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A Query for those technical out there
Posted: Fri Aug 12, 2011 3:03 pm
by P_G
Unfortunately I have experienced my first major problem with the RS today in 4 years on ownership. Took it out today for a run at lunchtime as it hadn't been used since Monday and when warming up felt a slight misfire but went as the revs invcreased. Drove for another 20 or so miles with no issues through the entire rev range but then had to stop for petrol.
After starting up again I drove down to the first roundabout and the engine cut out. Odd. So started up again and coasting at low revs the engine cuts again. Then starting it the third time and there is a distinct misfire and it progressively gets worse. Pull over to do a
VCDS scan on the car and sure enough multiple misfires detected code and then lists cylinder 1 and 5. Decide that since I'm only a mile or so away from Tyneside Audi I'll take it there misfiring away and cutting out every time under 1500rpm i.e coming to a junction. When I get there it cuts out again and another scan shows misfires on cylinders 5,1 3 and 2 and the IM runner flaps are both implausible signals. Start it up again and it is misfiring horribly and hunting for 10-15 seconds or so at idle and then cuts out. Of course EML flashing and EPC on
So it is now sitting at Tyneside awaiting inspection.
Any ideas? Could damaged lambda sensors cause such misfiring. I only ask as I cleaned the full underside of the car at the weekend with a pressure washer except of course the engine bay.
Re: A Query for those technical out there
Posted: Fri Aug 12, 2011 3:38 pm
by Doug_S2
Sounds like a vacuum leak off the inlet manifold so it sucks in too much air and cannot make it idle.
Re: A Query for those technical out there
Posted: Fri Aug 12, 2011 3:46 pm
by sonny
Hope its a easy and simple fix.
Re: A Query for those technical out there
Posted: Fri Aug 12, 2011 3:50 pm
by P_G
Would that cause misfiring as well Doug?
The codes were;
Right Engine Solenoid Valve (N145): Open Circuit
P1577 - 004 - No signal / communication - Intermittent
000768 - Random / Multiple Cylinder Misfire Detected
P0300 - 001 - Upper Limit Exceeded
000769 - Cylinder 1: Misfire detected
P0301 - 001 - Upper Limit Exceeded
That was the first scan, I didn't get a chance to log the second scan.
Re: A Query for those technical out there
Posted: Fri Aug 12, 2011 3:58 pm
by Doug_S2
it would cause misfires as well
Re: A Query for those technical out there
Posted: Fri Aug 12, 2011 4:05 pm
by P_G
Thanks, let's see what the masterminds at Audi come up with.....
Re: A Query for those technical out there
Posted: Fri Aug 12, 2011 4:25 pm
by RSKiwi
P_G wrote:Thanks, let's see what the masterminds at Audi come up with.....
My money is on
'No problem sir we have changed your washer fluid and rear wheel TPMS sensor its all fixed' ....followed by cheesy grin and their hand out for £923.36
Youd drive out the gate with the car in exactly the same shape as when it went in.....
Spot the person who has been burnt by Audi before?!!

Re: A Query for those technical out there
Posted: Fri Aug 12, 2011 4:29 pm
by P_G
They know me better than to do that, I must be one of their 'loyal but pain in the ass' customers.

Re: A Query for those technical out there
Posted: Fri Aug 12, 2011 4:53 pm
by Timster
RSKiwi wrote:P_G wrote:Thanks, let's see what the masterminds at Audi come up with.....
My money is on
'No problem sir we have changed your washer fluid and rear wheel TPMS sensor its all fixed' ....followed by cheesy grin and their hand out for £923.36
Youd drive out the gate with the car in exactly the same shape as when it went in.....
Spot the person who has been burnt by Audi before?!!

lol... yeah. I bet the first time you come to use the washers... they're empty !
Re: A Query for those technical out there
Posted: Fri Aug 12, 2011 5:18 pm
by Revolution
any news on what it is......?
Re: A Query for those technical out there
Posted: Fri Aug 12, 2011 5:26 pm
by P_G
My source on the inside says the master techs are looking at it now.
Re: A Query for those technical out there
Posted: Fri Aug 12, 2011 5:31 pm
by Revolution
fingers crossed for you...
Re: A Query for those technical out there
Posted: Fri Aug 12, 2011 5:39 pm
by Revolution
Have you heard anything yet?
Re: A Query for those technical out there
Posted: Fri Aug 12, 2011 5:42 pm
by adsgreen
Agree with doug on this.
I did some vacuum system testing as per the tech bulletin. Once finished I just started the car (as opposed to ignition key out) so for a split second there was no vacuum.
By god did the car complain - multiple misfires, manifold flap codes, flashing MIL and EPC lights on.
I shut off the car (after a big "oh feck I've broken it" moment) double checked the connections I'd used to manually test, and then restarted from cold after clearing all the fault codes. Everything back to normal and never troubled me again.
So yes, does sound like the connection/valve under the inlet manifold has gone or there is some other big vac loss somewhere . However as per the TSB you can test this without taking the manifold off - just disconnect or T the various vac lines and see what pressure it attains and what it's holding. Even easier if you use a hand vacuum pump to test. Shouldn't be no more than an hour (probably less) to diagnose if the IM has to come off.
Re: A Query for those technical out there
Posted: Fri Aug 12, 2011 5:51 pm
by P_G
Hopefully Audi's mastertechs are as insightful. Just seems odd that after a good few weeks it catastrophically lets go like that?