System too lean? - Toyota Nation Forum : Toyota Car and Truck Forums

RXTech · 05-11-2005, 12:21 AM

My 2000 Corolla VE is throwing the code po171. My mechanic says that means that my system is running too lean and I need to take it to a Toyota dealer to have that problem corrected. Can someone explain in terms a girl can understand what "running too lean means"? Is this an expensive problem to fix?

Thanks Ya'll!

Dr Tweak · 05-11-2005, 12:25 AM

Okay, step one, get a new mechanic. Step two, a lean condition means that your engine is not getting enough fuel. It's possible that the 02 sensor(s) are bad. Or there could be a crack in your exhaust near the sensor that's causing it to give false readings.

Or, if it's not a sensor problem and your engine really is running lean, you can confirm that by taking out the spark plugs and looking at them. If they're white that generally means the engine is lean. Possible causes are a clogged fuel filter, fuel pump that's starting to go, or clogged injectors even. And if it's not that, it could even be any one of the sensors that tells the computer how much air is going into the engine, which being that your Corolla is a 2000, it would be the MAF.

Cleaning the MAF could help too.

I hope that helps!

5Sfte · 05-11-2005, 12:26 AM

The term too lean refers to the fuel system not flowing enough fuel for ideal combustion. Basically the ideal fuel to air ratio is not being met, too much air and not enough fuel which is BAD!

RXTech · 05-11-2005, 12:32 AM

I did get a new mechanic!! This is the 3rd guy I've been too! I've had my spark plugs and ignition coils replaced, and my fuel injetor flushed. I left the frist mechanic for political reasons, and got tired of the 2nd's BS telling me there's nothing wrong when it died in his parking lot after he told me there was nothing wrong and he had to push the car out of the way!!

***REN69*** · 05-11-2005, 01:50 AM

I was just gonna say.. if this guy can't fix it.. he aint a mechanic..

RXTech · 05-12-2005, 12:02 AM

Could I have done something to cause this or is this something that just happens as the car ages? I've got an appointment with the nearest Toyota dealer next week, am I going to cause serious damage driving it until then?