Omega Owners Forum
Omega Help Area => Omega General Help => Topic started by: CBH on 19 July 2008, 15:46:51
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Hi
Major problem driving home thursday night from work
did 15 miles all was ok
then loss of power, car got slower and slower and the engine stopped.
pulled into the side of the road.
Engine re-started first turn of the key.
pull off again and drove the last 20 miles home.
during this the car losses power and slows down, but the engine did not stop again, I had to pull over 3 more times, turn the engine off and then re-start.
At no time did the EML come on or stay on.
Just done the paperclip test and the only code displayed was 129
EGR valve feedback voltage low.
Could this be the problem or is there something else going on?
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egr valve if disconnected on my 3.0 V6 will cut the engine out! cheap to fix get an egr valve from a scrappy £10 - £20 ish instead of £100 at vauxhall very very easy to change on the v6 about the easiest v6 job todo!
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I take it you have checked wiring and connections ?
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worth flushing out with carb cleaner first? :-/ you never know :-/. but isnt that elecrical prob if light cones on???
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Just check the plug and wiring looks ok
It's a 5 pin plug and there are two parts to this unit
A solenoid on pins A & E
and a variable resistor on pins B,D &C (wiper on C)
can anyone tell me what the resistance reading should be between the pins.
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Try blanking off the EGR valve. Its a recommended mod, did it to my car a year ago and haven't noticed any detrimental effects.
Alan
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why would the egr be there if performance were improved by removing it? :-/
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Decreases Oxides of Nitrogen (NOx) Emissions.
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why would the egr be there if performance were improved by removing it? :-/
Virtually all engines are now built for emissions, not performance ;)
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if its bust blanking it off wont make any difference the only time blanking them off is any use is when there castings crack and they start blowing that is when a performance increase is noted because there aint a hole in the exhaust anymore!!!!!!!!!!!!!!!!!
you will require a replacement unit unfortunatly as i reckon its a sealed unit if it isnt then someone please enlighten me!
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if its bust blanking it off wont make any difference the only time blanking them off is any use is when there castings crack and they start blowing that is when a performance increase is noted because there aint a hole in the exhaust anymore!!!!!!!!!!!!!!!!!
you will require a replacement unit unfortunatly as i reckon its a sealed unit if it isnt then someone please enlighten me!
Blocking off a stuck open one will obviously help with engine running. Blocking a working one will improve engine response when cruising, at the expense of a marginal decrease in mpg (marginal, as petrols do not make big use of egr like diesels do)
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but if its stuck open wont it light up the eml? and cut the enine out?
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but if its stuck open wont it light up the eml? and cut the enine out?
Depends how far open its suck, and whether the feedback is still connected
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When you say block it off, I assume you put a plate between the EGR and the mounting but leave the valve connected so the ECU thinks it still there.
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When you say block it off, I assume you put a plate between the EGR and the mounting but leave the valve connected so the ECU thinks it still there.
That's exactly what you do.
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I have measured the EGR and found it's a problem with the valve position output. between pins C & D (the resistance is too high).
But I always come back to ,would this fault course the problem described at the beginning of my thread???
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an old coke can or similar is perfect for the job. :y
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an old coke can or similar is perfect for the job. :y
is there a guide for blanking off - i'm sure i've read something before but search for EGR found nothing?
Coke can as blanking piece between where and where? hermatite sealant? :-/
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Dave Kember did an article for the ABS magazine on this, using my car for illustration, but I need my other laptop to get pics so the short version is:
1. Undo the two EGR valve retaining bolts and remove the valve.
2. Take the metal gasket and trace around it on a sheet of suitable metal (a coke can will do).
3. Cut out the traced shape and make two holes for the retaining bolts. Don't make any other holes, this is a blanking plate!
Refit the EGR valve with the blanking plate sandwiched between two new metal gaskets.
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if the egr is feeding back an unlikely value to ecu (eg, stuck open/closed), ecu will try to limp mode it. If you have electric issue with it, it needs replacing. If its stuck open, paint stripper may help.
blanking off helps if its blowing.
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Thanks The Boy
I will change the EGR as there is an electrical problem with it,
Your posting was the one I wanted, as it explained the fault mechanism that caused the symptons I was getting.
As an engineer I hate "poke and hope" method of fault finding and just wanted to know why it was wrong.
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Indeed - I would try a replacement from a scrappy.
Blanking off is completely misleading for this problem IMHO.