120D Yellow Engine Light

Post Sun Oct 28, 2012 2:35 pm

Hi guys,

The trusty family 120D (2009 46K) was running fine last night. This morning however, the yellow engine warning light came on (it's not the emissions related light) and the engine is in "limp mode". Car is not due a service and covers mostly motorway miles at all times.

No irregular engine smoke and engine doesn't sound like there's anything mechanically wrong. Very poor throttle response though, but i'm putting this down to the fact its in Limp Mode.

Any initial ideas here??

Thanks for any help!

Post Sun Oct 28, 2012 2:43 pm

Is it down to the clocks going back, perhaps?

Post Sun Oct 28, 2012 7:06 pm

Needs to be code read and work from there.

Did you ever get to the bottom of the noise?

Post Sun Oct 28, 2012 7:55 pm

Been told the MAF sensor is a common culprit, so will remove that tomorrow and clean it up and see what happens. Will then get it code -read. The excessive noise I was talking about a while ago quietened down a bit after the oil change. It's definitely not the dreaded mechanical disaster noise which was spoken about!

How much do BMW charge for a diagnostic test? Will an independent be able to access ALL codes?

Cheers

Post Sun Oct 28, 2012 9:13 pm

Most BMW dealers will try and sting you for an hours diagnosis which will cost anything between £120-£200 PH depending on which part of the country you are in but if you specifically ask for just the fault codes to be read and printed out for which they should only charge you for 15 min labour so a quarter of their labour rate.

TBH, a specialist with Autologic diagnostic software will be able to read the fault memory just as well and will most likely be a lot cheaper.

Post Sun Oct 28, 2012 9:36 pm

Jesus, that's a lot of money just to plug the car into a computer! If it was to go to BMW, it would be Vines Gatwick in Three Bridges.

Will most likely get it done at an independent / specialist in that case. Additionally the BMW dealership is 15 miles away and it'll be painful to drive that distance in limp mode, not to mention worrying about possible damage being caused to the car!

Post Sun Oct 28, 2012 9:41 pm

HJG-E30 wrote:Jesus, that's a lot of money just to plug the car into a computer! If it was to go to BMW, it would be Vines Gatwick in Three Bridges.

Will most likely get it done at an independent / specialist in that case. Additionally the BMW dealership is 15 miles away and it'll be painful to drive that distance in limp mode, not to mention worrying about possible damage being caused to the car!

I used to work at Vines Gatwick! Left there 6 months ago and im glad i did!

Where abouts are you located?

Post Sun Oct 28, 2012 9:47 pm

Small world! Is it a bad dealership?! A friend of mine was on an apprenticeship there and left because apparently new management took over and he was no longer enjoying his time there.

I'm located in Burgess Hill (RH15)

Post Sun Oct 28, 2012 9:55 pm

HJG-E30 wrote:Small world! Is it a bad dealership?! A friend of mine was on an apprenticeship there and left because apparently new management took over and he was no longer enjoying his time there.

I'm located in Burgess Hill (RH15)

How long ago was that? What's their name?

The techs are ok or the ones i worked with anyway but since i left others have to including the master tech. The dealer principal and the service manager are complete and utter w@nkers, WORST person i have ever worked for!

Service reception were ok but a bit hit and miss at their job. If you ever have to go there ask for Matt and tell him Barry with the E30 sent you.

If i wasnt so busy this week i would offer to help as i have latest dealer level diagnostic software but im sure you need to get this sorted ASAP.

Post Sun Oct 28, 2012 10:06 pm

The last time I was up there was last summer, to pick up an O-ring, and the battery died on my Dad's motorbike and somebody in the workshop was lending a hand until the AA turned up. I remember seeing an E30 parked up inside, was it yours by any chance?!

My friend's name was Sam Blackburn; we went to college together before he left to go to BMW.

That's very considerate of you, thank you for the thought. I'll keep you posted on any updates. Hope it's minor!

Post Sun Oct 28, 2012 10:35 pm

Yes i know Sam! Good lad!

If it was a black Sport with alpinas then it will have been mine.

Post Mon Oct 29, 2012 9:30 pm

Removed the MAF sensor today, just to have a look but it didn't look contaminated in any way. Also tried what I used to do with an old Fiesta of mine - disconnecting and re-connecting different sensors a few times.

Got it code-read and the code for the MAF and Air Temp Sensor came up. Mechanic claimed this is because they have been disconnected (but reconnected) today. But surely one of them must've tripped the engine light in the first place, regardless?!

Cleared the fault codes and car is now running fine and the light is off. Any ideas what caused it to come on in the first place?!

Post Mon Oct 29, 2012 10:18 pm

Without seeing exactly what faults were stored it's hard to say. Your mechanic was right in that just unplugging things would have put fault codes in and not have helped with the fault diagnosis and elimination.

You'll just have to run it and see if the fault returns then get it read again this time with touching any electrical items with the ignition on.

Post Mon Oct 29, 2012 10:25 pm

ah ok fair enough, so used to older vehicles! Just out of interest what's the most serious issue that can cause the "yellow light - reduced power" scenario? I'm assuming it can't be too serious if the engine is allowed to run with the warning light on. I understand the Red Engine Light means you're unable to continue driving the car...