P0172 Honda Accord EX CEL

[mosaud1998]

Well, first I got a CEL on the BMW for a bad catalytic converter (covered under the BMW warranty) and now the Accord gets one. Went to Autozone and they recommended the fuel injector to be replaced? Might need to throw in some Fuel injector cleaner to see if that may help. Any help would be greatly appreciated! Before I take it to a mechanic. Would it be safe to drive to work?

 

[Nukeman7]

Before you do anything, clear the code and see if it returns. If it comes back a second time, see the video below for typical solutions. And yes, it is safe to drive for now as long as it does not start missing on a cylinder.

 

[mosaud1998]

Before you do anything, clear the code and see if it returns. If it comes back a second time, see the video below for typical solutions.

Autozone cleared the code. I will see if it comes back. If it does, I'll try some Techron fuel injector cleaner and see if that works. If not, I'll watch the video and go through the steps

 

[Nukeman7]

Autozone cleared the code. I will see if it comes back. If it does, I'll try some Techron fuel injector cleaner and see if that works. If not, I'll watch the video and go through the steps

Techron is OK; however, I have had better results with RedLine SL-1 which is available at O'Reilly Auto Parts and on Amazon.

 

[Soft Cars]

P0172 Fuel System Too Rich Bank 1​

Not necessarily a fuel injector fault. Could be an issue with the MAF sensor.

I'd park the car and not drive it if it were me. You might be putting the catalytic converter at risk by driving the car.

 

[BAJA_05]

I would run back to back tanks full of Techron Complete Fuel System Cleaner or Regane High Mileage Fuel System Cleaner.

 

[mattd]

Heavily Fuel diluted engine oil can also cause this code

 

[mosaud1998]

Heavily Fuel diluted engine oil can also cause this code

How would that happen?

 

[RitcheyRch]

How would that happen?

Injector stuck open

 

[mosaud1998]

Injector stuck open

I opened the oil cap, doesn't smell like that oil is diluted with gas at all.

 

[The Critic]

Run the Cylinder AF test, may find that it needs injectors.

 

[SC Maintenance]

P0172 is system too rich bank 1. It means your primary A/F sensor is sensing a rich mixture. Your fuel trims are I believe now over -25% to throw that code.

Autozone should have grabbed the freeze frames before they cleared everything - why I encourage people to own and learn to use an OBD scanner even if they don't do their own work.

It could be a single fuel injector - but I that would be low on my list. I assume this is a 4 cylinder. If a single injector sticks - unless its wide open, the ECU won't know this and will simply lean out the pulse width - making 3 cylinders run really lean, and one cylinder still rich. You might at that point end up with other codes - maybe a misfire.

My guess is also either MAF (clean it to start). Can also be your primary A/F sensor - aka 02 sensor. The good news is too rich is likely not a vacuum leak.

I agree with @Soft Cars - don't drive it - possible to ruin your cats.

 

[mosaud1998]

I just had Dad put some techron fuel injector cleaner in it today before filling the tank up. He doesn't really want to drive either of the other cars to work. So, I can't really tell him not to drive the car. It's due for plugs so I think I'll be doing plugs next week. NGK it is.

If the CEL comes on again, I'll scan it with the BMW scanner I have. I think I'll be able to scan CEL codes.