North Bay Pressure Test for B6 A4 Vacuum System?

[chrisdeaner]

I've got a 2003 A4 that's having some issues with the vacuum system. Unfortunately I don't have an air compressor to do the vacuum test outlined in a4darkness' Engine Strengthening Thread. If anyone has the equipment for this in the North Bay area I'd happily trade some cold adult beverages for their time to run this through my car so I can figure out what all needs to be replaced.

[a4darkness]

What's the issue Chris? If we can't get you sorted online there's a few fellas in your immediate area who'll be able to help out.

[chrisdeaner]

What's the issue Chris? If we can't get you sorted online there's a few fellas in your immediate area who'll be able to help out.

Wow I wasn't expecting the master himself to show up! So I was having CEL issues with an assortment of codes that aligned with vacuum leak issues and the repeated oil pressure warning while coasting/under vacuum after driving for about 40min or more and finally the car basically died on the freeway. Took it to a local shop that found it was a combination of the Coil Pack Harness wires falling apart and a leak at the suction pump. Once all that was replaced it was running great for about 6 months until I started getting a CEL again with similar codes (I can pull them this weekend when I'm home). I'm 95% sure it's a downstream issue now that the first leak was fixed. Ideally I'd pull it all out similar to how you did your rebuild but I won't have enough time (I use the car weekly to get to the airport for work) so hoping I can pinpoint the issue.

[a4darkness]

Chris for starters it would help to get some pics around your engine bay. Might be able to see an issue but in reality this is something that might need to be examined in person. The tricky thing is that codes are the end result of whatever's happening. So the correlation might not quite be so direct. That said, take some pics around the engine bay so we can start getting a good idea of what we're looking at and post them here. Then pull your codes this weekend and we'll go from there. I would imagine your PCV system is compromised and you've got some vac lines + check valve that need to be swapped... pretty standard stuff. No worries man, we'll get you sorted.

[chrisdeaner]

Will do! FYI I did replace the PRV valve probably about a year ago. Let me get some pics and latest code pull on Friday and get back to you.

Edit: Meant PRV valve. Also here is a thread with some of the codes I was getting prior to having the suction pump replaced. I have a feeling the codes will be similar this time but will report back on Friday.

[a4darkness]

I still get those mixed up...for reference, PRV aka Pancake / Puck = back of the head, PCV = under the intake manifold.
That thread provides some good background info, glad to see Old Guy was dropping knowledge.
Those codes could be caused by a multitude of things. While they can point you in the right direction they're hardly a precise gauge.
The short answer here could be that 034 kit. If your crankcase breather system is original, rather than attempting to patch it it's overwhelmingly easier to yank the whole thing and install the 034 kit.
Yeah, post lots of pics and pull codes. Perhaps take a look at the Engine Strengthening thread before you shoot pics to see what parts in the different areas of concern can be failing. We'll take it from there.

[chrisdeaner]

Ok, had to leave the car at my in-laws last weekend but got a chance to pull the codes and take pics today. The ABS one is new - I'll have to do some research on it. I also need to lookup some of these other ones as they're also not aligning to what I saw before. The symptoms are still the same - car runs fine except for the occasional "shimmy" while idleing at a stoplight. Also every once in awhile the idle gets a little rough at a stop but then next stoplight it runs fine. After 30-45min of normal driving the oil pressure warning comes on when off the gas and in vacuum but then goes away once on the throttle and under pressure again. Happy to provide any other info/pics, just let me know and as always, appreciate the help!

Chassis Type: 8E - Audi A4 B6
Scan: 01,02,03,08,09,0F,11,15,16,17,18,36,37,45,46,55,56 ,57,65,67,69,75,76,77

