The definitive VR6 cooling guide

[aide 0]

They're a sealed unit, you need to unscrew the fuse on the top of the unit and remove, then carefully cut away the rubber seal round the base, you'll then have to lever the tabs on all four sides then pull the innards out.

 

With a bit of luck you may be able to see a loose connection, otherwise you'll need to be a dab hand at electronics to diagnose.... all assuming that's where the problem is of course!

[jpowell79 0]

well I put my new thermostat housing and seals on the car, and thought I'd try out the fans after clearing the fault codes (ABS ones) with VAGCOM........and now none of the fans come on!!

 

At least before stage 3 was working...now nothing!

 

Back to the drawing board :scratch:

[jpowell79 0]

 

Fans/pump after-run fault-checking

You can use the following procedure to find out if your yellow temp sender is the cause of no after-run or not. This does not necessarily prove that the yellow temp sender is working, but it will prove if the circuitry that it controls is working or not.

 

Turn ignition key on, then off again

 

Disconnect the 4-pin connector from the yellow temperature sender switch

 

Bridge contacts B, D (brown/red and brown wire)

 

The radiator fan and auxiliary coolant pump must come on

 

If NO, check the fan control unit and/or the aux water pump.

 

 

Dinkus could you please verify.....when you say turn the ignition on, do you mean turnit so the lights come on (or do you mean actually start the engine?)

 

From the post I read it to mean that you start the engine, then turn off the engine but so that the lights are still on?

 

After all, how would anything happen if you switched the lights on, then switched them off completely (as thought the key was not in the ignition) and then expect the fan to come on after bridging B and D on the cable?

 

Sorry, just need some clarification....after all, I've tried bridging the black cable that controls the stage 3 fan before and nothing happened (even though my stage 3 was working at the time!)

 

cheers.

[joeyboswell 0]

I am a bit confused with my cooling system and I haven't ran the checks listed in this thread yet. I think my temp readings may be lying to me. I can drive with low revs and take it easy...and the stage 3 fan will come on with the water about 80-90 and oil 90-104. Popping the bonnet and the engine is really quite hot but I haven't had a VR6 before so I don't know if this is the normal high temps they run at.

 

I have put my VR6 into my mates garage today for a general check-up to see if anything is on its way out. His mate is coming around with his diagnostics gear. My question is will any faults with the sensors and switches show up when connected? I'm not sure what they have in the garage already and what his friend is bringing but I'm sure something will connect to the OBD1 system and they might have a proper VAG-com kit. Will any of these show up the faults with the cooling system?

 

I'm worried that I could be doing damage to the engine because I have had the tensioner pulley and belt go when I first bought it (about 2-3 weeks ago) but replaced that without driving it when it was goosed.

[Critical_Mass 10]

VRs do run hot, but the water should sit at 90 and the oil at 90-104 as you say, that is a normal temp.

 

Plugging vagcom (assuming he's using vagcom) in will be able to read the water temperature from the ECU which gets its reading from the blue temp sender on the front of the engine. The dash temp gauge reads from the yellow (new ones are black). So you can check them against each other to see if the dash gauge is reading correctly or not. Or if the reading in vagcom is way higher then it could be the blue temp sensor needs replacing. The yellow and blue sensors are cheapy cheap btw.

 

But going by what you've stated as the temps they seem fine. If anything it sounds like theres an issue with the fans.

[joeyboswell 0]

Yeah my water is normally about 80-90 and 90-104 but that has been with easy driving. I hope they check the temperatures. If not I will have to go to VW who will probably rape my wallet! I'm thinking I may just chage the sensors anyway for piece of mind. Will any problems with the fans be picked up by VAGcom or other diagnostics?

 

I'm being so paranoid it's unbelievable! I'm even starting to think that the car shakes too much when idle. Should you get a little bit of a feeling in the seat when idle? Not like shaking but little pulses. My car sits at the same really low revs when idle (don't even think it reads at anything on the dash!).

 

Cheers Critical_Mass!

[Critical_Mass 10]

Yeah my water is normally about 80-90 and 90-104 but that has been with easy driving. I hope they check the temperatures. If not I will have to go to VW who will probably rape my wallet! I'm thinking I may just chage the sensors anyway for piece of mind. Will any problems with the fans be picked up by VAGcom or other diagnostics?

