Discussion
Some time ago my monaro started showing an eml fault.
My local garage apparently did not have the necessary software to read what was wrong.
I took it the nearest Vauxhall dealer,Peter Vardy in Perth as they assured me they had the means to read and find out what the problem was.
It turns out they diagnosed it as a faulty O2 sensor.
Both sensors purchased from Monkfish and replaced.
Fault still present.
Since then It has been in and out of the garage,the ecu has been sent away for testing,but to no avail.
Apparently it is not reading data from the sensors and throwing up the fault.
My mechanic seems to have hit an impasse and is at a loss at what to try next.
Any thoughts would be gratefully received.
Has anyone had similar problems.
My local garage apparently did not have the necessary software to read what was wrong.
I took it the nearest Vauxhall dealer,Peter Vardy in Perth as they assured me they had the means to read and find out what the problem was.
It turns out they diagnosed it as a faulty O2 sensor.
Both sensors purchased from Monkfish and replaced.
Fault still present.
Since then It has been in and out of the garage,the ecu has been sent away for testing,but to no avail.
Apparently it is not reading data from the sensors and throwing up the fault.
My mechanic seems to have hit an impasse and is at a loss at what to try next.
Any thoughts would be gratefully received.
Has anyone had similar problems.
Hi I don’t know what tests you mech has already done but I would be testing the o2 sensor readings at the sensors then testing the same wires where they connect to the ecu & comparing the 2 readings (should be the same), if that’s ok you need to check the earths etc for ecu. What were the fault codes by the way ? Shaun
Thanks for the prompt reply.
I`m not sure exactly how it was tested but from what I have been told was that the readings with the o2 sensors connected and not connected were the same.
I don`t know if that makes sense or not .
Apparently there were no codes stored or his machine was not capable of reading them.
Its great fun living out in the sticks here where even a second opinion is an age away.
I`m not sure exactly how it was tested but from what I have been told was that the readings with the o2 sensors connected and not connected were the same.
I don`t know if that makes sense or not .
Apparently there were no codes stored or his machine was not capable of reading them.
Its great fun living out in the sticks here where even a second opinion is an age away.
On my iphone i downloaded an app called four stroke and bought a wifi obd reader and it shows from memory o2 voltages plus lots of other bits , the app needed about 5£ upgrade payment to do this , it may help to get to the bottom of the issue , my 02 sensors on the monaro were hardly working but showed no cel , but when i changed there was a little quicker engine pick up but that was it , have you had a sports exhaust fitted and 02 sensors need the adaptor to make them not show a cel , is car driving ok , assiming it’s a monaro is it showing any codes on the engineering mode , is it showing any other symptoms ?
Obvious thing to test is wiring.
Apply a voltage in the normal range 0-1v to the relevant pins and see if you can see this on live data with an appropriate can tool
And exactly what is the fault ? there should be multiple codes relating to things like that to help narrow down exactly what the problem might be
Some cheap OBD readers might get you there, but you might need to spend a little more, likes of this, or if there is similar from Ozzie land just in case ( eg EFI Live scan tool etc )
http://www.palmerperformance.com/
Whilst OBD is supposed to be generic...it isnt always and there can be regional variations hence all UK scan tools may not work correctly if at all. But ideally you'll want more than just fault codes.
Apply a voltage in the normal range 0-1v to the relevant pins and see if you can see this on live data with an appropriate can tool
And exactly what is the fault ? there should be multiple codes relating to things like that to help narrow down exactly what the problem might be
Some cheap OBD readers might get you there, but you might need to spend a little more, likes of this, or if there is similar from Ozzie land just in case ( eg EFI Live scan tool etc )
http://www.palmerperformance.com/
Whilst OBD is supposed to be generic...it isnt always and there can be regional variations hence all UK scan tools may not work correctly if at all. But ideally you'll want more than just fault codes.
stevieturbo said:
Some cheap OBD readers might get you there, but you might need to spend a little more, likes of this, or if there is similar from Ozzie land just in case ( eg EFI Live scan tool etc)
Whilst OBD is supposed to be generic...it isnt always and there can be regional variations hence all UK scan tools may not work correctly if at all. But ideally you'll want more than just fault codes.
