Help - OBDII error code "system running lean" - Toyota Yaris Forums

Gazdaman · 05-14-2009, 11:06 AM

Hi,

my girlfriend's had a 99 Yaris for a few years now. The engine light's been on for a while, and it's been a pain picking up off idle, worse when cold.

It runs fine, other than this flat spot very low in the rev range. And returns good mpg.

Anyway, I bought an OBDII error reader which read code p0171 which is "system running lean".

So I'm guessing it's a sensor, but I don't know where. I replaced the spark plugs recently which didn't help. A clogged air filter would make it run rich. So I'm thinking dirty injectors? Dodgy fuel management? Lambda sensor?

Anyone got any input?

Ga

05-14-2009, 11:06 AM	#1
Gazdaman Drives: Corsa 1.2 8v Join Date: Jan 2009 Location: Leicester Posts: 5	Help - OBDII error code "system running lean" Hi, my girlfriend's had a 99 Yaris for a few years now. The engine light's been on for a while, and it's been a pain picking up off idle, worse when cold. It runs fine, other than this flat spot very low in the rev range. And returns good mpg. Anyway, I bought an OBDII error reader which read code p0171 which is "system running lean". So I'm guessing it's a sensor, but I don't know where. I replaced the spark plugs recently which didn't help. A clogged air filter would make it run rich. So I'm thinking dirty injectors? Dodgy fuel management? Lambda sensor? Anyone got any input? Ga