 

I'm being so paranoid it's unbelievable! I'm even starting to think that the car shakes too much when idle. Should you get a little bit of a feeling in the seat when idle? Not like shaking but little pulses. My car sits at the same really low revs when idle (don't even think it reads at anything on the dash!).

 

Cheers Critical_Mass!

 

Your mechanic should be able to check the fans. If you have a look under the fans in Dinkus' post it tells you when the fans should come on i think. If its doing anythigng different it could indicate a problem.

 

As for the idle, yeah a few pulses as such you can feel through the seat. The revs on my VR sit around 500-600 rpm on idle but it does feel like it pulses every so often but the rev counter doesnt move. (ah just noticed you put the same above) yeah thats fine! :D

 

One thing you could do if you've just bought it is, if you take all the engine plastics off at the top of the engine, next to the throttle body, you will see a metal cylindrical shaped piece that has a plug going into it and is held on by a piece of plastic wrapped round it - this is the Idle Stabiliser Valve (ISV), take it off and give it a clean with some carb cleaner. Even hold open the valve with a flat head screwdriver and spray in there. Just to get any muck out that could case lumpy idle.

[cmlamont 0]

I have a problem.

 

My cars guage is reading low. It doesnt get above 70 or 80. But fan comes on. Therefore guess that this is a problem related to the yellow sensor.

 

My car after warming up starts to overfuel and flood the engine - it then would appear to go into safe mode, as i cant rev above 5000rpm. I have decided that if I'm changing the yellow sensor I would change the blue one which sends signals to the ECU - just in case the car thinks its running in cold start mode all the time.

 

Get the parts from euro car parts. The yellow one is black - OK from the forums, but when installed and I attach the lead, the fan kicks in immediately. This would appear to me to be a problem with the sensor, however by mistake I was sent 2 of the same sensor so tried the other one in the socket without installing into car and same thing. Now surely only when the car heats up should the sensor switch the fan on.

 

My sensor part number is 701 919 369 B - not 701 919 369 D which is stated on all other forums.

 

The blue part that arrived today is the wrong part so I'll be sending that back.

 

Any ideas on whats going on with the sensor? Am I doing the right thing in regards to changing these anyway?

[joeyboswell 0]

Just got my VR back from a VW specialist after about 6 weeks of ownership. Took it in to get the fans, temps etc looked at and also a whiny noise when turning without moving....as well as a general look at to see if anything needed doing. Turned out there was loads to do (wishbones, rear shocks etc) so just got it all done. However nothing was done about thesteering noise (they couldn't hear it) and the fans, temp sensors etc. The only thing done that is related to the oil temps is that I had the oil cooler seals replaced. Since I have got the car back it is reading much higher temps. Drove to London and back yesterday and the oil temp didn't go below 100 and got as high as 116 (generally it was 112-114)...but I was booting it! Does this sound like I should be worried? Is there any explanation why the temps are suddenly higher when nothing has been done other than the oil seals? Is it now giving a truer reading? I also got a stainless cat-back exhaust but can't see that doing anything.

 

What would you suggest should be my first thing to look at? And then the second, third and so on!?

 

Cheers

[craigowl 0]

I dont have oil cooler in (standard) VR6. My oil temps are 80-100C normally. Dont thrash it, but have been in heavy traffic in hot weather, etc.

From previous discussions your temp. sounds high, but not excessively so.

Why the oil cooler anyway? :confused4:

[Jon_vr6 1]

I dont have oil cooler in (standard) VR6. My oil temps are 80-100C normally. Dont thrash it, but have been in heavy traffic in hot weather, etc.

From previous discussions your temp. sounds high, but not excessively so.

Why the oil cooler anyway? :confused4:

 

Vr6's come with an oil cooler standard mate its just a very small one on the front of block

 

Temps seem high mate whats it like when your not thrashing it though ??

[craigowl 0]

I dont have oil cooler in (standard) VR6. My oil temps are 80-100C normally. Dont thrash it, but have been in heavy traffic in hot weather, etc.

From previous discussions your temp. sounds high, but not excessively so.

Why the oil cooler anyway? :confused4:

 

Vr6's come with an oil cooler standard mate its just a very small one on the front of block

 

Temps seem high mate whats it like when your not thrashing it though ??

 

Ooops, sorry! - my ignorance on that point. Jon.

I was thinking of one of those add ons that some have and have discussed on here. Probably need bigger oil cooler with supercharged, etc versions?

