Check engine / Emissions light

[Simon PMB]

Hi and happy new year to everyone.

I have a 2007 3.2 petrol and have an issue with the amber engine / emissions light coming on.

Back in September, shortly after buying the car, the emissions warning light started coming on intermittently, although the car drove fine and there were no other warning or messages. I ended up replacing the sealing ring on the fuel cap, as the original was quite worn and this then seemed to cure the problem.

In November I had a major service completed at a very well regarded Volvo specialist and asked them to check what had caused the light to come on, but there were no historic codes stored relating to the previous problems and no faults evident with the EVAP system etc.

Since September the light has not come on again, until yesterday when it appeared again. I am not sure if it is related, but it came on after I had completed 4 very short journeys in quick succession. As before, the car drives fine and there are no other warnings or messages.

I have driven the car again today and the light is still on.

Any thoughts as to what might have caused this warning light to reappear again? The Volvo Indy is some distance from me and it will be some time before I can take the car to them, by which time the light may have gone out again!

Many thanks

[SwissXC90]

It can be any one of 1000 problems.

You need to read the codes to find out more info.

[Simon PMB]

Just a quick update. I drove the car again yesterday and the warning light went off after a while and has stayed off since.

I definitely agree that it needs to be plugged into Vida to see what causes the light to come on, but being intermittent this isn't going to be easy.

When the car was serviced in November (with no warning light having been on since September) even using fully up to date Vida software there were no historic codes stored, so I suspect it will be the same this time.

Just wondered if anyone else has had a similar experience or has any ideas?

[SwissXC90]

It's pretty easy.

Historical problems are stored in the memory, even when the Check Engine warning light is turned off.

Connect VIDA, read all codes, see what it says.

Study and understand the codes, check the operating parameters (odometer, engine speed, outside temperature, etc) to determine which was the most recent issue.

Print them all out.

Then clear them, and go from there.

[Zebster]

You don't need anything special to read car 'powertrain' Diagnostic Trouble Codes (I've long relied upon a cheap ELM327 Bluetooth OBD2 adaptor in conjunction with the free 'Car Scanner' app on my Android phone and never once missed having the full VIDA setup) so why not get your own and - if necessary - drive around with it connected so you can read the code while the warning light is on? However as @SwissXC90 points out, historic DTCs should be stored until actively deleted.