Hi all,
It looks like one of the previous owners has either removed the check engine light bulb or its failed as using my OBD reader and Torque Pro app I found a few error codes when I got the car, cleared them and they have returned - I know the bulb doesn't work correctly as it doesn't come on when you turn the car on (meant to come on then go off).
Anyway, I have 3 codes stored on the ECU, all of them are for the O2, I did notice a few pops on the overrun, might have a slight exhaust blow which might be causing the engine to overfuel perhaps, anyway the codes are:
P0135 - O2 sensor heater circuit, bank 1, sensor 1
P0141 - O2 sensor heater circuit, bank 1, sensor 2
P0155 - O2 sensor heater circuit, bank 2, sensor 1
I am guessing that I have an issue with all 3 O2 sensors or as all 3 are showing errors perhaps something is unplugged for the whole O2 heater circuit? Anyone know what the most common issue is - currently running a decat manifold, stock main cat with TTE exhaust.
Just having a read around it seems that although the heater circuits might have failed the sensors themselves might be fine? I see that I can simply install a resistor into the heater circuit to clear the fault but I just need to check if the sensor itself is working correctly - my guess they are as I don't have a code saying that its out of spec, more that the heater circuit has gone meaning poorer fueling when the engine is cold/exhaust not up to temp?
m http://www.toyotaownersclub.com/forums/ ... or-bank-1/ (http://www.toyotaownersclub.com/forums/topic/88814-oxygen-sensor-bank-1/) m
To be honest, if you've noticed it's running poop, you might be best off replacing the lot.
Dick Sloan (affiliate breaker) sells them for about 22 quid delivered for working 2nd hand ones. All of mine are 2nd hand and work smashing.
It's not unheard of to have all be dead. If the light isn't working, who knows over how long these have started failing.
I would say you pretty much have that nailed.
Re check light. Another alternative is some tape has been used to mask it. Worth a look. Binnacle is easily removed.
Are you getting live data in torque?
If got moving data, would imply actual sensor is working esp when in open loop sensor fed fueling.
They do work less well over time. If fueling isn't great and they've been in long enough for all three to have their heaters fail, might be time to replace them.
Thanks for the help guys, will look to replace all of them, to be fair the car is running fine, its more just the light throttle that might need attention and might also cause issues when it comes to the MOT in the future. With regards to the actual bulb, its not actually on meaning its been removed or has blown, noticed that some of the backlights aren't working either so will look to overhaul the unit, I have already removed the binnicle and unscrewed it but not unplugged it yet - looks like I have to take the back of the unit off to get to all the bulbs?
I will also check to see if I am getting readings, if all the O2 sensors have failed (possible due to the mileage) would the engine be running on a fixed fueling map? I did however noticed that the fuel trims were being adjusted so I am guessing some are working, will look to replace anyway, easy to do.
Ahh the sneaky gimps may well have chiselled it off the circuit board and taken a few others with it, ask me how i know s:evil: :evil: s:evil:
If you want you can save few quid by doing the resistor fix on the post cat sensor, have a search iirc theres a recent thread with the best place to buy the resistor. It's 3-4 quid as opposed to £60
The heaters only affect the sensor performance as the system warms up. They don't prevent the sensors from working once all is nice and hot. The sensors do get 'sluggish' over time, though.
Hmm I will see if I can get readings off the OBD reader in terms of what they are outputting (if they are), the car runs fine so it might just be the heater failure to get them up to temp, I do check for codes every week usually, its actually quite nice not to have a bulb lighting up on the dash for once!
Will look to fix/sort out the lighting behind the instruments, happy that its just a heater error rather than something reading high/low, will also be taking off the rocker cover in the next few days to check chain tension and need to replace the O ring for the chain tensioner as its leaking and has been for quite a while!
The eml is an led attached to the circuit board, backlighting is provided by twist in bulbs you can see from the back of the unit.
It's not unknown for scroats to just put a bit of tape over the eml led and put it back together, or the more scroaty ones chisel the led off the board.
I have just plugged the reader back in after my drive to work so everything is up to temp, I can see the O2 voltage readings, 2 of them seem ok and are updating fairly well, one of them is showing 0V:
Bank 1, sensor 1 - voltage showing
Bank 1, sensor 2 - 0V
Bank 2, sensor 1 - voltage showing
Looks like I need to replace the O2 sensor in the cat to get readings on all sensors, as mentioned before the heaters are only there to heat up the sensor to operating temp if the exhaust system isn't up to temp.
Will look into the LEDs/backlights, might just be a bit of tape but will find out soon, not too worried as the other lights are ok and I do check codes regularly - does the rear simply click off to check the LEDs?
Quote from: "m1tch"does the rear simply click off to check the LEDs?
Just follow this, 7 screws: http://www.mr2roc.org/phpBB3/viewtopic.php?f=47&t=61863
Quote from: "onion86"Quote from: "m1tch"does the rear simply click off to check the LEDs?
Just follow this, 7 screws: http://www.mr2roc.org/phpBB3/viewtopic.php?f=47&t=61863
Perfect, thanks for that s:) :) s:)
This really is a top friendly helpful site.
As demonstrated by this thread alone
Quote from: "Ardent"This really is a top friendly helpful site.
As demonstrated by this thread alone
I agree s:) :) s:) I am feeling really welcome as a newbie, thanks to this thread I have just removed the instrument cluster and got into the back of it, seems that someone has put a small bit of paper or something to cover the check engine light but it might have been quite a while ago as those connectors on the back felt like they hadn't moved for a very long time.
Anyway, will look to get a new cat O2, need to put the plugs back in before I can start it up to check it hasn't started working again but it seems that the O2 sensors in the manifold were giving a reading but the cat one wasn't - will check the connector just in case its come lose of something though.