I have an EFI Live flash scan tool, with all the wires/connections and everything you’d need (all you’d have to do is licence it to your vin number) that I no longer require......just sayingWhilst OBD is supposed to be generic...it isnt always and there can be regional variations hence all UK scan tools may not work correctly if at all. But ideally you'll want more than just fault codes.
albundy89 said:
Thanks to all replies,I`ll pass this info on.
In fact I`ll see if my Mech can come on here and explain things better as when he starts on about closed loops and + and - voltages I am already lost.
Aitch H I will mail you privately on your offer . Thanks.
At the minute none of those things matter.In fact I`ll see if my Mech can come on here and explain things better as when he starts on about closed loops and + and - voltages I am already lost.
Aitch H I will mail you privately on your offer . Thanks.
Test to see if you can actually see a voltage/reading when you apply one to the relevant ecu input. That will at least prove wiring integrity is good.
Also test to ensure you have 12v and ground applied to the heater of the sensor. 2 easy and cheap/free tests which can help steer you in the right direction.
But as said, there will be multiple codes depending on exactly what the ecu is unhappy with, and as to which sensor/wiring it is unhappy
Just as another point...
Aren't there 4 O2 sensors, 2 pre-cat and 2 post cat? So replacing 2 may not have fixed the problem if it was one of the other 2 that was faulty...?
With the EFI Live reader, you only need the licence to flash an ECU, you can use the reader / cable etc. to read the tune and any codes etc. without having to buy a licence.
Aren't there 4 O2 sensors, 2 pre-cat and 2 post cat? So replacing 2 may not have fixed the problem if it was one of the other 2 that was faulty...?
With the EFI Live reader, you only need the licence to flash an ECU, you can use the reader / cable etc. to read the tune and any codes etc. without having to buy a licence.
Ok, so after a long chat with the garage I have been assured that all the relevant voltage,ground and wiring checks have been carried out and the only code appearing refers to an o2 sensor fault.
I know the bloke has spent a lot of time and effort,one way or another over the last few weeks on this and seems on the point of giving up.
What he has suggested is mapping out the o2 sensors,Is this feasible or indeed possible.
I know the bloke has spent a lot of time and effort,one way or another over the last few weeks on this and seems on the point of giving up.
What he has suggested is mapping out the o2 sensors,Is this feasible or indeed possible.
albundy89 said:
Ok, so after a long chat with the garage I have been assured that all the relevant voltage,ground and wiring checks have been carried out and the only code appearing refers to an o2 sensor fault.
I know the bloke has spent a lot of time and effort,one way or another over the last few weeks on this and seems on the point of giving up.
What he has suggested is mapping out the o2 sensors,Is this feasible or indeed possible.
And again....there will be multiple codes depending on exactly what fault, and as others have said, there can be up to 4 sensors. 2 pre cat and 2 post cat.I know the bloke has spent a lot of time and effort,one way or another over the last few weeks on this and seems on the point of giving up.
What he has suggested is mapping out the o2 sensors,Is this feasible or indeed possible.
Exactly what are the fault codes ? "on o2 sensor fault" is too vague to give any indications as to the problem remotely.
And the cost of removing the o2's via a remap would outweigh the cost of fixing the problem correctly. There is no reason this should have taken much time or effort with a competent mechanic.
But again.....there simply isnt enough accurate information to give a remote diagnosis
Right,so basically as my garage seem stuck on this I need to find a second opinion.
Originally when the fault showed up first I phoned round several garages in Perth,Scotland of course,to be told they didnt have the necessary gear to read the faults.
