Got a coolant fault warning P1B1C00 water pump mechanical malfunction.

[Fast4esT]

2014 Q5 3.0T stage 2/merc HX

I’ve got this awful putted sick feeling in my stomach and expecting the worst and hoping for the best.
Started a road trip from northern Michigan to the outer banks NC Thursday evening, spent a night in southern Michigan Thursday evening. Drove to DC Friday afternoon, everything has been fine mostly.
Thursday I felt 1 really light I wanna say misfire or stumble, just barely felt it in car and gas pedal whiles cruising 75 ish light foot on pedal. Friday it happened again 2 more times just once each but was much more abrupt and felt, like brief fuel cut feeling? Scares ya a bit then all was fine and has not done it again the rest of 4 hours on the road.
About 1.5 hour northwest of DC I got this dash warning :
“Cooling system fault, turn off engine”
No CEL, gauge was at mid normal mark

Watched the gauge and drove to next exit.
Turned car off, checked the coolant, it’s full, no smells, no excessive heat felt from engine bay, felt normal.
Scanned with OBDeleven, got a “P1B1C00 coolant pump mechanical
Malfunction”
Clicked for more Google info and seen a fair amount of info with this coming up for no apparent reasons. People have mention replacing water pumps, t-stats, sensors, reservoirs only to have the warning randomly come back. Some have said they just reset it and keep going for months long as it is not overheating.
There is a tsb also for ecu software update and this false code

But I’m not just assuming I have nothing more than a software glitch.

With no lost coolant or overheat situation we left the reader plugged in and drove the 1.5 hour to DC. Coolant sensor 1 read between 95-99°C the whole time, sensor 2 read 113-117°C whole time. Gauge Needle never rose above normal mid mark. We were doing 65-70 rest of the year at light foot on the pedal. Had no known issues or trouble other than fear of the unknown.

Is it normal for the two temp sensors to read differently? Like engine temp is normally higher than coolant temp?

I left the car at a mechanic in Rockville MD at a shop my friend recommended and takes his sprinter van to. It’s not an Audi specialist but sounds like a safe place??
I will talk with them again Monday., they should be able to look at it Tuesday. I left a note of what happened.

I cleared the codes when we stopped, I have had no new codes come up.

I recently installed 187 crank pulley and 034 stage 2 and merc HX. I’m expecting maybe not 100% of air got bled from system but with heat on hi and fans low I get great heat so figured it was good. Did too it off one time after 100 ish miles which seems normal if some air moved.
Not sure if that could have triggered this? But 500 miles later? Prolly not

Tech friend back home says don’t worry too much if not overheating but suggested the pump could be stuck open and to have it vacuum checked for operation?
Just need some words, gonna be a long weekend.
I can answer any questions if I’ve missed something.
Not expecting internet problem solving here;)
Continuing on the road in another car, hoping I can come back to pick mine up next week and take it down there.
Thanks for listening, I’m sure some of you have had this experience before.

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Here is the TSB

https://www.audiworld.com/forums/a6-...ngine-2939491/

[SwankPeRFection]

Your link is messed up. Here’s the right one for the TSB.

https://static.nhtsa.gov/odi/tsbs/2016/SB-10091807-0699.pdf

[SwankPeRFection]

Also, since you recently flashed this car, there’s a good chance 034 didn’t use the correct base software flash version that fixes this issue. For your model year, it’s just the software revision and not a physical part number problem. You need to scan the car and get the ECU box code and revision number and compare that to what the TSB says it needs to be on to have the issue fixed. If it doesn’t match up, you need to call 034 and tell them there’s an issue. If you didn’t have this problem before their flash, chances are good you were already on the latest release, but it’s very strange for them not to poll the ECU first and get their flash to match those revisions prior to just writing the new flash. This isn’t normal practice on this platform.

I don’t think your mechanic friend if a friend is going to be able to do anything about this and hopefully he’s not going to tear into the water pumps needlessly if this relates to what I stated based on the TSB info.

[Fast4esT]

https://cimg3.ibsrv.net/gimg/www.audiworld.com-vbulletin/1284x2000/80-3e3be88f_60d8_42fa_a0ba_386df8a965ef_d3a76f475c28c 7cedc2ecc3543df161167c40dcb.png

These are the two temp sensors I saw
Sensor 1 highest I saw was 99C
Sensor 2 highway I saw was 117C

This photo is from today on the 10 minute drive to drop car off.
Temps seemed normal again today, sat idle for a few minutes also to watch them and saw peak of 96C on sensor 1, and 109 on sensor 2. They fluctuate up and down driving by 2-4 degrees each with coasting and accelerating. Nothing major

[Fast4esT]

Have not had this issue before, have owned car 13 months and 10,000 miles. Went stage 1 034 a couple months ago, just went stage 2 034 in the last week

Mechanic, I do not him or the shop. It’s 800 miles from home:(

Buddy back home is a tech but not much help this far away.

I will talk with the shop before they look at the car and before they do any work beyond diagnosis.

So you think it’s possible that this is software related and not a real threat to the engine? That’s a relief but still yikes.