-------------------------------------------------------------------------------
Address 01: Engine Labels: Redir Fail!
Controller: 8E0 909 518 AF
Component: 1.8L R4/5VT G 0002
Coding: 0016751
Shop #: WSC 63351
VCID: 749B5FD357A3
5 Faults Found:
17544 - Fuel Trim: Bank 1 (Add): System too Lean
P1136 - 001 - Upper Limit Exceeded
17978 - Shareware Version. To Decode all DTCs
P1570 - 008 - Please Register/Activate - Intermittent
16684 - Shareware Version. To Decode all DTCs
P0300 - 001 - Please Register/Activate - Intermittent
16687 - Cylinder 3: Misfire Detected
P0303 - 001 - Upper Limit Exceeded - Intermittent
16688 - Shareware Version. To Decode all DTCs
P0304 - 001 - Please Register/Activate - Intermittent
Readiness: 0000 1000

-------------------------------------------------------------------------------
Address 02: Auto Trans Labels: 01V-927-156.LBL
Controller: 8E0 927 156 P
Component: AG5 01V 1.8l5VT USA 0910
Coding: 0001002
Shop #: WSC 63351
VCID: 3B09B4EF3A7D
No fault code found.

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 8E0-614-517.LBL
Controller: 8E0 614 517 H
Component: ABS/ESP allrad 2328
Coding: 04277
Shop #: WSC 06435
VCID: 2D2D8AB7F409
1 Fault Found:
01119 - Gear Recognition Signal
35-10 - - - Intermittent

Pics:

This has the suction pump that was replaced:



This has the PRV I replaced (prior to the suction pump):



One of the two rubber angle connectors at the bottom here was cracked (before PRV and Suction replacement) so I replaced both:



To the right of the PRV valve:



Throttle Body is on the left:



Close up of hoses left and under the throttle body. When I was getting it smogged last year and it kept throwing codes the smog tech thought this three way connector could be the issue and put the brass one in. I added the worm clamps to be sure it wasn't leaking around the connector:



More around throttle body:



Zoom out of the right side of PRV valve:



Probably nothing important here (my windshield washer pump died the other day but haven't had a chance to order one/deal with taking everything apart to get to it):

[a4darkness]

Chris for starters there's a big crack in your dipstick tube. That can actually cause issues as it's pressurized. You'll need to replace it.
http://www.audizine.com/forum/showth...ck-Replacement

Overall it looks pretty good in there, lots of new hoses. Nice work, especially with the new worm-drive clamps.

Perhaps get new check valves. Those black/white ones are likely from the factory and in need of replacement.
If you are still rocking any OEM braided vac line, swap that out too.

While the OEM one-time clamps might be incredibly difficult to remove, over time they create a poor seal.
Try to rotate hoses and see if they slide around or even free. Might be surprising what you find.

You might want to start putting some (bare) hands on the different rubberized / plastic vacuum parts in the engine bay to see if they've degraded or not.

For example, back of the engine bay (driver's side) there's a firm, curved hose that the that runs to the master cylinder.
At the firewall it attaches to a rubber piece about an inch in diameter. Once mine completely sheared off leaving me stranded in SF. Had to fab something using spare parts in the trunk.
Point being, it was easy to see it was failing by pulling / stretching it a bit. Please be careful when you do this... it's not uncommon for parts to disintegrate in your hands. :-/

Also, *carefully* inspect the wiring that goes to the MAF sensor (dead center here).
While it doesn't necessarily sound like a current issue, considering the state of your coil pack harness wires, it might be next on the list. Fuel injector wiring as well. If it's crispy, don't force it!

Keep us posted and we'll go from there.

[chrisdeaner]

Chris for starters there's a big crack in your dipstick tube. That can actually cause issues as it's pressurized. You'll need to replace it.
http://www.audizine.com/forum/showth...ck-Replacement

Oh crap - I just re-read your reply and saw this and checked the pictures...I actually just replaced that not too long ago (thinking it may have been cracked and causing the pressure issues...guess the replacement wasn't that great of quality. I'll definitely be ordering one of these up along with some check valves per your other recommendations. I should have some time this weekend to do some work on this and will post results. Thanks!

[a4darkness]

Sure thing, keep us posted.

