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Shantal-Mod, Moderator
Category: Saab
Satisfied Customers: 10
Experience:  Moderator
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I have a 2007 Saab which I had converted to lpg in 2010. Over

Customer Question

I have a 2007 Saab which I had converted to lpg in 2010. Over the last 2 months, when running on lpg, an engine fault alarm has started to appear but it doesn't go into the 'limp home mode'. This has now happened on 3 occasions, each time after I've had the alarm reset by my maintenance garage and then run the car for about 230 miles. I now only run the car on petrol to avoid the possibility of it going into the 'limp home mode'. I've spoken to the company that installed the lpg and they tell me its a maintenance problem because lpg needs a better maintained ignition system than petrol (e.g. spark plugs). I've spoken to my regular maintenance garage and he tells me that he can't help because he doesn't know anything about lpg but as it is running okay on petrol he thinks the lpg installer needs to update the ECU (I'm told this means Engine Management System). Can you let me know if either is right, what I need to do to take this forward, if I would be risking damage to the engine on lpg, would the limp home mode eventually come on if I continued running it on lpg with the alarm on and anything else that would help.
Submitted: 2 years ago.
Category: Saab
Expert:  Shantal-Mod replied 2 years ago.
I'm Shantal and I'm a moderator for this topic.
I've been working hard to find a Professional to assist you with your question, but sometimes finding the right Professional can take a little longer than expected.
I was checking to see if you had already found your answer or if you still need assistance from one of the Professionals.
Please let me know if you wish to continue waiting or if you would like for us to close your question?
Thank you,
Customer: replied 2 years ago.


I have not found an answer and wish to continue waiting for assistance from one of your professionals


Expert:  Shantal-Mod replied 2 years ago.
Hello Roy,
I apologize as we have not yet been able to find a Professional to assist you. Do
you wish for me to continue to search for someone to assist you or would you
like for us to close your question at this time?
Thank you for your patience,
Expert:  Mike replied 2 years ago.
Hello and Welcome...

My name is ***** ***** Im happy to help / advise you --

Reading the above, it sounds very much as though passing the buck is going on somewhat - initially by the LPG installer... To be honest - if you have had the car regularly serviced I don't see an issue there - and likewise - even had you not! Its not really going to have any detrimental effect on the working of the Lpg system!

What has been missed though in the "proceedings" - I note you say you have when the EML ( engine management) fault light comes on, that you have had the system "reset"... Thats all very well - it puts the light out and away you have gone.... but, that light comes on for a reason... It means the EML / computer , has detected a fault somewhere in the engine management systems... petrol or lpg regardless - and it will have logged at least 1 fault code - When the light is on, there are fault codes then to tell you whats wrong ---- The garage that has "reset" the ecu and warning light - to do that , they have to delete the codes ( fault codes) ,... and then the light goes out. They are Im afraid not doing it right for whatever reason - Maybe its that they see the fault codes and dont like the look of them/ the job that ensues...or, they dont know what they mean.... but - either way - you cant just go away with the light switched off / reset - The fault light will come back on - because the basic fault hasn't been fixed.

So - where you are up to now.. The next time the EML comes on - you need to have, and I might perhaps suggest, another garage, read / scan the Ecu fault code memory - then working off the codes - they can fix the fault, whatever is causing this, properly. The system is then reset with the fault machine -and thats that.

Im afraid that for whatever reason, you have been lead something of a merry dance on this - So thats the way forward to get this sorted properly for you now.

Im very pleased to have helped you - Do let me know if you need anything more --

*** Meanwhile - - >>>> Please do click on the "OK/ Excellent ratings" for me - Thank you in advance for that...

You can and are most welcome to get back to me anytime you might need - clicking the OK ratings does not close you out at all..

Kind Rgds, MIKE.
Customer: replied 2 years ago.
Hello Mike,

Could you further clarify as follows.

I am told that the fault code indicates a fault at the sensor that regulates the air/petrol or air/lpg mixture. The concern I have about replacing the sensor is that having run the car for 1000 miles on petrol, without a problem, and the fault light coming on 3 times (each time after about 230 miles) when running on lpg, makes me think the fault is being caused by the lpg and not a faulty sensor. Do you think I should ignore this and have the sensor replaced?

