.
We need to know fuel trims, coolant Temp, and A/F sensor voltage with engine warm and idling.
That would help us a lot.

 

Welcome to TW..

 

This is way above my expertise. Can you please tell what to do. I'll buy a scan tool tomorrow. Where in the tool can I find this info.

 

It may be a little advanced for you then.
In the end, you'll likely need to graph A/F sensor data.

Anyways, what I asked for above would be under the live data section on the scanner.
Honestly, you need to find a "good" shop. Don't let anyone else blindly throw parts at it.
Make them guarantee their work.

 

Welcome a similar experience years ago at a local Toyota dealership cost me $2400 over 3 weeks and the problem still persisted for a $40 part (my mistake). NONE of what was replaced needed to be touched. Don't give them a second chance to make a first impression. You can't trust what they say because you've seen what they do. I've always ordered parts from the dealership, but have (2) master mechanics who only work on Toyotas to do whatever is needed on my truck. Find someone who knows their shit with whom you've established trust and you'll be much better off. This site provides solid resources (people / info) to keep you on course with your truck.