Coolguy@18

Hi there, thank you for the reply. There is no low coolant warning, temp gauge is at 90. The red warning will show on the cluster for about 1 sec with loss of power until light goes out. The warning states engine over heating. If I unplug the plug on the coolant bottle I will get a red warning on the cluster but it's a different message, this will state Check Coolant, so I know it's not a low level issue. TSB 1 - Dont think this is my issue as it's not a level issue. TSB 2 - Dont think this is my issue as I think people report of the warning along with the temp gauge going past 90. Mine will display message but temp gauge at 90 plus a new revised pump has been fitted. The coolant system as also been bleed via diag machine etc Any ideas??

So far I have tried live data on. Oil temp. Coolant block temp. Rad out let temp. Intake temp. Intake charge temp. Alt temp. Turbo temp. Exhaust up temp. Exhaust down temp. ECU temp. Nothing will change upon this fault. Do you know of any other sensor that can cause this message?

There was no original fault so to speak. All started with this red warning (engine overheating) and engine stutter at same time as warning. We replace the pump as it was a revised unit and new temp sensor. This fault has started since any part replacement but has but has not fixed the intermittent issue and with no code as well it's hard to pin point it..

Nope the common bag issue is fine, coolant system has been flushed as well to make sure. This really seems like an electronic issue to me..

Yep, even done a static drain but no different. I would like to think I am missing a intermittent temp sensor some where but think I have got them all. The red warning is for the engine cooling system overheating so you would think coolant temp. There is no codes for any temp senor faults though?

Yep using a couple of high end diag software 1 being full VCDS. The list of temp options I gave was just an idea but I had loaded up the charge cooler and again in spec and when fault happens no spike or change in temp??

Hi mate, No faults logged in any ECU, I even had live data for EML warning and this will not change upon the overheating warning, dont think it is showing the error for long enough for it to light a code. So strange?? I also looked on the wiring diagrams and I can only see one coolant temp sensor for this engine. Seems like a software glitch? It's strange when it happens the engine will lose all power for a second until light goes off?

Hi there, definitely no air lock in the system.

Also the temp gauge its self will rise to 90 and stay there, when I get the warning the gauge still stays at 90, if this helps.

Hi guys, hope you can help to see if you have come across this issue before? We have a 2015 mk3 Octavia with the 2.0Tdi engine (CRMB) and every now and then when driving the car will hick up (like it's trying to go in limp mode for 1 sec) and a red warning will display for a sec (sometimes not long enough to read) stating please stop engine overheating! Now the water pump has been replaced with the revised genuine pump, the coolant temp sensor has been replaced genuine. There are no codes stored in the ECU. With live data on the car such as: Coolant temp Rad temp Oil temp ECU temp Intake temp All are in spec and when the warning displays there are no temperatures spikes! Any one come across this? Ryan

Yes there will be positive pressure but I am worried about the amount that's all. If I take my hose off from the pcv and hold hand over nipple, after 3 secs let hand off it just out so much air, seems too much and my MAF reading is very high

That's correct, the hose from the pcv valve is connected to the intake hose from the intake manifold which will cause neg pressure (vac), this should then suck the gas from the gasses in the rocker (That came from the sump) back into the manifold to be burnt off etc. My question is most engines have a ballance of pressure close to 0, the pcv will then operate causing a slight vacuum to draw the gasses out, and normally if you remove the oil filler cap the engine will hunt a little (as vac loss and extra air enter intake etc) but you should feel a slight vac from the oil filler cap once removed. This one is blowing and if I cover up for 30 secs and release my hand it will shoot out a huge amount of compressed air, this can't be right?

Hi guys, any one had chance to remove thier oil filler cap while engine is running to see of they do have air pressure??

Hi guys, ok so if I remove the pcv pipe engine seems to run a little better. If I use my hand to block off the plastic tit to the pcv valve it's ok for a short while, if I hold my hand over it for more than 30 secs then remove my hand it will blast out LOT of compressed air, it's like the build up is a LOT. A thought a pcv is to suck only and not have volume of air being forced though?

Hi guys, I have a diesel and trying to solve a EML issie. I have noticed that if I remove the oil filler cap or dip stick there is NO change in engine tone. If I remove the oil filter cap there is a LOT of air pressure behind it? It's enough where if I twist it undo with engine on it will lift the cap off. I am sure there is ment to be a vacum where if I lift the oil filler cap off there should be some suction?? Any idea or can u guys remove you oil filler cap and see if yours does the same?