[chrisdeaner]

OK so finally got around to some of this. Replaced the dipstick tube although I'm not convinced mine was completely cracked - it may have just been some residual oil from something else but went ahead and did it regardless. I also replaced the check valves with US plastics for #s 5 and 6 in this thread. I went to replace #1 as well however when I did I found the US Plastics valve wouldn't span the gap between the two hoses as both are fixed in place on either side. Did you extend one of these hoses to bridge it? Anyway when pulling the OEM valve out I found the white side had complete cracked off into the hose so had to pull the piece out with needle nose pliers and ended up replacing it with one of the OEM valves from 5 or 6 for the time being. I didn't have time to brave the other 3 and with the cracked #1 valve I wanted to see the results. I haven't been able to go for a drive yet but will do that this week and post results.

So quick edit - I looked through the main thread some more and found this post which at the very end has a picture that appears to be how #1 was handled. Just checking on what type of hose you used (as you had mentioned heater hose wasn't always a good fit), especially with the 90 degree bend.

Also you had mentioned the coil pack and injector wires - both of those were replaced when the car went kaput on the freeway. They replaced the suction pump first and when I went to pick it up it wouldn't turn over and, as I thought the coil pack wires had finally gone so the shop I had been towed to went ahead and replaced those as well and the guy is familiar with these engines so he did the injector wires at the same time so those are off the list for now.

FYI after I cleared the codes last time the CEL came back (as expected) but with some slight variations. I pulled these after doing the above work and then cleared them to see what comes up next:

VCDS-Lite Version: Release 1.2
Sunday, 07 August 2016, 13:28:42.


Chassis Type: 8E - Audi A4 B6
Scan: 01,02,03,08,09,0F,11,15,16,17,18,36,37,45,46,55,56 ,57,65,67,69,75,76,77

-------------------------------------------------------------------------------
Address 01: Engine Labels: Redir Fail!
Controller: 8E0 909 518 AF
Component: 1.8L R4/5VT G 0002
Coding: 0016751
Shop #: WSC 63351
VCID: 749B5FD357A3
6 Faults Found:
17544 - Fuel Trim: Bank 1 (Add): System too Lean
P1136 - 001 - Upper Limit Exceeded
17519 - Shareware Version. To Decode all DTCs
P1111 - 002 - Please Register/Activate - Intermittent
17978 - Shareware Version. To Decode all DTCs
P1570 - 008 - Please Register/Activate - Intermittent
16684 - Random/Multiple Cylinder Misfire Detected
P0300 - 001 - Upper Limit Exceeded - Intermittent
16687 - Shareware Version. To Decode all DTCs
P0303 - 001 - Please Register/Activate - Intermittent
16688 - Shareware Version. To Decode all DTCs
P0304 - 001 - Please Register/Activate - Intermittent
Readiness: 0000 1001

-------------------------------------------------------------------------------
Address 02: Auto Trans Labels: 01V-927-156.LBL
Controller: 8E0 927 156 P
Component: AG5 01V 1.8l5VT USA 0910
Coding: 0001002
Shop #: WSC 63351
VCID: 3B09B4EF3A7D
No fault code found.

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 8E0-614-517.LBL
Controller: 8E0 614 517 H
Component: ABS/ESP allrad 2328
Coding: 04277
Shop #: WSC 06435
VCID: 2D2D8AB7F409
No fault code found.

[chrisdeaner]

FYI drove the car a lot over the weekend and no CELs yet. I didn't get a chance to run through the complete readiness prep steps but had it at freeway speeds for a good amount of time along with some extended idle times. I did notice the idle would be very, very smooth at times and then slightly higher/rougher but again no mis-fires I could detect or CELs. I did get the oil pressure warning again after about 30min of driving and coasting/off the accelerator but this was always accompanied by the CEL coming back before so not sure if it's now something else. I'll be able to drive it some more next week and will continue to post results and hopefully can get in to replace the remaining few check valves to see if that makes a difference as well.

[Furly]

FYI drove the car a lot over the weekend and no CELs yet. I didn't get a chance to run through the complete readiness prep steps but had it at freeway speeds for a good amount of time along with some extended idle times. I did notice the idle would be very, very smooth at times and then slightly higher/rougher but again no mis-fires I could detect or CELs. I did get the oil pressure warning again after about 30min of driving and coasting/off the accelerator but this was always accompanied by the CEL coming back before so not sure if it's now something else. I'll be able to drive it some more next week and will continue to post results and hopefully can get in to replace the remaining few check valves to see if that makes a difference as well.

