Egr valve / now engine management ?

**steveo273** · 12th November 2010, 20:11

Hi all,

Firtsly great site and great info ( very helpful )
Right here we go..for some time now spanner light been coming on for say a month with no difference in power,would only stay on for 5 mins then go off..anyway for the last week car has been flat power wise and wouldnt go until 2000rpms then if was off like normal.Anyway after looking on the site and reading alot on the egr valve i decided to take it off and clean ( also replaced fuel filter ) Anyway car now runs well again so great info.
Dont know if spanner light back on yet as hasnt been stood long enough to see ( only came on when cold or left for hours)
Anyway MAIN QUESTION IS..i took leads off battery to try and clear that spanner light? left off for over an hour, sine then i now have ENGINE MANAGEMENT LIGHT ON?
Any input or ideas lads?
Thanks for any advice.
Steve

**steveo273** · 12th November 2010, 20:42

Anybody?

**markj23** · 12th November 2010, 22:07

im sure the diesel boy will enlighten you shortly but welcome anyway

**felixx** · 12th November 2010, 22:17

Originally Posted by steveo273

Anybody?

When the EGR valve throws up a problem,the fault code is PO400,if the problem is not rectified,(like when you blank it off),the spanner light is replaced by the engine management light.This will go out after a set amount of "start up's"etc,).If you have,or can get hold of, a code reader,check the codes,then erase them.This should turn out the engine light,unless there is another problem,however what you have described is just what you would expect after an EGR "issue".FELIXX.

**mparks8590** · 12th November 2010, 22:23

hi

at first guess it could be one of several things

1) glow plugs .....that tends to cause a short illumination of lamp that then goes after a few minutes. you can remove and test each one if you don't want to replace but at about £40 a set coming into winter, i'd be replacing anyway every 3 years as a maintenance issue

2) egr is most likely bet. strip, clean and replace as per how 2. make sure gaskets are cleaned or bette still replaced.....make sure you clean the intake where egr attaches to manifold trying not to drop carbon deposits into inlet. use carb cleaner and soft toothbrush. strip solenoid, clean and rebuild using wd40 , white lithium grease spray as lubricant

3) clean boost ( map ) sensor.... carb cleaner and soft toothbrush

4) clean maf sensor ----pure alcohol

after that you should be in a better place. for the price of £10 ( two cans of carb cleaner) you should eradicate the lights you mention.

whilst there do a oil / air filter change and notice the difference

any questions let us know

**steveo273** · 18th November 2010, 22:00

Hi Felix and Mparks,
Firstly i did take egr valve off and clean it and that fixed my main problem which was not pull beneath 2000rpm..car seems to run fine now..
My problem was i use to get spanner light on just when car was cold but did go off after 5 mins..would only come on when cold..anyway after i took egr valve off and cleaned it ran well... So i read on here that if i disconnected battery for an hour it would clear the spanner light ( which it has ) BUT now engine manange ment light is on..been on a week now, So im hoping that after so many starts it goes off ? could that happen?
Dont think its any other reason as car seems spot on. And yes just replaced fuel filter,oil filter and air filter and oil etc..
Cheers
Steve

PS great useful site ;-)

**felixx** · 18th November 2010, 22:32

Originally Posted by steveo273

Hi Felix and Mparks,
Firstly i did take egr valve off and clean it and that fixed my main problem which was not pull beneath 2000rpm..car seems to run fine now..
My problem was i use to get spanner light on just when car was cold but did go off after 5 mins..would only come on when cold..anyway after i took egr valve off and cleaned it ran well... So i read on here that if i disconnected battery for an hour it would clear the spanner light ( which it has ) BUT now engine manange ment light is on..been on a week now, So im hoping that after so many starts it goes off ? could that happen?
Dont think its any other reason as car seems spot on. And yes just replaced fuel filter,oil filter and air filter and oil etc..
Cheers
Steve

PS great useful site ;-)

Yes.It should go off.....eventually!!,that is unless there is an underlying problem,(which I don't think there is).If you have access to a code reader you could erase it without any problems,and then,if you had another problem,the spanner light would come on like it did in the first place.FELIXX.

**felixx** · 18th November 2010, 22:37

Originally Posted by felixx

Yes.It should go off.....eventually!!,that is unless there is an underlying problem,(which I don't think there is).If you have access to a code reader you could erase it without any problems,and then,if you had another problem,the spanner light would come on like it did in the first place.FELIXX.

Forgot to add,some of the other members on here have left their battery disconnected overnight to erase the EML.I'm sure someone could give you advice in that direction,although it shouldn't do any harm other than leave you without your alarm system.FELIXX.

**Dazzy2006** · 18th November 2010, 22:39

Originally Posted by steveo273

Hi Felix and Mparks,
Firstly i did take egr valve off and clean it and that fixed my main problem which was not pull beneath 2000rpm..car seems to run fine now..
My problem was i use to get spanner light on just when car was cold but did go off after 5 mins..would only come on when cold..anyway after i took egr valve off and cleaned it ran well... So i read on here that if i disconnected battery for an hour it would clear the spanner light ( which it has ) BUT now engine manange ment light is on..been on a week now, So im hoping that after so many starts it goes off ? could that happen?
Dont think its any other reason as car seems spot on. And yes just replaced fuel filter,oil filter and air filter and oil etc..
Cheers
Steve

PS great useful site ;-)

Usually if u get a spanner light on cold start ups and it goes off soon after you have a duff glowplug

**GazVXLINE170** · 18th November 2010, 22:41

First of all don't go near the MAF m8 - yet anyway - you may create another issue. They are very fragile and if you break it you are looking at £100+ to rectify.

Looking at the facts you took the EGR valve off, cleaned and replaced and also changed the Fuel filter. One of these I would say is either not electrically connected properly (wouldn't surprise me if the EGR valve isn't). Check all electrical connections first.

The engine management light is the the spanner light m8, I assume you are talking about the little yellow engine symbol - as that is the emissions light. So I say give the EGR area a check and make sure it is sealed too - gaskets etc and get the codes read. If the EGR valve is not the problem, then I would look at the MAF, as faulty ones will usually cause the emissions light to come on.

Disconnecting the battery returns the ECU so factory settings - ie it forgets what it learned - ie the way you drive and what the different sensors are reporting back.

Gazza4