I’m not aware of the ecu i go but will try to get it when I talk with the mechanic. I’m a couple hours away from it now.

So, if my ecu software was latest release and 034 is not, it will revert to the older version? Seems like this should have come up before if it was an issue with 034 tune?

I’m not jumping any conclusions yet, thank you for helping my understanding.

I did read on an older post that the only way the water pump can fail is by leaking, it is just mechanical. I was under impression there is a diaphragm in the pump that could have a small tear or be stuck open or closed and can be checked by adding vacuum to the pump and see if you can hear the diaphragm close?

Current mileage is about 71,000

[SwankPeRFection]

I’m not saying anything in terms of what it could be because the software you’re using is somewhat useless in terms of granular diag info. That said, you need to pull the ECU box codes (via software/maybe whatever software you’re using can or can’t do this) and compare it. Based on the exact code you got, you need at least that base info in regards to that TSB. The engine water pump usually doesn’t set a code when it fails, especially not a mechanical fault code. That’s usually something the intercooler pump will trigger as it is electric and hooks up and the ECU can sense if it’s running. I guess Audi could set a code if there’s a lot of deviation between temp readings on the main water pump loop for the engine, but that’s also indicated by your water temp gauge on your dash going up beyond half and overheating and also your fans running full blast after you turn the engine off. On this platform those are usually the telltale signs of a failing thermostats or water pump or anything else where the engine is overheating.

Because there’s so many revisions for the Q5 ECU box codes, it’s possible that 034 based their tune on a version that with your particular hardware revisions could be triggering a false positive error per that TSB. Since you just recently flashed their tune, it’s possible this could be it, but it’s also possible it could be a legitimate failure of the coolant pipe. Like I said, without some specifics which you don’t have right now because you don’t have your car, can’t give a clear answer.

[Fast4esT]

No CEL, only thing engine related I pulled was the P1B1C00 water pump mechanical malfunction. I assume that is just generic. There was no fault codes elsewise

I’ll see if I can get ahold of the ecu info

[Fast4esT]

Fans did not kick in when turning car off, didn’t notice them get louder while driving either. When I stopped engine never felt hotter than normal. We did have the AC running on low on the way down so some fans must have been on?
HVAC I had turned off today when I was driving to drop it off at the shop.

Can I ask about the 2 different sensors with different temps? Is that normal ?

Sorry for all the posts, just trying give all info I have. It’s hard and nerve wrecking being now so far from the car
Your responses are much appreciated !
Saving me from having major panic attack

[SwankPeRFection]

Not sure about the 2 sensors because to my knowledge there’s only one for the coolant and it’s in the plastic water pipe on the front of the engine. It’s possible the newer revisions of the 3.0T in your might be different but this would be a new one on me. Like I said, I’m not familiar with whatever software you’re using to pull that info. Most of us here will use VCDS to pull codes and diagnose stuff on Audi/VW cars.

[Fast4esT]

I’m using OBDeleven. Only finding the 2 pin temp sensor on all store sites.

[SwankPeRFection]

Does OBD11 even show you ECU flash version and revision code? That’s the first thing you need to pull to see what it’s on. Right now you’re chasing ghosts. Compare that info against the TSB and see where you are. If you’re on the correct revision which fixes the software based false-positive of this error, then you can look at the mechanical side of things for a failure.

[SwankPeRFection]

Apparently it’s under ECU and Info. Take a screenshot of that and post it.

[Fast4esT]

Thanks, I will when I get back to it and post back later in the week.
Thanks for the help!

[Fast4esT]

Have not got back to car yet or heard from the shop either but I did get an email back from 034 with my ecu box code and revision which they said is the same as was before, 8R0907551F 0007, checks out as current revision according to the service bulletin.

[Fast4esT]

Original shop didn’t want to mess with or know what to say about the car as it wasn’t overheating nor have any codes. I don’t th k they had vcds either. Found an Audi specialist shop that I’m finding I really like so far, S2 Dynamics in Rockville MD. Very knowledgeable in our motors and modding them, they are replacing the thermostat expecting it to be stuck open.
Reminds me back to this winter it could take up to 15 minutes for the gauge to get to normal mark, sometimes when it was almost there it would drop back to 1/4 and slowly rise up again. I had been questioning the tstat for a bit but wasn’t sure if that was normal? Our winter in MI was by no means a normally cold wi get either but still needed to use the heat.
Last time I checked heat at idle 1.5 weeks ago it was really good and hot

[SwankPeRFection]

In winter it can take a bit to come up to normal temp. Thermostats almost always fail in closed position on these engine. Just FYI.

[Fast4esT]

Ha great! What makes them normally fail in closed position?
The thing that made me wonder about it is that sometimes when it would get 3/4 to of the way to normal mid mark it would drop back to 1/4ish and slowly rise back up. I read one post that was happening with someone else in the past and told its normal if the beats running but I haven’t noticed it ever in previous Audis or other cars

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If the warning comes back I’m gonna get the N489 solenoid but gonna confirm with shop if I can that it is working properly