Grrrrrrr. Lambda Sensors
 

Why oh why! I replaced the sensor on Saturday, did about 45 miles since then - all with no light and lovely and smooth - and as I pulled in to Shell at lunch the damn light came on again!!!

Got home and read the codes - 1133 - O2 Sensor Insufficiant Switching (Bank 1 Sensor 1)

Right people, I need thoughts. What can be causing this. Its NOT the Front 02 Sensor - as I say its got 45 miles under its belt and is brand new Bosch.

Am ordering new spark plugs today - wouldnt be surprised if they are fouled, but what else can cause 02 sensors to throw up that fault?

Cheers,

James - Coming to the end of my patience!

when the light is on is there any difference in the way it runs?

Only reason i ask is because Ive come across a few cars at work that throw up o2 sensor faults and even on the live data show the o2 sensor not switching but when i looked into it in more detail it turned out to be a faulty air Mass sensor giving false readings which messed the fueling up which in turn messed the O2 readings up.

But the cars also ran badly very flat and hesitant.

Runs a little rougher - slight vibrations through the engine, slight hunting by about 100rpm or so.

Will go for a short drive with OBD2007 on, and have a glance at the data afterwards to see the fuel/air ratios etc. that it has logged.

Will see if I can get the MAF off tonight and take a look inside to see if there is any obvious dirt or damage on/to the filaments.

It's not normally obvious to look at it but if it does run slightly off try just unplugging it and running it, it will log another fault but as its unplugged the ECU will use other info from other sensors to sort out the fueling and if the air flow meter was giving readings that were way off it should run better disconnected

Unplugged the MAF - Car started running lumpier so I'm reading into that as MAF is OK - or at least in a workable state even if its not in the best of conditions?

Also, it threw a light on the dash for my ETS, and when I turned the engine off again the cooling fan turned on and wouldn't turn off. Plugged the MAF back in and restarted the car and it eventually stopped. Went for a short drive around the block with OBD2007 Lite logging on the seat next to me (very short drive!) and kept a screenshot of the end of it. Bear in mind I didn't go over 25/30mph the whole time ..

Hope its readable, and maybe helpful to someone in pointing out a problem?

Oh and PID 0x03 - Fuel System - when sat in the drive was switching between Open Loop (System Fault) and Open Loop (Driving) or words to that effect.

http://volvoforums.org.uk/picture.ph...pictureid=3207

how old is the cat...............?????

Ok sound like the MAF is ok, on your live data screen can you bring up bank1 sensor1 voltage and see if when the engine is up to running temp its switching from between around 0.2 up to 0.8 and switching in a nice regular way every second high low high low.

Gareth - no idea on how old the Cat is - Probably as old as the car!

dpbayly - The closest I can get to the Voltage for the 02 sensor is what you see on that screenshot. Thats where it was sitting earlier, but I have seen it sat at 0.430/0.435. Havn't seen it switching back and forth though but it will change if I am going up/down through the revs - not by a lot though.

I assume the car has a ME7 engine management system.

I'd suspect the sensor you've fitted is either the wrong one or faulty, the system requires a wideband sensor.

The fact the system is not going into closed loop control would tend to confirm this.

Did you match the part number from the old sensor with the new one?

Chris - Yes I did - admittedly not until after I had bought the sensor and had them both infront of me, but the number matches perfectly.

It did go into a Closed loop for a few seconds with something in brackets behind it (but Ive forgotten what that said now! Something about "Driving" ) then back to Open with fault, then if I ran the throttle up a little a few times it would pop back into open with fault etc etc ...