Fans staying on long after engine stops ...

4.2 V8 40v biturbo - 450 bhp
4.2 V8 40v biturbo - 480 bhp (plus)
User avatar
GardinerG
Top Gear
Posts: 2285
Joined: Mon Apr 30, 2007 9:58 pm
Location: Fleet, Hampshire

Post by GardinerG » Fri Jan 04, 2008 12:37 pm

My G2/62 is on it's way out (due to be replaced in a week when I can get it booked in) but it only throws an intermittent error code and no MIL, plus the temp gauge "seems" fine. FWIW.

G

User avatar
HyOctane
Neutral
Posts: 44
Joined: Fri Jun 15, 2007 10:45 pm
Location: Los Angeles, CA

Post by HyOctane » Fri Jan 04, 2008 7:52 pm

Mine is exibiting this as well. except that it comes on at water temp 170 F and stays on after engine is switched off.. All gauges are normal.. no MIL but the techs said the bearings were failing in the 600w fan so they have orderd a new one from der fatherland and a new control module is attached to it. should solve problem.

skiwi
4th Gear
Posts: 557
Joined: Sat Jan 13, 2007 10:58 am

Post by skiwi » Sat Jan 05, 2008 12:01 am

there are 2 separate monitoring functions: one for the cooling system, and the other for the engine coolant sensor.

the temp sensor will throw codes (range: p0116, low: p0117, high: p0118) when "rationality" of readings is in doubt. these codes are only thrown after a number of on/off engine cycles. the decision is made after consideration of the difference between successive high and low values (above the thermo control temp). only when this is true does a mil get thrown.

the cooling system has the p3081 code (cooling temp too low), and p2081 "cooling system performance" for when the engine doesn't warm up fast enough (based on calculated air mass flow).

interestingly, there is no code thrown for *cooling system* over temp, only one for the *temp sensor* "out of range" or "stuck".

considering the above, it appears that the main focus on for bosch in me7 is efficient warming up - therefore on emissions, not on whether the cooling system is protecting the engine.

User avatar
HyOctane
Neutral
Posts: 44
Joined: Fri Jun 15, 2007 10:45 pm
Location: Los Angeles, CA

Post by HyOctane » Sun Jan 06, 2008 1:39 am

Its funny how a loose gas cap will trigger a CEL, but a failing cooling fan wont.

skiwi
4th Gear
Posts: 557
Joined: Sat Jan 13, 2007 10:58 am

Post by skiwi » Sun Jan 06, 2008 4:58 am

everyone is paranoid about emissions. what is the bet that there are penalties for the manufacturers if they didn't do this?

User avatar
HyOctane
Neutral
Posts: 44
Joined: Fri Jun 15, 2007 10:45 pm
Location: Los Angeles, CA

Post by HyOctane » Fri Jan 11, 2008 8:00 pm

Ok. Well, the new fan and control module didnt change anything. Fans still running constantly as described above. Next?

pxl108
Neutral
Posts: 24
Joined: Fri Nov 24, 2006 9:11 am
Location: Wakefield

Post by pxl108 » Sat Jan 12, 2008 4:21 pm

After a couple of weeks of fans running at full speed, the true cause became apparent on Thursday - i was rescused by the AA and traveled home on the back of a flat bed truck - 10 out of 10 for those who said Thermostat - the car finally started to show signs of overheating on the M1, so i pulled over and sobbed onto the steering wheel !. Audi quoted £18 for the Thermostat, and £1000 to fit it - Spoke to the warranty company on friday and spoke to the same guy who was looking after my DRC failure - another couple of grand claim !! - i could actually hear him groan when i broke the news to him, but they are covering the cost of it so i can breath a huge sigh of relief .........

After all the trouble i have had with it (Over 3k of bills in the first 3 months !!) i am now considering selling it ..........

Rek
2nd Gear
Posts: 155
Joined: Tue Feb 13, 2007 8:58 pm
Location: London
Contact:

Post by Rek » Sat Jan 12, 2008 4:43 pm

I had both these troubles, and there is an easy solution to save you money. PM me for guidance.

pxl108
Neutral
Posts: 24
Joined: Fri Nov 24, 2006 9:11 am
Location: Wakefield

Post by pxl108 » Sat Jan 12, 2008 4:52 pm

Hi Rek - luckily i spoke to Grizz, and the warranty company have authorised him to do all of the work, DRC replacement and thermostat .....so i should be on the road again by wednesday ....... PM also sent for more advice :-)

Rek
2nd Gear
Posts: 155
Joined: Tue Feb 13, 2007 8:58 pm
Location: London
Contact:

Post by Rek » Sat Jan 12, 2008 6:05 pm

Thats the guidance. You are in the right hands. I'll reply to PM.

skiwi
4th Gear
Posts: 557
Joined: Sat Jan 13, 2007 10:58 am

Post by skiwi » Sun Jan 13, 2008 7:27 pm

that leaves the g2/62 or the thermostat. they have very similar failure symptoms. i spent 2 weeks chasing and fixing a g2/62 only to find the thermostat had gone as well (on my old s8). remember that the g2 is the ecu sender, while the g62 (in the same body) is the dash/climate sender. hence it is possible to get a correct dash reading while the ecu doesn't. use vagcom to get the real ecu reading.

User avatar
HyOctane
Neutral
Posts: 44
Joined: Fri Jun 15, 2007 10:45 pm
Location: Los Angeles, CA

Post by HyOctane » Sun Jan 13, 2008 8:08 pm

Thx Skiwi.. It'll be going back tomorrow. I'll tell them.

User avatar
Rupert
5th Gear
Posts: 1138
Joined: Thu Jun 23, 2005 12:57 pm

Post by Rupert » Mon Jan 14, 2008 9:42 am

So is it best to get the thermostat repaced when the cambelt is done?

User avatar
GardinerG
Top Gear
Posts: 2285
Joined: Mon Apr 30, 2007 9:58 pm
Location: Fleet, Hampshire

Post by GardinerG » Mon Jan 14, 2008 1:02 pm

Rupert wrote:So is it best to get the thermostat repaced when the cambelt is done?
Yep!

User avatar
alangjones
2nd Gear
Posts: 214
Joined: Thu Apr 27, 2006 3:12 pm

Fan staying on

Post by alangjones » Sat Jan 19, 2008 6:43 pm

See my post on water temp and the water pump
rs999 on Blues and 2's

Post Reply

Return to “RS6 / RS6 plus (C5 Typ 4B) 2002-2004”

Who is online

Users browsing this forum: Google [Bot], srichards and 66 guests