3B engine overheating problem?

[Jarno]

Hello.

I have problem with my 3B engine.

When car is running on the same place it's try to overheat engine.

Engine temeparature goes over 100 degree.

-Engine have little modification like bigger turbo.
-Engine is running with VEMS.
-Head is pressure tested and result was no leaking. Head have one crack but it not leaking.
-Thermostat is changed low temperature version and it have been installed correct position.
-Water pump is almoust new. Only 5000km old.
-Radiator is changed 5 years ago.
-After run switch is changed low temperature version.
-Fan is working normally.
-Radiator is in the original place.


This temperature is checked couple of ways. Original gauge, VEMS and seperate temperature gauge. I but this sensor straight to the water pipe what gomes out of head and goes to radiator.

Does somebody have same kind of proplem?

Have anybody changed fan to better version? And how about the result of this change?

Maybe this water pump is broken? I need to remove that and check it but it takes lot of working hours.

If somebody have solved this kind of problem please tell.

[Pirvu Eugen]

Termoswitch defective, wiring, relay....
Remove the plug from termoswitch and jump the pins to check the correct fuction of the wiring..
Iff this checks ok..... Termoswitch, radiator blocked, termostat, water pump, air lock...

[mike74]

Check everywhere for any leaks. Could just be an air lock though as they're not good to bleed. Has this just started suddenly or has some components been disturbed that might cause this?

[220bhp]

Did you check the head for corrosion when you had it of. Waterways corrode if the wrong antifreeze has been used during the cars life.

[Jarno]

This problem come after engine rebuilt. There was no corrosion in water canals.

There are no leaks. There are no air in the system. Air is removed many times.

When fan is running temperature is going low. But if outside temperature is +25 fan is running almoust continous and engine temperature is rising slowly to over 100.

This car doesn't have air condition.

[domas]

It might be a long shot, but it might be your VEMS tune running too lean (read:knocking) or too rich.
But I fail to see some info in your post. Does the fan (slow speed) kick in when it is supposed to? Stock is 93C, not sure about your setup. Same with fast speed, 105C in stock setup iirc, does it kick in when it is supposed to? If yes, that rules out fan electronics

[Jarno]

Fan is running speed 1 if temperature is rising.

When car is running idle, sometimes it sound like one spark is missing. And if i take flue gas test. Test result is not good. Engine HC is too high.

Some times when car is running idle lambda can be 0.93 and sometimes it can be 1.1.

It doesn't matter if you but lambda to 1.0 then after couple of driving hours it goes 0.93-1.1.

I don't know how this is possible.

[quattro-nick]

is this the first time you install vems on the car after the engine rebuild?
maybe you need to check your ignitiontable because with late timing the temp will also increase

[220bhp]

When the car over heats does it push coolant out of the header tank. Or are the hoses hard.

[domas]

Fan is running speed 1 if temperature is rising.

When car is running idle, sometimes it sound like one spark is missing. And if i take flue gas test. Test result is not good. Engine HC is too high.

Some times when car is running idle lambda can be 0.93 and sometimes it can be 1.1.

It doesn't matter if you but lambda to 1.0 then after couple of driving hours it goes 0.93-1.1.

I don't know how this is possible.

Make your car run perfectly to start with. This may be the problem.

[Jarno]

Hi. I will take today my car in road use so I can take log-file. I take log-file when it's running idle in warm engine. Maybe I can send config-file too.

Kenax have done these car VEMS setting. He set idle running perfect but it make what I told earlier.

I'm thinking is possible that cam timing is not correct? When I set this timing I was checked it many times. Cams have adjustable cam gears. I set these cams to original value. And cams are original.

Engine have EV14 injection size is 1100cc.

And inginition is changed to 1.8t set. It have these FSI coils.

[Colesy]

Is the fan wired the correct way around. If it's blowing the wrong way in hot temperatures it's not as effective and can lead to similar issues. Don't ask me how I know.

[domas]

at normal cruising speeds 80km/h+ fan should not be necessary at all. And I don't think that temperature over 95C+ is normal for cruising in the city as well. My fan kicks in @ 92-93C and cools down the engine to 87-ish, in like 1 minute.

My knowledge is based on 2 radiator having 200 20v, but IIRC s2 has two rads as well?

[andy10v]

Have you checked the radiator is not blocked?

[Jarno]

Hi. Fan is connected original connection. So it shut be working right way.

When I driving like 80-100km/h temperature is 87-92C. When I stop and engine is running temperature start to rise slowly and goes almoust 105C.

I don't have checked radiator radiator because before engine rebuilt it working correctly. And before engine rebuilt I have motronic. Now I use VEMS.

This second radiator is removed car about 10 years ago.

I will send this log- and config-file later. If I know how to add these files here.