MR2 Roadster Owners Club

The Workshop => Maintenance, Problems & Troubleshooting => Topic started by: Acehole on June 29, 2010, 11:16

Title: Read the Code...
Post by: Acehole on June 29, 2010, 11:16
I Know this will probably hurt chances of selling car but i dont wanna sell it with a problem. cant believe my luck that its been fine all this time and today this happend  s:( :( s:( .

anyways the code is P0131 O2Sensor Circuit Low Voltage (Bank #1 Sensor #1)

an idea's on what this is and why this happens?

Car is running better than ever after full sevice from toyota so cant understand why this has come about :S

P.s engine light is not flashing just on.
Title: Re: Read the Code...
Post by: cclarke99 on June 29, 2010, 11:45
My manual only shows code 0130, which is one of the following

Open or short in heated oxygen sensor circuit
Heated oxygen sensor
Air induction system
Fuel pressure
Injector
ECM

From what is said on this forum, a faulty sensor is most likely. If you can see the output of the sensor on the code reader it should alternate between less than 0.4V and more than 0.5V.
Title: Re: Read the Code...
Post by: spit on June 29, 2010, 12:05
Quote from: "cclarke99"From what is said on this forum, a faulty sensor is most likely. If you can see the output of the sensor on the code reader it should alternate between less than 0.4V and more than 0.5V.

Yep that's your quickest way of getting to grips with the nature of the problem. Its OK to unplug the sensor to test it while the car is idling (RHS as you look in) - you want to measure voltage across the blue and white wires.

If you have more than a basic code reader, this data may be available through the unit for both banks and post-cat.
Title: Re: Read the Code...
Post by: wbarrwebster on June 29, 2010, 13:13
Hi,

Just a thought...what about swapping the sensors over?
That way you could confirm it it were just the sensor...or the heater curcuit on that sensor?

Yes, no?

B
Title: Re: Read the Code...
Post by: Acehole on June 29, 2010, 13:44
thanks all, is this a job u can do yourself and where is it actually located? worst ways then just a replacement sensor is it?

i bet its because of the aftermarket exhaust and hot weather we had it was just to much for the sensor.
Title: Re: Read the Code...
Post by: frogger on June 29, 2010, 21:42
Quote from: "wbarrwebster"Just a thought...what about swapping the sensors over?

This is a sensible suggestion, but does have some extra risk associated with it (due to how the o2 sensor hole threads love to strip themselves if corroded, or not removed at precisely the right angle).

By removing two sensors rather than one you could double the risk of stripping the threads in the manifold, but then again if your careful you shouldn't strip them anyway I supose  s:) :) s:)  

If the wirings fine you can be pretty sure a new sensor is required, so would be tempted to just replace the one.
If looking to save a few £ in the run up to selling, 2nd hand ones are fine so long as they're working!   s:lol: :lol: s:lol:
Title: Re: Read the Code...
Post by: Acehole on June 30, 2010, 09:03
No i wouldent buy a 2nd hand 1, im assuming this is just a sensor, so i take it the car is fine to drive while i try and grab 1 from somewhere over next week.
Title: Re: Read the Code...
Post by: frogger on June 30, 2010, 19:43
Quote from: "Acehole"No i wouldent buy a 2nd hand 1, Im assuming this is just a sensor, so i take it the car is fine to drive while i try and grab 1 from somewhere over next week.

It's a sensor whcich essentially controls the fueling, so might not run quite right but certainly isn't gonna go bang if you drive it about a little.
A bit of extra soot in the exhaust system and lower mpg will be the only real effects if its reverted to a safe map.
Title: Re: Read the Code...
Post by: Acehole on July 2, 2010, 07:55
solved thanks all.