What should my coolant temp gauge read?

[Adz_VRS]

Hi guys.

Some of you may well know that I've recently bought a lemon, a total Friday car! After having issues with coolant loss, I eventually managed to find a garage willing to take on the task ok fault finding. In the end I managed to replace the following items:

*thermostat

*coolant temp sensor

*coolant reservoir

*head gasket and head skim

*cam shells

*injector seals

*and other small associated items.

I spoke to a few tuners including darkside and they mentioned that the oil cooler in these cars are prone to degrading, so I ordered and had fitted darksides 13 row thermostatically controlled oil cooler kit too.

Now since I've had my car back, the temp gauge barely moves, I can leave it idling for 20 mins on my drive and it'll be a smidge over 50 degrees. I take it on the commute to work and again the gauge will not budge past 50 degrees. Now if I boost the car the gauge will rise but it won't stay hot at all.

Do you guys know if I should see a constant 90 degrees? I don't like this low temp as it also doesn't give much heat from my heaters. The car does have a wide mouth bumper and the garage is sure there's nothing wrong with the car. They seem to think the low temps are all down to the oil cooler but that shouldn't activate until plus 80 degrees my belief is.

I'm getting poor consumption from the car to which I assume is down to the ecu reading a low engine temp?

Ah this car has my head battered lol

Thanks in advance

[munstaar]

Stock running temps is indeed around 90 degrees mate.

[vzo25]

Is the thermostat original skoda part.

And once upto temp it should sit at 90

[KenONeill]

The reading is more or less programmed so that if the engine temperature is anywhere from about 60 to 110C, the gauge reads 90 or a smidgeon less, maybe 88.

 

So diagnostic questions:-

 

1. What sort of fuel economy are you seeing?
2. Did you get an oil thermostat? You're correct about the sort of (oil) temperature you should be seeing before the oil cooler becomes active.

[Breezy_Pete]

...I'm getting poor consumption from the car to which I assume is down to the ecu reading a low engine temp?

 

 

...What sort of fuel economy are you seeing?

 

[coskev]

When it was mentioned about about the standard oil cooler(modine) they were referring to the fact they can rust internally and let your coolant and oil mix,so did you replace this or remove it totally?

If you've removed it that will be part of your problem,the modine helps get the engine upto temp aswell as cooling the oil when it's hotter than the coolant.

Ref the air to oil cooler you've fitted,even ones with a thermostatic plate allow oil to flow through the cooler at all times.

If they were totally blocked off at the thermostat then it opened when you were at high revs it could cause a big enough drop in oil pressure to knacker your engine.

So oil is flowing through your cooler at all times,it's just the thermostat is open fully at 80degrees or whatever they quote.

I would guess your thermostat is faulty or jammed open to be seeing the issues your having with the temp rising slightly when you boot it but then dropping down again

[coskev]

[*]Did you get an oil thermostat? You're correct about the sort of (oil) temperature you should be seeing before the oil cooler becomes active.

Not totally true,see above

[KenONeill]

Not totally true,see above

Would you care to explain how the oil gets drained out of the cooler (and pipework) during cold running then?

[Adz_VRS]

Hey guys thanks for the reply. I'm on nights this week hence the late response. I paid to have all this work done so I'm going to have to investigate myself as to how the oil cooler is fitted. Unfortunately the parts were all delivered to the garage so I never saw how the configuration was before hand. I do assume that the original oil mode has been kept however it's been mentioned above that this helps warm the motor up - assuming the mo dine has some sort of sensor attached to it?

After I purchased the car I noticed that there is a sensor in the modine and a wire has been cut and put back together with insulation tape. Now I'm not savvy enough to know why or what this will do to the running of my car but I haven't had any engine lights on Ect. .. knowing my luck this wire will be impedence based and now it's been cut that has increased and maybe giving the ecu the incorrect value? I've heard of silver soldering for MAF extentions and lambda probes.

As for fuel economy, I can brim the tank with shells finest and the car struggles to see 30mpg as an average on my trip. I'm getting around 400-430 a tank and this is baring in mind I've still gotta keep my revs down as I'm running in the new cam shells. So that's not me heavy boosting or anything.

Cheers guys

[KenONeill]

Ok, a typical oil/air cooler kit should include a radiator (d'oh), 2 hoses (probably stainless steel), a thermostat, some unions (installation dependant) and a sandwich plate which goes between the block and the oil filter.

 

More generally, I'm pretty certain that either your car is over-cooled or you have a failed thermostat (don't know which) or CTS.

[coskev]

Would you care to explain how the oil gets drained out of the cooler (and pipework) during cold running then?

The thermostat never fully closes,so oil flows through the cooler all the time the engine is running,it just isn't fully open until the stated temp on kit.

[munstaar]

[quote name="Adz_VRS" post="4367067" timestamp

I'm getting around 400-430 a tank and this is baring in mind I've still gotta keep my revs down as I'm running in the new cam shells. So that's not me heavy boosting or anything.

Cheers guys

If getting 400-430 miles per tank is a bad thing. Then mines got issues too! ;s

[Adz_VRS]

If getting 400-430 miles per tank is a bad thing. Then mines got issues too! ;s

Lol well I'd expect to see higher than 30 mpg from this engine plus me driving in eco mode. I've got plenty of friends/ex customers of mine who have/had one of these cars and most achieve over 40 with ease and that's just local city driving. Of course my expectations may be too high

Had a good check of that wire before work today and it looks like it's been joined in two places.