Oil pressure is sometimes the oil pump's pickup tube screen getting clogged. A good idea would be to drop the oil pan and inspect it. Its pretty easily accessible and if its clogged you can either clean it or buy a replacement. Theyre pretty cheap.

[chrisdeaner]

Oil pressure is sometimes the oil pump's pickup tube screen getting clogged. A good idea would be to drop the oil pan and inspect it. Its pretty easily accessible and if its clogged you can either clean it or buy a replacement. Theyre pretty cheap.

Thanks! Do you know if there is a write up discussing this?

Also just FYI the oil pressure warning went away once I had the suction pump replaced last year and only came back again once the CEL came back which made me think they could be related. So far I haven't seen another CEL after replacing the check valves I mentioned above but also not 100% sure I've driven it enough (won't be putting more miles on it until next week).

[chrisdeaner]

FYI, cross post from the main strengthening thread:

Pulled the codes, somewhat the same so going to go ahead with more check valve swap and see where that gets me.

VCDS-Lite Version: Release 1.2
Saturday, 20 August 2016, 09:14:27.


Chassis Type: 8E - Audi A4 B6
Scan: 01,02,03,08,09,0F,11,15,16,17,18,36,37,45,46,55,56 ,57,65,67,69,75,76,77

-------------------------------------------------------------------------------
Address 01: Engine Labels: Redir Fail!
Controller: 8E0 909 518 AF
Component: 1.8L R4/5VT G 0002
Coding: 0016751
Shop #: WSC 63351
VCID: 749B5FD357A3
5 Faults Found:
17978 - Engine Start Blocked by Immobilizer
P1570 - 008 - Implausible Signal - Intermittent
16684 - Shareware Version. To Decode all DTCs
P0300 - 008 - Please Register/Activate - Intermittent
16685 - Shareware Version. To Decode all DTCs
P0301 - 008 - Please Register/Activate - Intermittent
17519 - Oxygen (Lambda) Sensor Regulation: Bank 1: System too Lean
P1111 - 002 - Lower Limit Exceeded
17544 - Shareware Version. To Decode all DTCs
P1136 - 001 - Please Register/Activate
Readiness: 0000 0000

-------------------------------------------------------------------------------

[chrisdeaner]

Cross post from the main thread:

OK so fab'd up a hose with 1/4" heater hose to connect the first check valve, similar to what jonan did. Prob could've gone with 5/8" as it was a tight fit but this isn't going anywhere.



Also replaced the #3 check valve in this thread with a US plastics. I had seen in earlier posts in this thread that #s 2&4 in that thread I linked to could also be replaced with US plastics but now I'm not 100%. Are these their own part # to be replaced with OEM or can they be US plastics? Anyway, took it for a spin after all this and it seemed to be much more responsive and much quieter/smoother at idle. I don't have a way to get the boost psi (unless I can pull that with VCDS-lite?) so can't say for sure but seems to be better. We'll see if the CEL/oil pressure light comes back.

Lastly, while poking around after the 2 installs I noticed the end of this pipe that appears to be threaded but has nothing attached to it... Any ideas? This is directly to the top right of the valve cover cover (whatever the plastic thing is called with the Audi logo on hit held on by the three plastic "screws" of which I've lost 1) and right near the suction pump...

[chrisdeaner]

Another cross post...not sure what the issue is now:

Ugh, CEL and oil pressure warning back again:

Address 01: Engine Labels: Redir Fail!
Controller: 8E0 909 518 AF
Component: 1.8L R4/5VT G 0002
Coding: 0016751
Shop #: WSC 63351
VCID: 749B5FD357A3
3 Faults Found:
17978 - Engine Start Blocked by Immobilizer
P1570 - 008 - Implausible Signal - Intermittent
17519 - Shareware Version. To Decode all DTCs
P1111 - 002 - Please Register/Activate
17544 - Shareware Version. To Decode all DTCs
P1136 - 001 - Please Register/Activate
Readiness: 0000 1001

Will keep digging.