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Check engine light code 12.
Posted: Wed Apr 01, 2015 2:56 pm
by bill
My check engine light has started to come on randomly after driving for a while. Done the paperclip test and got error 12 EXHAUST GAS RECIRCULATION SYSTEM (EGR). Could this have anything to do with fitting an aftermarket exhaust and decat? Ive had the exhaust fitted for about 2months and today is the first time ive had the check engine light.
Posted: Wed Apr 01, 2015 3:02 pm
by Merlin
Your EGR valve is next to the head and intake manifold. It is most likely blocked with carbon and needs a clean. There should be a writeup on how to clean it. I'll have a look.
It doesn't have anything to do with your exhaust.
Edit - See what Mart did here -
http://www.ludegeneration.co.uk/post15230.html
Posted: Wed Apr 01, 2015 3:14 pm
by bill
Thanks for that. I think I've found a link but it's to another site so not sure if it's the same one. Will driving the car do it any damage in the meantime?
Posted: Wed Apr 01, 2015 3:15 pm
by bill
Just saw ur update I'll have a look now cheers dude.
Posted: Wed Apr 01, 2015 3:16 pm
by Merlin
No it shouldn't do damage in the short term. The function of the EGR is to reduce NOx gasses, benefiting emissions at idle/part throttle, and it helps reduce peak cylinder temps.
Posted: Wed Apr 01, 2015 3:26 pm
by bill
Cool I'll have a read through that and give it a bash and see if that fixes the problem.
Posted: Wed Apr 01, 2015 4:26 pm
by ADS1
Can also be a loose connection at the egr plug. I had code 12, even though I had cleaned egr valve about a year before, when I removed it, you could eat your dinner out of it!!! Turned out to be faulty connection.

Posted: Wed Apr 01, 2015 6:04 pm
by bill
Daft question time but what tool is best for getting the bolts undone? I can't get a ratchet or spanner anywhere near those bolts
Posted: Wed Apr 01, 2015 6:52 pm
by clarelude23
If you remove your intake piping it should make things easier. I cracked mine with a spanner first then a quarter inch ratchet with extension and universal joint.
Posted: Wed Apr 01, 2015 7:23 pm
by ADS1
Ideally, you want one of those very thin ratchet extension bars, and a good socket, I used non slip ones. There is one bolt, I can't remember which one, but you can't get the socket suare on, but a thin bar helps.