Engine Management Light?

coco_lola

The engine management light came on in my Yaris the other day, so we put the OBD into it and it came up as "P0172 System Too Rich Bank 1" which could apparently be one of four things, including the air flow sensor and the oxygen sensor. My mechanic told me to keep driving it for the time being, as it is not currently detrimental to the engine, and that eventually a light will come on the dash to single out what's wrong.

I'm just wondering is there any other way of finding out? I wouldn't be handy with cars myself, I just know the basics to make sure my car is kept "healthy". The car is driving perfect at the moment, am not noticing any problems, but I assume it will affect it in the long run!

beam99

Possible causes

• Injector blockage
• Manifold absolute pressure sensor
• Engine coolant temperature sensor
• Fuel pressure
• Gas leakage from exhaust system
• Open or short in heated oxygen sensor (sensor 1) circuit
• Heated oxygen sensor (sensor 1)
• ECM

He should be able to narrow it down by looking at the fuel trims, and out puts of the o2 sensors.

coco_lola

well the coolant light comes on blue for the first five mins that I drive the car. would that be a possible reason?

hiluxman

coco_lola wrote: »

well the coolant light comes on blue for the first five mins that I drive the car. would that be a possible reason?

thats supposed to happen, its to tell ya the car is cold
ya could say to your mechanic to check the air flow meter, they give a bit of hastle

coco_lola

ok thanks, will try that. he said that it will drive ok and is not detrimental to the engine but Id rather just get to the root of it and fix whatever it is before it becomes a bigger job!! :eek:

johnayo

Just wondered if the mechanic did an exhaust gas analysis? because whilst it may not do any damage to the engine, it may damage the "cat" if it is running rich.

coco_lola

not quite sure what he did... he seems to have got to the root of the issue.. he thinks it may be a Lambda sensor?