It looks like another coolant flush and skoda thermostat is in order. Failing that a trip to the auto electricians :(

I want to try get this sorted asap as this may well have been the original cause of the head gasket failure. I don't fancy having to get that done again..... oh and I also replaced the water pump and timing belt with OE items... forgot to mention that earlier.

Is there any other bases I could check?

Thanks again guys for the support...

[coskev]

I think the wire your on about is the oil pressure switch for your low oil pressure warning light on dash.

Just down below the oil filter above the modine?

[Adz_VRS]

I think the wire your on about is the oil pressure switch for your low oil pressure warning light on dash.

Just down below the oil filter above the modine?

Yup that's the one. Ah well maybe a bit more investigation is required to sort this issue out. Thanks for the help though buddy

[KenONeill]

The thermostat never fully closes,so oil flows through the cooler all the time the engine is running,it just isn't fully open until the stated temp on kit.

I understood that to be how the unit you described works.

 

What I am asking is how the oil gets drained during cold running if a total shutoff thermostat is used.

[KenONeill]

Lol well I'd expect to see higher than 30 mpg from this engine plus me driving in eco mode. I've got plenty of friends/ex customers of mine who have/had one of these cars and most achieve over 40 with ease and that's just local city driving. Of course my expectations may be too high

Had a good check of that wire before work today and it looks like it's been joined in two places.

It looks like another coolant flush and skoda thermostat is in order. Failing that a trip to the auto electricians :(

I want to try get this sorted asap as this may well have been the original cause of the head gasket failure. I don't fancy having to get that done again..... oh and I also replaced the water pump and timing belt with OE items... forgot to mention that earlier.

Is there any other bases I could check?

Thanks again guys for the support...

Ah right; failed coolant thermostat or CTS should be throwing fault codes (VCDS time).

 

You mention fitting a new timing belt: Have you re-timed the injection (VCDS again) since? If not, then that could be part of the reason for your poor economy.

[coskev]

I understood that to be how the unit you described works.

 

What I am asking is how the oil gets drained during cold running if a total shutoff thermostat is used.

No oil cooler thermostat shuts off fully.who said they do?

[KenONeill]

No oil cooler thermostat shuts off fully.who said they do?

 

 

When it was mentioned about about the standard oil cooler(modine) they were referring to the fact they can rust internally and let your coolant and oil mix,so did you replace this or remove it totally?

If you've removed it that will be part of your problem,the modine helps get the engine upto temp aswell as cooling the oil when it's hotter than the coolant.

Ref the air to oil cooler you've fitted,even ones with a thermostatic plate allow oil to flow through the cooler at all times.

If they were totally blocked off at the thermostat then it opened when you were at high revs it could cause a big enough drop in oil pressure to knacker your engine.

So oil is flowing through your cooler at all times,it's just the thermostat is open fully at 80degrees or whatever they quote.

I would guess your thermostat is faulty or jammed open to be seeing the issues your having with the temp rising slightly when you boot it but then dropping down again

You did, at least sort of.

 

Or are you now denying that this statement implies a mechanism by which a volume full of cold liquid open at one end and closed an the other, and with the same liquid at a higher temperature flowing over its open end becomes drained?

 

I'll give you that a closed and suddenly opened orifice will cause a variation in oil pressure; what I'm trying to get my head around is how that variation can cause oil starvation, because it doesn't match with the fluid dynamics I studied at Uni.

[coskev]

What are you on about.

If your on about the bottom part of my post you've quoted I was referring to the coolant thermostat being stuck.

Nowhere in that post you've quoted have I said anything about the oil cooler being sealed/blocked off at any end.

Perhaps you should contact Mocal and offer your services,I was told by them that's why there thermostatic plates flow oil at all times.

[mogwye]

Gentlemen, this post has got out of hand, the original post was a simple question which the op was seeking a simple answer to.

 

But it's got into a hand bag fight over technical phrases which I am sure are not helping the op.

 

DB.

[fabianski47vrs]

Have you got a pic of where your oil cooler is fitted?

Need ideas /inspiration for mine.

Sent from my SM-G920F using Tapatalk

[Adz_VRS]

Thanks for all the input guys. I'm going to check the thermostat as a first port of call. Is it possible for this item to be fitted the wrong way round I. E against the flow?

I can also get pictures up over the weekend if it helps?

[coskev]

Thanks for all the input guys. I'm going to check the thermostat as a first port of call. Is it possible for this item to be fitted the wrong way round I. E against the flow?

I can also get pictures up over the weekend if it helps?

It should only fit one way,as the housing clips onto the thermostat.

If it was the wrong way around your car would be over heating if anything

[Adz_VRS]

Ah just a quick thought outside the box. I'm just fed up of this car right now. Haven't the spare time to be peeing about with it atm.

It's developed a horrible knocking now which I was informed was my duel mass however depressing the clutch and cycling through the gears on a drive doesn't really affect the noise. Revving the engine does when in neutral. Could it be that the cam guides are overly tightened as this noise was never present before the head work and it's only getting worse. Ive driven nearly 500 miles since the work. Grrrrrr if it's not one thing it's another:(