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coco
May 21st, 2015, 15:06
Hi guys,

My RS6 encounters another problem.
Rough idling (sometimes even stalls) and misfires on all 8 cylinders over 2500rpm and has no power at all.
It's in the AUDI dealer here in Japan but they couldn't find the cause yet.

They gave me the error codes (I7m not sure if it's the same Vag-Com you guys are using but I list the codes:
・17473 ・17538 ・17536 ・16690 ・16684 ・16687 ・16685 ・16686 ・16689

Can anybody give me the clue?

Please help.

Best regards,
Coco

s8prtotype
May 21st, 2015, 15:30
Missing on all 8 is scary but you could pull the valve covers and check the upper timing guides, easiest way is the drivers side first.

ben916
May 21st, 2015, 18:31
what about the speed sensors on the control arms?

coco
May 22nd, 2015, 00:12
Missing on all 8 is scary but you could pull the valve covers and check the upper timing guides, easiest way is the drivers side first.

Thanks for the quick reply, s8prototype,

I will check with the mechanic.

Coco

coco
May 22nd, 2015, 00:13
what about the speed sensors on the control arms?

Thanks you Ben,

I will inform the the mechanic who're working on my car.

Coco

Dmb408
May 22nd, 2015, 13:50
All these idling issues like this, I say suction jet pump, just because it fails so often.

tightgroup
May 23rd, 2015, 03:49
what is a suction jet pump ?? In College there was a girl ... but I digress

Dmb408
May 23rd, 2015, 13:40
Part of the vacuum system. It sits under the manifold.

G2
May 23rd, 2015, 19:10
The codes are just a snapshot in time (I did not look them up, general info here), and most are inferred or extrapolated based on out of range values.
Briefly: Had a A5 2.0T with something like 15 codes recently. Similar issues.
Had a major vacuum leak. Fixed. Ran perfect again. Other shops couldn't figure it out...customer was going to sell the car due to frustrations.

If symptoms are sudden, unlikely to be tensioner related on both banks. Of course the oil is changed every 5K miles or less....ahem.

Lack of fuel pressure will cause similar drivability issues. Especially at medium revs and higher loads. If the engine will rev higher in neutral under no load, but can't rev quickly during snap-throttle, would lean towards the fuel system. Last fuel filter replacement?

Need to look at Live Data in whatever scanner they have, and view 02 values along with MAP and other values that may be out of normal range. A good tech should be able to glean this data in short order and ascertain where to start looking. Especially with a Fuel Pressure Gauge hooked up.

Keep us posted.

Aronis
May 23rd, 2015, 21:33
I asked my indy about the Suction Jet Pump, he said he can see mine on the back side and is reachable without removing the manifold. I did not have time to have him show me since the book says its under the manifold. Who designs these thing? :)

Mike

rs6BC
May 29th, 2015, 00:05
Removed the manifold for mine.. Great if it doesn't need to be

A4V8swap
May 30th, 2015, 20:42
There absolutely no way to remove the jet suction pump without pulling the intake manifold. I just did it. I don't know what he is looking at either because you can't even see it without pulling the intake.

A4V8swap
May 30th, 2015, 20:49
Not only that. My jet suction pump I had full power, no engine lights and just no brake booster vacuum so it was hard to press the brakes. That was all, and it was split in half too.

Nate Dog
December 21st, 2016, 12:46
Not only that. My jet suction pump I had full power, no engine lights and just no brake booster vacuum so it was hard to press the brakes. That was all, and it was split in half too.

Hey V8 Swap, this is exactly the issue I have, no brake assist with vacuum, no codes & very rough idle to the point of stalling when cold. I have started taking things apart, have got all bolts out of the top of intake manifold but bolts through throttle body look very difficult to get out. Have got front bumper off but not sure exactly how to access throttle bolts. Anyway what exactly was your fault/cause and what was fixed or replaced?

DHall1
December 21st, 2016, 16:45
Place the front carrier in service position.

Then em you can get to the tbody bolts.

be careful taking intake off. It's not the easiest task

replace or bypass after run pump while your in there.

Bigglezworth
December 22nd, 2016, 06:52
Hi guys,

My RS6 encounters another problem.
Rough idling (sometimes even stalls) and misfires on all 8 cylinders over 2500rpm and has no power at all.
It's in the AUDI dealer here in Japan but they couldn't find the cause yet.

They gave me the error codes (I7m not sure if it's the same Vag-Com you guys are using but I list the codes:
・17473 ・17538 ・17536 ・16690 ・16684 ・16687 ・16685 ・16686 ・16689

Can anybody give me the clue?

Please help.

Best regards,
Coco

Spray some MAF sensor cleaner down under the intake in the area just behind the PCV valve. If the engine speeds up - it's your suction pump. Solid day's worth of work to repair. I moved my SAJ to the firewall after it failed. Not subject to the intense engine heat there that is the leading cause for failure in the first instance. Stupid design IMO.