Audi A4 CGLC limp mode

   #21  

Jack@European_Parts

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Little update...

I did a bit digging today. had a wiggle of all the connectors on the voltage B side of the loom.

Unplugged the EGR valve and never threw a code (probably because the EGR has been mapped out due to previous issue) On the off chance I plugged it back in and the car dropped into limp mode. It did this a couple of times. ive left it unplugged for now and going to run the car over a few days to see if fault crops back up.

The crank sensor i think was just a false positive lead. If the 5V line has dropped down, then chances are the crank sensor has seen a significant drop in voltage to stop it from sending signal, hence why the ECU threw that code up in the scan. Cleared it off and it hasnt come back up 'yet' so probably nothing wrong with the sensor (otherwise it would more than likely happen all the time)

Ill run the car a few days and see what comes up. Hopefully unplugging the EGR sorts the issue out.

Does anyone know if the EGR is prone to condensing up with water inside the little black cap on the top of it? Heard someone mention they were pretty prone to it.


More FOD and finally admittedly for EGR "ass to mouth deletes", can't blame anyone for not wanting to do that, huh?

Thank you for confirming this suspicion.


FOD WINS!


 
   #22  

carsey

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I think it’s just poor quality that’s caused it to fail. Second time it’s three issues up relating to the EGR valve.

Don’t think anything has got inside of it or whatever, it’s just failed electronically.

I did mention it had the EGR deleted in my initial post?
 
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carsey

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Im slightly confused....what foreign object caused an electrical issue on a sealed unit?

Far from taking the cover off to see if theres any green solder joints in there, then there isnt really any chance of foreign object damage.
 
   #25  

Jack@European_Parts

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Im slightly confused....what foreign object caused an electrical issue on a sealed unit?

Far from taking the cover off to see if theres any green solder joints in there, then there isnt really any chance of foreign object damage.

You didn't have a fault for the EGR & due to being ignored by FOD programming, this my point and why FOD must be also rooted out, do you see now?

 
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carsey

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What if it was failure of electric components inside the EGR?
 
   #27  

Jack@European_Parts

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What if it was failure of electric components inside the EGR?




I think you are missing the point huh and that the ECU "ultimately" looks & posts or doesn't post needed diagnostic dictionary data needed as programmed when manipulated & regardless of the condition of the actual component, how do you think the tuners and VAG do or did with what they purported in Diesel-Gate?
 
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carsey

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You lost me but hey.....see how leaving it unplugged goes.
 
   #29  

carsey

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Update: leaving it unplugged seems to have cured the issue.

So to recap for anyone having future issues.

EGR initially failed a few years ago putting car in limp mode - EGR mapped out and blanked before the inlet
Few years later - electronic side of the EGR started to play up and throw voltage reference B open circuit error
Scan also threw up false positive of the crank sensor having no signal.
Did bit of leg work and unplugged sensors on the voltage B rail - didnt get chance to monitor voltage as found issue straight away with the EGR
Unplugged the EGR valve to stop the faulty circuit and the fault has stopped and car no longer drops into limp mode.

Next solution from now is to get the EGR removed and the coolant pipes joined back together with the flanges on manifolds blanked off.
 
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