The reason the lpg installer gave for questioning the adequacy of the maintenance was because an lpg system installation does not require any changes to be made to the car's EML / computer settings. Any requirements to change the settings would be for reasons the maintenance garage would determine for running on petrol, not lpg. Also lpg is more difficult to combust and less tolerant to poor ignition than petrol. The lpg installer said I needed to ensure the ignition system was adequately maintained i.e. spark plugs are of good quality and in good condition. Do you still think the ignition or any other maintenance issues to be irrelevant to the lpg operation?

Kind Regards, Roy
Customer: replied 2 years ago.
Relist: Incomplete answer.
It is now 12.05 GMT on 17 September 2014. I replied to the expert at 06.33 EST on the 16 September 2014 requesting further information but have not received an acknowledgement of my reply. I need your confirmation that my reply is being dealt with.
Expert:  Mike replied 2 years ago.
Hello again..

Thank you for your reply.

Im afraid I was not on the 16th - when you came back to me 2 days after my answer to you -
You then put your question as a re list which Im afraid causes a delay - you wouldn't likely know that but thats what happens Im afraid -

I am aware how the Lpg systems work etc as you have outlined above Roy - but Im a little confused as to exactly what you are asking me to clarify re my answer to you.. in view of that -

Could you please just perhaps re explain - and will get back to you ..

Please note - I wil be off this afternoon but will be back on shift later today / eve... at which time I will get back to you asap after I receive your reply..

Kind Rgds, MIKE................................
Customer: replied 2 years ago.
Hello Mike,

In view of the fact that my maintenance garage told me the fault code indicated a fault at the sensor regulating the air and fuel mixture, but the sensor appears not to be a problem when operating with petrol, I am concerned that a new replacement sensor would not resolve the problem and would still raise the same fault alarm when operating on lpg.

My maintenance garage has recommended the sensor is replaced but I am needing to know if there could be issues I should be aware of, concerning the lpg operation, that would question this recommendation.

The fault code has appeared 3 times so far when using lpg and has indicated the same fault each time.

Kind regards, Roy
Expert:  Mike replied 2 years ago.
Hello there Roy -

Thank you for your reply and further info..

Im with you now - Im sorry for the misunderstanding..

The sensor you refer too - that the garage tells you they have a fault code for - what is that ? Is it the MAF ( air flow sensor / meter ..) or perhaps the lambda sensor?

Plus - do you happen to have / know the actual code that was retrieved - ?

Rgds, MIKE.....................................
Customer: replied 2 years ago.
Hello Mike,

He described it as a lambda sensor costing around £150-£170 but he didn't give me the code.

Regards, Roy
Customer: replied 2 years ago.

Hello again Mike,

Following my reply, providing you with the information you requested, I do not appear to have received anything further. Can you confirm that you are still dealing with it and let me have some idea of when I should expect to receive your response.



Customer: replied 2 years ago.
Relist: Incomplete answer.
I first asked my question at 11.43 EST on Wed 10 September 2014. After responding to requests for further information from the SAAB expert Mike I still await a complete answer. I provided him with his requested information at 05:17 EST on Thursday the 18 September 2014 telling him it was a Lambda sensor. I then asked him, at 16.15 EST on Friday 19 September, to let me know if he had received the information and when I could expect to receive an answer but still await his answer. 12 days having elapsed this is very unsatisfactory. If Mike cannot answer the question then another expert needs answer it.
Customer: replied 2 years ago.
I am still awaiting a response.

I have seen, on the JustAnswer website, a statement saying my question was answered in 1d 16h. How can you make such statements when you know I have been waiting for 14 days without any indication as to when I will get the answer I need. Are you doing this intentionally?

Having provided you with all the information you have requested, how can you justify keeping me waiting like this.

If you cannot answer the question, as I now have reason to believe, please tell me so that I can then have a refund of my payment.
Expert:  Shantal-Mod replied 2 years ago.
Hello Roy,
I've been working hard to find another Professional to assist you with your question, but sometimes finding the right Professional can take a little longer than expected.
I wonder whether you're ok with continuing to wait for an answer. If you are, please let me know and I will continue my search. If not, feel free to let me know and I will cancel this question for you.
Thank you,
Customer: replied 2 years ago.

Hello Shantal,

Unfortunately you were working hard to provide an expert on the 12 September, that's now 2 weeks ago. If you had an expert available I'm sure you would have found him by now.

As I do not wish to waste any more time on this would you please cancel the question and let me know when I am to receive the return of the £20 fee that I paid.

Thank you,


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