[joeyboswell 0]

I dont have oil cooler in (standard) VR6. My oil temps are 80-100C normally. Dont thrash it, but have been in heavy traffic in hot weather, etc.

From previous discussions your temp. sounds high, but not excessively so.

Why the oil cooler anyway? :confused4:

 

Vr6's come with an oil cooler standard mate its just a very small one on the front of block

 

Temps seem high mate whats it like when your not thrashing it though ??

 

well before it went in the garage I was getting 90-104 (up to 104 when giving it some beans!). Literally straight after picking it up I was getting higher temps like 98-102 with normal driving and about 112-114 (occassional 116) at high motorway speeds. Normal driving is nothing too bad...high but not excessive (from what I have read on here). Just rang the garage and they said that nothing they have done should have caused me to get higher oil temps and that I need a new thermostat (and therefore housing!). I don't want to just replace that and then it not be solved. I just searched and G-lad done all of this to get the right temps:

 

"check the heat of the radiator in all 4 corners after the drive (ie once the thermostat has opened). i replaced my thermostat and houseing twice, and all the sensors (3 in housing, 1 in rad) AND the fan control box AND the coolant-to-oil heat exchanger AND the electric water pump AND the main water pump before the car would run at the right temp"

 

I don't have a problem with the water temps but the oil is a worry. Will the thermostat affect the oil temp much do you think?

[dukest 0]

Is there any explanation why the temps are suddenly higher when nothing has been done other than the oil seals? Is it now giving a truer reading? I also got a stainless cat-back exhaust but can't see that doing anything.

 

What would you suggest should be my first thing to look at? And then the second, third and so on!?

 

Cheers

 

not sure what to suggest apart from the fact that those temps are highish but not a disaster.

 

before i put the extra oil cooler on i began getting the same as you - it would sit around 112 at 100mph and rise accordingly - and that was after changing the waterpump, thermostat and radiator. compared with yours before and with craigowl the new temps are obviously higher but as long as you change the oil regularly 110ish isn't a big issue though. i sympathise that its annoying though :(

[joeyboswell 0]

it is annoying! bloody annoying! I'm pretty laid back but thought I would try to look after my new car, stay on top of things and hopefully save myself money by stopping things going drastically wrong! This thing though doesn't seem that simple. Would changing the a different oil help the temps at all? It's still got what the previous owner was running as it had a service before I bought it. Would a thicker, synth oil work reduce temps in any way or just be able to cope with them better? Suppose I best get a oil, coolant and general fluids change and see what happens. cheers for the help anyway lads.

[Critical_Mass 10]

If there oil temps they look fine to me. If you were booting it and the weather was warmer?

[chazrad 0]

it is annoying! bloody annoying! I'm pretty laid back but thought I would try to look after my new car, stay on top of things and hopefully save myself money by stopping things going drastically wrong! This thing though doesn't seem that simple. Would changing the a different oil help the temps at all? It's still got what the previous owner was running as it had a service before I bought it. Would a thicker, synth oil work reduce temps in any way or just be able to cope with them better? Suppose I best get a oil, coolant and general fluids change and see what happens. cheers for the help anyway lads.

 

Hi mate.

 

First things first: welcome to Corrado ownership. :clap:

 

Second: I haven't read all your posts on this thread but It seems like you are getting yourself into a right state! So just relax and stop beating yourself up, matey. When I got my (totally standard) VR Corrado back in 2001, I recall temps in normal motorway driving conditions being about 104-110 deg. I recall seeing up to 114-116 on hot days. Now, I do not know much about the technical aspects of oil, but you are not doing any real damage to the oil at those temps. Oil starts to break down - depending on the oil, of course - above about 130 deg. Like John (dukest) says, the most important thing to protect the engine is regular oil changes, so consider an oil and filter change (for peace of mind as much as anything) if you are unsure when the it was last done. So, I'd say do not worry about your oil temps. They are not unheard of. It seems every VR6 engine is slightly different and what is normal on one is high on another, and vice versa. Don't take my word for it: Call Vince at Stealth Racing or Tim at the Phirm and ask about what normal temps on a VR are. I think you'll be reassured. :wink:

 

On oil choice, I would suggest using only semi-synthetic oil in the VR, like VW Quantum Synta Silver oil sold by the dealers. I use it now - recommended by The Phirm - in my VR6 turbo, which potentially sees much higher engine temps than you will see. My view now (and everyone has an opinion on this, I know :lol: ) is that if VW recommend it, it must be right. Occasionally, there have been cheap deals on containers of Synta Silver on here.