I tried Peter Vardy Vauxhall dealers in Perth who assured me they could, and they came up with, Faulty o2 sensor, which they offered to replace for the princely sum of 489.00 plus vat. if and when they could source one.
It was then I sourced the necessary from Monkfish and had my local garage fit them.
Incidentally there are only 2. (5.7 vxr)
Anyone out there know of someone, preferably Scotland who could give a second opinion.
Originally when the fault showed up first I phoned round several garages in Perth,Scotland of course,to be told they didnt have the necessary gear to read the faults.
I tried Peter Vardy Vauxhall dealers in Perth who assured me they could, and they came up with, Faulty o2 sensor, which they offered to replace for the princely sum of 489.00 plus vat. if and when they could source one.
It was then I sourced the necessary from Monkfish and had my local garage fit them.
Incidentally there are only 2. (5.7 vxr)
Anyone out there know of someone, preferably Scotland who could give a second opinion.
And I keep saying it "faulty O2 sensor" is too vague.
You've had the car for a while.....so this fault is only recently ? Is there a de-cat or anything ? Any wires hanging underneath as if there should be another pair of sensors after where any cats once were ?
Although I think older cars with the 5.7 may not have had rear sensors ?
Whether via EFILive or the Palmerscan thing, that at least would give you access to fault codes yourself as well as live data so you can see yourself without paying someone at a dealers to try and diagnose....which often is like banging your head against a wall.
And after fitting the new sensor ( which one did they replace ? ) did the fault go away ? Were any codes cleared ?
When does the light come on ? cold, warm, after driving ? Or light on all the time ?
You've had the car for a while.....so this fault is only recently ? Is there a de-cat or anything ? Any wires hanging underneath as if there should be another pair of sensors after where any cats once were ?
Although I think older cars with the 5.7 may not have had rear sensors ?
Whether via EFILive or the Palmerscan thing, that at least would give you access to fault codes yourself as well as live data so you can see yourself without paying someone at a dealers to try and diagnose....which often is like banging your head against a wall.
And after fitting the new sensor ( which one did they replace ? ) did the fault go away ? Were any codes cleared ?
When does the light come on ? cold, warm, after driving ? Or light on all the time ?
Stevie,thanks for your continued patience,both Peter Vardy and my local garage quoted" o2 sensor fault".
Apologies for being so vague but I am only repeating what I have been told by both garages.
Both sensors were replaced at the same time, and still the same fault.
I replaced the cats almost 2 yrs ago,fault first appeared almost 9 months ago
The fault appears after a very short time,sometimes whilst sitting idling on my drive but usually after no more than a mile
Apologies for being so vague but I am only repeating what I have been told by both garages.
Both sensors were replaced at the same time, and still the same fault.
I replaced the cats almost 2 yrs ago,fault first appeared almost 9 months ago
The fault appears after a very short time,sometimes whilst sitting idling on my drive but usually after no more than a mile
Do you have an Android phone or Apple phone?
If Android, get a bluetooth OBD2 reader thing, like this:
https://www.ebay.co.uk/itm/Torque-ELM-327-Bluetoot...
Get the free app 'Torque'. There are some options in the settings to download the GM specific fault codes in addition to standard ones.
https://play.google.com/store/apps/details?id=org....
If iPhone, get a WiFi OBD2 reader thing, like this (this one appears to do both in fact):
https://www.ebay.co.uk/itm/WiFi-OBD2-ELM327-Blueto...
I'm not sure what the best app is, maybe something like this?
https://itunes.apple.com/us/app/obd-auto-doctor/id...
Anyway, that MAY allow you to read the codes. If they're just generic O2 sensor related codes, then you may well be in luck. Off the top of my head I can't remember if Torque could read them.
It doesn't sound like the garage is being very helpful to be honest.
If Android, get a bluetooth OBD2 reader thing, like this:
https://www.ebay.co.uk/itm/Torque-ELM-327-Bluetoot...
