emissions light

E

etedlm

Member
 kingston-upon-hull,east yorkshire.
well after reading posts about people who's emissions light has come on i thought i was one of the lucky ones as mine had never come on,all iv'e ever put in my car is tescos s/u until i had no choice over the weekend than to put shell vpower s/u
in it,£40 worth.10 miles down the road the emissions light comes on!! :( the car seems to be running fine but its going in on weds just to be on the safe side.
i know alot of you out there put vpower in your cars but how many who put vpower in thier cars have also had problems with the emissions light?
it could just be a coincidence but it makes you think :o :o
 
ive used V-power in my z4m since it was new..... ive never had an emissions light come on since owning the car ......(touches wood violently)
 
I've had the emissions light temporarily for bad fuel, it rights itself. If it stays on, it will be the lambda sensor, & I can't see that being fuel related?

someone correct me if im wrong :)
 
interesting that.......I've been using V Power and Tesco 99 (mainly v power though) and my emissions light came on, stayed on for two days then went off and then three weeks later came and on stayed on and now I need a new O2 sensor which is being done under warranty.

I think its probably coincidence and a higher proportion of M users will be using V-Power or the like anyway. I think they just fail due to excessive build up of carbon deposits.
 
I'm not saying it had anything to do with it, but I was running mine almost exclusively on Tesco 99 until the engine failure. Since then it's had nothing but Shell put in (standard Shell unleaded when V-Power pump is empty).

My engine failure started with an orange emissions light and rapidly became something bigger, despite me refusing to drive it once the light came on and it had started misfiring slightly. The only people who drove/revved it after that were the Mondial technician and the dealer. The next time I saw it the slight misfire had become a major car-rattling misfire.
 
got the results back from the plug in and its showing the lambda sensor on bank 2 has failed.
 
I've had this twice, both times it was the Sensor at fault. No biggy, fixed under warranty.
 
etedlm said:
Andy said:
what did it cost then ?
Click to expand...
dont know yet as the sensor doesn't arrive until the morning.
Click to expand...

I'd be very interested to know how much it costs as I am highly suspicious that I may have an O2 sensor problem and my warranty expired back in November...
 
I had the emissions light come on about 18 months ago when my Z4MC was still in warranty and BMW replaced all four O2 sensors and the MAF sensor just to be sure. Anyway, a couple of weeks ago had the emissions light on again. Car ran fine for a day or so and then started to run lumpy with varying idle.

Did a bit of reading on some of the forums and brought an OBD port scanner from amazon for £26 and read the code which turned out to be the front cylinder bank pre-cat O2 sensor. Brought the sensor from BMW for £140 inc VAT (was actually the cheapest you could get, internet shops wanted £165) and a set of crows foot wrenches from ebay and fitted it myself.

It wasnt too hard to get the old one out, you need two extension bars connected together with a 22mm crows foot wrench on the end to get down to the sensor. You can see the sensors on the manifold if you look down the back of the engine bay on the drivers side. Once the old one was loosened up you disconnect the cable to it which is under the engine cover and take the sensor out. You then have to jack the car up and get underneath to put the new one in, this is the tricky bit as you cant actually see the tapping on the manifold so you have to feel where the tapping is and then move the sensor into position. You need to be careful so not to get any crud on the sensor head. Once its in and finger tight hook the cable up in the engine so you can reach it from above, drop the car back down, get the cable and plug it back in, tighten the sensor up and thats it. I was worried that the sensor was faulty as the emissions light stayed on even though the car was running perfectly. The car basically has to reset itself on its ECU, this took about a day of driving and the light put itself out. I did try disconnecting the battery but it didnt reset the light, you either wait for it to reset or take it to BMW to reset it, the fault gets hard coded onto the ECU so disconnecting from power makes no difference.

Anyway, i wouldn't hesitate to do this again as it was pretty easy if you have basic car skills, the right tools and a bit of patience. I could do another one in about 30mins I reckon. BMW will charge an hours labour probably. This rough guide is to replace either front (pre-cat) sensors, the post cat ones require the centre of the exhaust to be removed i think so might be a bit more difficult. One other word of warning, dont do this until the car is cold... exhausts and engines (especially 3.2litre ones) get very hot! Hope this helps someone.

This shows the front (pre cat) sensors;

http://www.realoem.com/bmw/showparts.do?model=DU92&mospid=49422&btnr=18_0661&hg=18&fg=10

This shows the rear (post cat) sensors;

http://www.realoem.com/bmw/showparts.do?model=DU92&mospid=49422&btnr=18_0658&hg=18&fg=10
 
Good write up, & sure to be more relevant as more & more of these fall out of warranty.

So there's 4 - didn't realise this, 2 precat and 2 postcat, one for each bank of 3 cylinders... cool.
 
Thanks Andy, hope it helps someone.

Yes the cylinders are split into two banks of 3, so cylinders 1-3 are called bank 1 (3 closest the nose of the car) and then banks 4-6 at the rear of the engine. The manifolds come off each bank and stays seperate, each having an O2 sensor, then the exhaust joins together at the CAT, split again where you have the post CAT O2 sensors and away to the exhaust back boxes.

After all why make it simple when you can make it really complicated! :roll:
 
iv'e got my car back and the car seems to be running better than before the emissions light came on :D i took my car to an independent bmw specialist in hull so what iv'e been charged should be cheaper than a stealership.system test £60,lambda probe £141.27,then the labour charge £70 which came to £271.27,then the dreaded vat which was £47.47 giving a total of £318.74.
 
You must log in or register to reply here.
Back
Top Bottom