A/C Off Due to High Engine Temp

[Markf19]

2014 VF International
Due to coolant leaks I recently had the Thermostat and Water Pump replaced. Trans out to fit thermostat all up $1365. Car was running fine for 10 days after repairs.

Day 10 and 10min from cold start I get a dash warning ‘A/C off due to high engine temp’. Temp gauge is dead, not working. I’m in the country 100km from home, so pull over, shut engine down, auxiliary fans running.

I call the RAA, all coolant levels perfect. Car gets towed to nearest workshop. This was a Friday so car doesn’t get looked at until Monday.

When they look at the car no warning evident. They run some checks, bleed the system and find some air, they also replace the cap. They test drive with scanner car is running cool 70 degrees, should be around 80. Charge me $260 and send me in my way.

Drive around for another 10 days without issue then same **** happens! 10min in from cold start same warning and temp gauge is dead. It’s a Sunday so I just drive home because engine doesn’t feel hot.

Monday morning start car from sitting overnight, same warning on start up and temp gauge dead. I ring the original repairer and drive the 10min and drop the car off.

They replace the temp sensor charge me $156. Car runs fine for the rest of the day. Next day 10min in from cold start same friggin **** again!

No-one knows WTF is going on and I never had this issue prior to the cooling system repairs. Hence why I’m posting here.

Any thoughts appreciated as this issue keeps costing me $$$ and pissing me off big time!
Cheers, Mark.

 

[HarryHoudini]

Sorry to hear that,been there with other cars i have owned,one turned out to be the thermostat not opening properly,bad batch/NOS,at least we didn't have to take the Tranny off to fix,VN. Another car,Datsun,was a cracked head.

If having no joy with the original mechanic i would consider taking it to a major Holden Dealership,expensive but too good a car to cook the engine.

 

[Skylarking]

I’m old school so I always want the old parts tested to check whether they are indeed faulty before the are replaced. And ideally I’d test the new part before it’s installed, especially if it’s in a location that’s costs a lot of hours and $ to get to…

The original thermostat should have been suspended in water along with a thermometer and the water heated till the thermostat started to open. If it started to open at the required temperature it ain’t faulty and can go back in… Similar logic can be used to test the old water temp sensor where resistance can be checked as the water is heated and compared against the specs… Doing such ain’t rocket science

A good mechanic will always check old part to confirm it’s faulty before firing the parts cannon.

As to what’s wrong, engines can only overheat if

1. the coolant can’t circulate efficiently through the system because of a stuck thermostat (even new stuff can be faulty) or corroded water pump fins (not likely as it’s been replaced).
   
   
2. cooling air can’t pass through the coolant radiator fins because of some external blockage to the radiator or a/c condenser at the front of the car (and easy look, see and clean).
   
   
3. coolant pressure can’t build up because of a leak (head gasket leak, loose hose clamp, water pump gasket leak, etc). The radiator cap a is also known weakness in the VF but it’s been said that you should only ever use a OEM cap (hopefully the replacement is a factory cap).
   
   
4. the system hasn’t been bled correctly and air is still in the system (where the temp sensor can suddenly drop as an air pocket forms around the sensor itself).

Best approach is to take it back to the original mechanic and get them to correctly bleed air out of the system. The following thread highlights how to flush the system correctly and it’s a good idea to read it all in its entirety

https://forums.justcommodores.com.au/threads/vz-ve-vf-alloytec-cooling-system-repairs.279976/

Have the original repairers also perform a pressure test of the cooling system both when cold and when hot.

I‘d also give them the $260 bill for bleeding the system and changing the cap, maybe the $156 bill for changing the temp sensor (but I don’t believe it was faulty). They should refund those costs if they are a half decent business as they could have replaced the thermostat in a more cost effective manner than dropping the trans.

Good luck with it.

 

[Sir Les]

Commiserations Mark -- sounds like you've had a very frustrating time lately. I'd be interested to know how many kms your car has done, and where exactly the original coolant leaks were coming from to warrant the thermostat and water pump being replaced.

From your description of the symptoms it seems to me -- and remember, I'm no mechanic -- the problem is more electrical/electronic than mechanical. After all, the coolant doesn't actually get too hot, does it? Yet you get a warning message and the temperature gauge goes dead, which in itself suggests an electrical problem. Maybe some cable harness/connections were disturbed and/or not properly restored when the transmission was replaced? Electrical connectors can get very touchy as the plastic around them ages with time and heat.

In your place I'd take the car to an auto electrician to check what fault codes are present, and to try to trace the cause of the intermittent dead temperature gauge, as I think that could hold the key to your problem. Unfortunately to us laypersons, the mysteries of the BCM (body control module) and PCM (power control module) are unfathomable, and yet those two black boxes control almost every feature on your vehicle. Good luck!

 

[Fu Manchu]

I’ll bet there is still air in there.
If I were you, I’d spend $25 on a bleed kit on eBay and take an hour on Saturday to do what workshops don’t do properly.

If you don’t want to do that, I’d be topping up/checking the reservoir after every trip and if it’s a long trip (30-60mins) stop and check the level. Top up as required.

As air is expelled, coolant is drawn in. If all the coolant goes in and there’s no more left, air goes back in and things get hot.

 

[Fu Manchu]

The bleed funnel kit:

https://www.ebay.com.au/itm/3746131...VTSobbORpi&var=&widget_ver=artemis&media=COPY

The bleed procedure in here:
https://forums.justcommodores.com.au/threads/vz-ve-vf-alloytec-cooling-system-repairs.279976/

 

[Skylarking]

The bleed procedure in here:
https://forums.justcommodores.com.au/threads/vz-ve-vf-alloytec-cooling-system-repairs.279976/

Already linked your cooling system repair thread in my post #3 above but the OP has gone dark after he first posted maybe he’s still pushing his car home, hope not

 

[Fu Manchu]

I see.

 

[Forg]

Already linked your cooling system repair thread in my post #3 above but the OP has gone dark after he first posted maybe he’s still pushing his car home, hope not

Mark F19 has gone into stealth mode ...

 

[Skylarking]

Mark F19 has gone into stealth mode ...

Via the truth, we've scared another one away