Rick 2014 Posted August 17, 2014 Share Posted August 17, 2014 How do I no if my lambda sensor Is dead.The reason I ask is every so often at the lights I get a little miss fire coming from the exhaust but when I pull away it drives fine.No check light comes on.I went to euro car parts to buy the lambda sensor I only have one sensor and brought it home to fit.I removed my old sensor and went to fit my new sensor to find the end of the plug was different.So I refitted my old lambda sensor and for strange reason I forgot to connect the multi plug but didn't notice this till today.I started the engine after fitting my old sensor and still no check light I even drove it round and its still doing the same thing.Its not all the time just every now and again.Still no check light.This morning when I popped the bonnet I was like fu** I didn't connect the multi plug back for the lambda sensor so I did and still no check light and it still drives the same as well.When I turn my ignition lights on my check light is there and turns off when engine is running as it should so I no it works.Im wondering if my lambda is dead because if its plugged in or it isn't nothing happens just occasionally I get this miss fire as before Quote Link to comment Share on other sites More sharing options...
stants Posted August 18, 2014 Share Posted August 18, 2014 If the lambda is unplugged you should be getting a cel light come up. Is it stored as an historical fault What did the old one look like when it came out ? Normally you can see how bad the condition is. Either that or the wires tend to go. Maybe the maff on its way out? Quote Link to comment Share on other sites More sharing options...
Rick 2014 Posted August 18, 2014 Author Share Posted August 18, 2014 The lambda sensor looked like it had a bit of what looked like a white powdery effect on it and a light black substance.the maf was replaced at subaru last yr by the last owner.my code reader wont read my car so ive no idea.when the maf is unplugged while the car is running it has a fit so i no its working.the fact there is no cel light when i disconect the lambda is weird and runs the same as when it was plugged in. Quote Link to comment Share on other sites More sharing options...
stants Posted August 18, 2014 Share Posted August 18, 2014 I thi k it's had it mine did the same looked like it was white hot on one side other was carbon have tou tried the green and black wires under sash to read codes ? 1 Quote Link to comment Share on other sites More sharing options...
Mr B Posted August 18, 2014 Share Posted August 18, 2014 Normal on these to generally have no CEL when disconnected. ECU sees a input value around normal stoich with sensor disconnected & cel rarely would come on. You can run sensor tests on car with appropriate kit or do some tests off car with multimeter & gas torch. Due to potential age of sensor & your issue you may be best getting a quality new one as could be the fix & also not too expensive as a testing step to your issue. Do check condition of wiring & plug though & don't buy dirt cheap fleebay sensors as they useless generally. Other things to check is knock sensor, ignition leads, plugs, crank, cam sensors, air leaks etc Quote Link to comment Share on other sites More sharing options...
Rick 2014 Posted August 18, 2014 Author Share Posted August 18, 2014 Hi Stanton i tried looking for these conectors and couldnt find any at all.may be i was looking in the wrong place. Mr b cheers for your input.i ordered the right sensor saturday and picking it up this evening. To add to this my missus she can smell fuel on start up.and every now and again you get a whiff of it in traffic and when i reverse onto the drive.ive looked at the tip of my exhaust and there is a bit of light black carbon effect on it. Quote Link to comment Share on other sites More sharing options...
Rick 2014 Posted August 18, 2014 Author Share Posted August 18, 2014 My plugs are a month old gapped at factory setting of 0.8 . Quote Link to comment Share on other sites More sharing options...
Rick 2014 Posted August 18, 2014 Author Share Posted August 18, 2014 At one point you could see the engine shaking then it stopped and drove fine Quote Link to comment Share on other sites More sharing options...
Mr B Posted August 18, 2014 Share Posted August 18, 2014 knock sensor perhaps, quite common on older subarus so worth looking at. Could even be likes of a leaking injector causing over fuelling & that more prominent at idle/low revs. Check throttle possition switch too . is maf clean ? is wiring harnesses/plugs in good order & earthing points good ? Quote Link to comment Share on other sites More sharing options...
