Omega Owners Forum

Omega Help Area => Omega General Help => Topic started by: AndersH on 29 June 2007, 11:36:33

Title: Limp mode?
Post by: AndersH on 29 June 2007, 11:36:33
I think I experience the limp mode yesterday  :-/ I just set off and the car had no power but the revs were really high. I noticed that a light was on - presuming EML? I rebooted the car (I work in IT support) and it went off and all was fine again. When I got home I did the paperclip test while engine running and when not and got no fault codes. Is this anything to worry about? or could it just be a one off?
Thanks,
Andy
Title: Re: Limp mode?
Post by: Dazzler on 29 June 2007, 11:49:39
Its just a Vauxhall thing normally, sometimes you will start the car and it will be in limp mode with EML on. I just turn mine off and restart and the light will be out and everthing fine again.
Title: Re: Limp mode?
Post by: Marks DTM Calib on 29 June 2007, 11:56:02
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Its just a Vauxhall thing normally, sometimes you will start the car and it will be in limp mode with EML on. I just turn mine off and restart and the light will be out and everthing fine again.

Is it 'dangle berries'......soemthing was a miss...

Remember that GM dont make engine management systems and the one in this case is the Motorola Motronic as use on BMW's and all sorts....

If everything is in order the light wont come one and it wont be in limp mode.....ever.
Title: Re: Limp mode?
Post by: Dazzler on 29 June 2007, 12:08:29
Both my Omega and Zafira both do it very very occasionally, both been tested no faults and i have asked a couple of trusted garages that i know and they all said the same:- Its a Vauxhall thing, just a glitch..it kind of proves it when you turn off and restart and everything is fine.
If its bolloc*s then maybe you can explain this then...............
Title: Re: Limp mode?
Post by: Marks DTM Calib on 29 June 2007, 12:35:20
Its the 'vauxhall thing' I'm saying is 'dangle berries' because it is 'dangle berries'.....its the standard comment from un-skilled diag people who cant find a fault code and think bugger it, what do I do now...

It happens on all makes just as much which, is no surprise as tehre are only about 3 differnt makes of fuel injection system commonly used and they all use the standard operting system  (except VW who wrote there own whish is MUCH worse!) plus a few maps.

Reality is it might be as simple as a sticking EGR valve or a code 19 which, should store a non-present code and can be checked by using various actuator tests....but its rare for this to be done, its usualy a case of reseting the codes and seeing if it comes back by which time all your data is lost.

The trouble is there are very few skilled diag people about mainly thanks to engine management systems being 'complicated', idealy there woudl be skilled engineers and not basic technicians doing the complex stuff but, the outlets wont pay the money to employ them.

If you pick an engine sensor and ask most mechnics what it does and what it contributes to the system and how, they wont be able to answer it and those who can wont be able to do it for all the sensors.
Title: Re: Limp mode?
Post by: JamesV6CDX on 29 June 2007, 13:06:47
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its the standard comment from un-skilled diag people who cant find a fault code and think bugger it, what do I do now...

I wholeheartedly agree... I hate mechanics - hence why I do jobs myself!

Quote

If you pick an engine sensor and ask most mechnics what it does and what it contributes to the system and how, they wont be able to answer it, and those who can wont be able to do it for all the sensors.


Agreed... I'm pretty confident that I could answer questions about the common sensors now.. but I've come across plenty of "trained" mechanics that can't...
Title: Re: Limp mode?
Post by: TheBoy on 29 June 2007, 22:06:14
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Its just a Vauxhall thing normally, sometimes you will start the car and it will be in limp mode with EML on. I just turn mine off and restart and the light will be out and everthing fine again.
Sorry, I disagree.  The EML comes on for a reason, and its because the ECU has seen something out of expected range, or the values from multiple sensors do not make sense as a whole (ie one is misreading).

I'm afraid M_DTM is correct, if they are saying 'its a Vauxhall thing' they do not understand diagnosing modern systems.  I suspect if I took my Rover in with a similar fault that has no fault code, it would be 'its a Rover thing'

Diagnosing a modern engine management system is not simply a case of replacing the part the computer says is faulty. Diagnostic scanners only say what the ECU detected to be incorrect, it still needs skill to work out what is really wrong.

Take, for example, a surprisingly common fault on most marques - a stored MAF failure code.  This does not necessarily mean the MAF is faulty. It simply means the MAF reading is too low compared with the calculated expected value that the ECU expects from amount of fuel its injecting, and the exhaust feedback readings.  The real fault, of course, being unmetered air getting in the engine...

Does that make sense?
Title: Re: Limp mode?
Post by: TheBoy on 29 June 2007, 22:07:00
Quote
I think I experience the limp mode yesterday  :-/ I just set off and the car had no power but the revs were really high. I noticed that a light was on - presuming EML? I rebooted the car (I work in IT support) and it went off and all was fine again. When I got home I did the paperclip test while engine running and when not and got no fault codes. Is this anything to worry about? or could it just be a one off?
Thanks,
Andy
Was it engine EML under tacho, or gearbox warning under TID (assuming your GLS has a TID?)
Title: Re: Limp mode?
Post by: AndersH on 30 June 2007, 07:59:42
It was the one under the TID, without looking I believe it was a spanner in a circle. Does that sound like the gearbox warning?
Title: Re: Limp mode?
Post by: TheBoy on 30 June 2007, 08:54:46
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It was the one under the TID, without looking I believe it was a spanner in a circle. Does that sound like the gearbox warning?
Yup, and that fits in with symptoms.  Immediately check the ATF level, ideally changing it along with the filter, though it may be time for a new box.

I would hazard a guess that if you hooked it up to a Tech2, and read gearbox, you would have a code 8 (incorrect gear ratio).