 

Re after market oil coolers, you will not seem much change from £200-250 fitted from a specialist. It will drop your oil temps a few degs although the actual amount differs between cars. But, I really don't think that at this stage, with your temps, you are in need of one. If you start modifying the engine (eg. cams, remap, air filter) and putting more strain on the engine, then you might consider it. Right now, I'd give your car an oil change, let it settle down, and then if you are still worried, call a reputable specialist - as mentioned above.

 

I hope this helps. Best of luck. Charlie

[joeyboswell 0]

Nice one for the slap in the face...will get a grip of myself now! It's just that it is higher since it went in the garage which confuses me. Just edited a post were I said I was getting up to 106...it was actually meant to read 116 since it was in the garage!

 

I will give it an oil change and chill until I can get the thermostat etc sorted. I wasn't thinking of getting an upgraded oil cooler or anything like that. I'm happy to keep it standard but working as VW intended. I will hopefully leave this thread alone now...and hopefully oil temp won't go up any more! nice one lads!

[craigowl 0]

Maybe others can confirm, but if engine/oil is seriously overheating, you would smell it if you have been around cars for a while. No?

Perhaps you/someone could check temperature of engine and oil with one of those infra red sensors? Original in car could be innacurate - possibly experts can comment on these views?

kev's oil probably gets warmer than lukewarm. e.g.

 

(Sorry that should have read.....gets hot enough to incinerate a chip butty to ash in a millisecond.) :shrug:

[fla 9]

if you are getting a real 116C when you open teh bonnet you'll feel a real blast of hot air. If you can, get it on VAGCOM as you're driving or once its reached a high temp and see what shows up. May just be a calibration error. What are your water temps? Again as others have mentioned, change teh oil & filter, perhaps give teh collant system a good flush, and refill with G12++ with demin water (about 50p/litre from tesco). If the cooling system is not dumping enough heat the oil temp will build up though. Does it cool down quickly when you drop speed to say 70mph and hold it there for a while?

[joeyboswell 0]

yes I do get a blast of hot air air when I open the bonnet.

I do get a bit of a smell sometimes but I'm no expert and could be normal.

water temps are normal (80-90).

I will get the coolant system flushed and refill as you suggest...along with the engine oil (5w/40 synth).

 

I'm just pissed off that I asked the garage to check all the sensors, temps and hook it up to vagcom but I'm none the wiser if they did or not. I know he took it on test drive or 2 and looked at the temps. I was in a mad rush to get it back cos they took longer than they said so I literally just payed and left! it was already passed their shutting time and I had a big drive to London straight after. Bit weird that the temps have jumped up since I had new seals on the oil cooler. Will have to get it the vagcom on the go whilst driving.

[fla 9]

use semi synth as the engines are not really designed for the viscosity of fully synthetic oils.

[Kevin Bacon 5]

use semi synth as the engines are not really designed for the viscosity of fully synthetic oils.

 

10/40 is 10/40, whether it's fully synthetic, semi-synth, mineral or Golden syrup.

The VR6 isn't designed for any particular oil, you use a grade that suits the climate and driving conditions. I've had no trouble at all with 10W/50 and 60, even on a standard engine.

 

I don't understand all this paranoia with VR6 temperatures. If the oil is too hot, fit a mocal cooler. If it's not overheating and blowing gaskets, what's the issue?

[fla 9]

thats useful to know - i was of the understanding that the fully synthetics have the same viscosity over their temp range unlike the semis, because they're a blend of mineral and fully synth? Never mind, the key issue is if temps are too high, find the cause and remedy and ultimately fit a mocal if needed.

[Kevin Bacon 5]

Semi, fully and mineral synth multigrades are all a particular viscosity when cold (i.e.10, W = Winter) and another viscosity when hot, i.e. 40. 50 and 60 are thicker than a 40 when hot and during warm up, but the same grade when cold as a 10/40.

 

The cause of high temperatures is an almost 3 litre engine crammed into a tiny engine bay with a radiator 25% smaller than it's bigger brother's, the Golf VR6.

 

When mine was standard, it too read 114 cruising at 80, but the water temps was fine. I wasn't happy with that, so fitted a mocal, otherwise there was nothing wrong or dangerous about it, it was just personal preference.