Rick 2014 Posted August 18, 2014 Author Share Posted August 18, 2014 This all started from a fuel pump i got from a group buy a 290lph.it was ok for the few weeks then the car started spluttering and alsorts.restarted and it was fine.i went round a corner in trafford park and the car started spluttering again.so i pulled over in to a bus stop and thought what the !Removed! was that about.i thought carnt be the pump because its brand new.i tried starting the car and nothing.short story rac came out and tapped the tank and the car sprung into life.im told its a faulty pump and the rac man followed me home.a replacement pump came and its a million times better just every now and again i get this missfire but as you move its gone and drivez really well Quote Link to comment Share on other sites More sharing options...
Mr B Posted August 18, 2014 Share Posted August 18, 2014 Mmm hard be too helpful without hands-on really. worth checking fuel pressure & fuel regulator. Some of those upgrade pumps are junk, even genuine walbro are problematic once few years old plus poor fitting in tank can cause issues. needs looking into as if over fueling it costing you & will damage engine in time too. Quote Link to comment Share on other sites More sharing options...
Rick 2014 Posted August 18, 2014 Author Share Posted August 18, 2014 I only changed the pump because im after a remap and didnt want the pump to fail.ive still got my old pump but when i removed the old pump there was no filter on the end how ever it did work fine before hand Quote Link to comment Share on other sites More sharing options...
Rick 2014 Posted August 18, 2014 Author Share Posted August 18, 2014 Ive replaced the lambda sensor but because there is a fault already I don't think it would reset it automaticly so ive disconnected the Battery for a while.Ive also clean the maf with electrical contact cleaner there was flys on the gauze lol so cleaned them out.Also cleaned the ht leads to coil pack with the cleaner I did do other ends yet because of the access to it and !Removed! weather. Quote Link to comment Share on other sites More sharing options...
Rick 2014 Posted August 19, 2014 Author Share Posted August 19, 2014 I thi k it's had it mine did the same looked like it was white hot on one side other was carbon have tou tried the green and black wires under sash to read codes ? Ive spoke to her lol and ive got code 33 wich is lambda sensor which I replaced yesterday the code must still be stored? Quote Link to comment Share on other sites More sharing options...
Steveuk260.Esq Posted October 11, 2014 Share Posted October 11, 2014 Get yourself a Bluetooth obd2 scanner elm327 v1.5 and android app torque. I use them to read codes and reset them on my 2001 s-turbo. Quote Link to comment Share on other sites More sharing options...
Dino Posted October 13, 2014 Share Posted October 13, 2014 ok with a lambda sensor, a code reader will tell you if the "O2 sensor" is faulty - This is the same thing. With lambda sensor replacement, the code will not automatically disappear. You need to run the engine and stop/start at least 2-3 times before the ECU recognizes its been replaced. This is typical for a lambda sensor replacement. The EML will disappear when its ok and found to be working normally. If it remains on, the new lambda is either faulty or not recognised. Also, never try and clean a lambda sensor because these days a cleaner will destroy it, e.g. Petrol, Oil, WD40 etc will contaminate and ruin it. With normal running, the lambda sensor should be a light brown colour with the holes visible to allow the exhaust gases to be analysed by an electrical potential difference in the lambda so the ECU can read this info and make the engine adjustments accordingly. If you find the live wire (red) and the earth wire black (usually two or four wires or only two wires) then you can connect a potentiometer or volt meter and see if there is voltage in the wiring to the sensor - with the ignition on it should read above zero Volts - if not, first check the fuse in the fuse box and then if not this then you need the last resort of following the wiring back to see if there are any breaks and earth issues anywhere. Quote Link to comment Share on other sites More sharing options...
Rick 2014 Posted October 16, 2014 Author Share Posted October 16, 2014 I sorted this ages ago lol.Though I have been looking into these android tools Quote Link to comment Share on other sites More sharing options...
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