240 General: - Running with Lambda light on.

146ken · Mar 3rd, 2008, 17:13

I am looking at rescuing the 240gl estate that is up for £200 on the sales forum. I do have a worry though that the owner says it has been running for many years with the Lambda light on. I am no mechanic and don't want to be faced with major engine issues.
What possible problems can be caused by running without addressing this issue?

Glen Morangie · Mar 3rd, 2008, 17:25

I hope you do get it - I looked at it myself, but I just haven't got room.

I think (but may be wrong, as the lambda business is relatively new to me) it sounds as if the engine is running rich, which will take out the AMM and the cat.

So you will probably need an AMM and a lambda sensor, but otherwise there shouldn't be too much to worry about. You don't have to have a catalyser for the MOT necessarily, as it's a 1991 car. If you dispense with the cat you will have to either substitute a section of exhaust (these are available) or clear it out. It may be the cat has nothing in it, as otherwise it might have become blocked by now.

As soon as it's running properly any carbon build up will clear on your first motorway trip, overfuelling is less likely to be damaging to the engine than lean running in the long term, other than the items mentioned.

You'll probably have to do all the normal things, like cambelt, plugs, hoses, filters etc, as it sounds like it's had a 'zero maintenance' regime - just shows how much neglect a 240 will stand.

Strangely there is another just like it on ebay at the moment, also missing a door trim and with a broken bonnet hinge.

Velorum · Mar 3rd, 2008, 18:32

Sometimes even when the running problem that caused the light to come on is rectified the light remains on and needs to be reset. When Ive done this is in the past I check that Ive got the radio code and then disconnect the battery for a few minutes. Worth a go.....................

Glen Morangie · Mar 3rd, 2008, 18:38

Quote:

Originally Posted by Ian Hutchinson

Sometimes even when the running problem that caused the light to come on is rectified the light remains on and needs to be reset. When Ive done this is in the past I check that Ive got the radio code and then disconnect the battery for a few minutes. Worth a go.....................

If the car's running I wouldn't recommend trying a reset until you get home. The ECU stores faults and makes adjustments, it's possible other adjustments have been made to counteract this (the idle is 1500 RPM) - it might work, but if it doesn't you're stuck until the ECU re-learns the faults.

Just my opinion of course, not everyone will agree.

Suterman · Mar 3rd, 2008, 18:54

The lambda light comes on to notify you as a buyer that you are getting a bargain.

Its a good point about the cat, if the engine has been running rich for a long time it may have damaged the cat. It would be pointless trying to diagnose the problem until you are sure the cat is ok as a blocked cat damages the o2 sensor or at least causes it to give a dodgy reading leading to a bad air fuel mixture.

I would say the AMM will be ok as the car will barely run if it's faulty.

Once you have established the cat is OK, clean up (replace would be best, to be certain) the 02 sensor reset the ecus and try it again/read the codes with the OBD and see what it says, it might come up with a few things. If there is still a problem with the mixture (EFI) then the lambda light will come back on.

Raid the scrapyard for the parts needed.

Glen Morangie · Mar 3rd, 2008, 19:05

If you do want it you may need to be quick now - as anyone reading this thread who might have been put off will be thinking - hmmm, a hundred quid's worth of parts and it could be back on the road!

Mar 3rd, 2008, 17:13	#1
146ken VOC Member Last Online: Jul 16th, 2022 19:08 Join Date: Feb 2006 Location: Exeter View Photos By: 146ken	Running with Lambda light on. I am looking at rescuing the 240gl estate that is up for £200 on the sales forum. I do have a worry though that the owner says it has been running for many years with the Lambda light on. I am no mechanic and don't want to be faced with major engine issues. What possible problems can be caused by running without addressing this issue?

Mar 3rd, 2008, 17:25	#2
Glen Morangie Economy motorist Last Online: May 16th, 2024 23:05 Join Date: Dec 2004 Location: London	I hope you do get it - I looked at it myself, but I just haven't got room. I think (but may be wrong, as the lambda business is relatively new to me) it sounds as if the engine is running rich, which will take out the AMM and the cat. So you will probably need an AMM and a lambda sensor, but otherwise there shouldn't be too much to worry about. You don't have to have a catalyser for the MOT necessarily, as it's a 1991 car. If you dispense with the cat you will have to either substitute a section of exhaust (these are available) or clear it out. It may be the cat has nothing in it, as otherwise it might have become blocked by now. As soon as it's running properly any carbon build up will clear on your first motorway trip, overfuelling is less likely to be damaging to the engine than lean running in the long term, other than the items mentioned. You'll probably have to do all the normal things, like cambelt, plugs, hoses, filters etc, as it sounds like it's had a 'zero maintenance' regime - just shows how much neglect a 240 will stand. Strangely there is another just like it on ebay at the moment, also missing a door trim and with a broken bonnet hinge. Last edited by Glen Morangie; Mar 3rd, 2008 at 17:35.

Mar 3rd, 2008, 18:32	#3
Velorum VOC Member Last Online: Apr 17th, 2023 20:49 Join Date: Dec 2004 Location: Newquay	Sometimes even when the running problem that caused the light to come on is rectified the light remains on and needs to be reset. When Ive done this is in the past I check that Ive got the radio code and then disconnect the battery for a few minutes. Worth a go..................... __________________ Past Volvos 340's (2), 240 saloons (4), 240 estates (5), 740 estate (1), 760 saloon (1), 940 saloon (1), 940 estate (1)

Mar 3rd, 2008, 18:54	#5
Suterman 240 Turbo Last Online: May 28th, 2024 14:49 Join Date: Jan 2006 Location: shropshire View Photos By: Suterman	The lambda light comes on to notify you as a buyer that you are getting a bargain. Its a good point about the cat, if the engine has been running rich for a long time it may have damaged the cat. It would be pointless trying to diagnose the problem until you are sure the cat is ok as a blocked cat damages the o2 sensor or at least causes it to give a dodgy reading leading to a bad air fuel mixture. I would say the AMM will be ok as the car will barely run if it's faulty. Once you have established the cat is OK, clean up (replace would be best, to be certain) the 02 sensor reset the ecus and try it again/read the codes with the OBD and see what it says, it might come up with a few things. If there is still a problem with the mixture (EFI) then the lambda light will come back on. Raid the scrapyard for the parts needed. __________________ 1991 240 Turbo GL 1992 940 GL 1996 940 GLE Turbo Auto 1985 Bedford CF2 B230E

Mar 3rd, 2008, 19:05	#6
Glen Morangie Economy motorist Last Online: May 16th, 2024 23:05 Join Date: Dec 2004 Location: London	If you do want it you may need to be quick now - as anyone reading this thread who might have been put off will be thinking - hmmm, a hundred quid's worth of parts and it could be back on the road!

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