Get the free app 'Torque'. There are some options in the settings to download the GM specific fault codes in addition to standard ones.
https://play.google.com/store/apps/details?id=org....
If iPhone, get a WiFi OBD2 reader thing, like this (this one appears to do both in fact):
https://www.ebay.co.uk/itm/WiFi-OBD2-ELM327-Blueto...
I'm not sure what the best app is, maybe something like this?
https://itunes.apple.com/us/app/obd-auto-doctor/id...
Anyway, that MAY allow you to read the codes. If they're just generic O2 sensor related codes, then you may well be in luck. Off the top of my head I can't remember if Torque could read them.
It doesn't sound like the garage is being very helpful to be honest.
albundy89 said:
Stevie,thanks for your continued patience,both Peter Vardy and my local garage quoted" o2 sensor fault".
Apologies for being so vague but I am only repeating what I have been told by both garages.
Both sensors were replaced at the same time, and still the same fault.
I replaced the cats almost 2 yrs ago,fault first appeared almost 9 months ago
The fault appears after a very short time,sometimes whilst sitting idling on my drive but usually after no more than a mile
Fault occurring after a period of time, might imply it is less likely to be a hard wiring fault. Although it could still be wiring or heater related as that would take a little time to determine something isnt right depending on what is wrong.Apologies for being so vague but I am only repeating what I have been told by both garages.
Both sensors were replaced at the same time, and still the same fault.
I replaced the cats almost 2 yrs ago,fault first appeared almost 9 months ago
The fault appears after a very short time,sometimes whilst sitting idling on my drive but usually after no more than a mile
But without spending the time testing various things.....best thing to do is try and get accurate fault codes because there are just too many variables to be guessing.
If you're DIY inclined....Scanner Danner always has great videos, but this is basic stuff a garage should be able to do ( but most are clueless )
https://www.youtube.com/watch?v=uYMGnvtgi8w
https://www.youtube.com/watch?v=uYMGnvtgi8w
SturdyHSV said:
Do you have an Android phone or Apple phone?
If Android, get a bluetooth OBD2 reader thing, like this:
https://www.ebay.co.uk/itm/Torque-ELM-327-Bluetoot...
Get the free app 'Torque'. There are some options in the settings to download the GM specific fault codes in addition to standard ones.
https://play.google.com/store/apps/details?id=org....
If iPhone, get a WiFi OBD2 reader thing, like this (this one appears to do both in fact):
https://www.ebay.co.uk/itm/WiFi-OBD2-ELM327-Blueto...
I'm not sure what the best app is, maybe something like this?
https://itunes.apple.com/us/app/obd-auto-doctor/id...
Anyway, that MAY allow you to read the codes. If they're just generic O2 sensor related codes, then you may well be in luck. Off the top of my head I can't remember if Torque could read them.
It doesn't sound like the garage is being very helpful to be honest.
I have an iPhone and use what looks to be exactly that WiFi OBD2 device and an app called DashCmd. Works a treat and reads all the engine fault codes no problem.If Android, get a bluetooth OBD2 reader thing, like this:
https://www.ebay.co.uk/itm/Torque-ELM-327-Bluetoot...
Get the free app 'Torque'. There are some options in the settings to download the GM specific fault codes in addition to standard ones.
https://play.google.com/store/apps/details?id=org....
If iPhone, get a WiFi OBD2 reader thing, like this (this one appears to do both in fact):
https://www.ebay.co.uk/itm/WiFi-OBD2-ELM327-Blueto...
I'm not sure what the best app is, maybe something like this?
https://itunes.apple.com/us/app/obd-auto-doctor/id...
Anyway, that MAY allow you to read the codes. If they're just generic O2 sensor related codes, then you may well be in luck. Off the top of my head I can't remember if Torque could read them.
It doesn't sound like the garage is being very helpful to be honest.
Phil
Gassing Station | HSV & Monaro | Top of Page | What's New | My Stuff