Car is spastic

[ange80rave]

Until i can get to a mechanic (thanks coronavirus). I am trying to self diagnose my car issues.

when i am driving my VY Supercharged L67 the car will get up to normal temp, If i turn on any accessories (lights, wiper blades, stereo, fan etc) the temperature guage rapidly fluctuates between normal and cold temp. Then the check engine light sometimes comes on.

I have noticed if i drive without any accessories on the temp stays at normal and the check engine light doesn't come on.

I have just replaced the battery thinking that was the issue but it didn't fix it.

Im wondering if it could be an alternator issue?

any help will be much appreciated.

 

[1985VK]

The car may be infected with corona virus... You may need to burn it... just kidding...

 

[_R_J_K_]

Likely to be a loom issue (wires rubbing through and shorting somewhere) or something like the wiper/indicator stalk.

If you've got a multimeter you can test the battery, should read just under 14 volts with the car on and not jumping up or down or anything like that.

 

[ange80rave]

OK Guys still no luck getting it to a mechanic, i have since worked out that when it gets up to normal operating temperature the fans will try kick in and thats when the temp guage drops back to cold then fluctuates between cold and normal temp. When i pull over and turn the car off and back on the fans kick in and the engine warning sound doesn't come back on?

any thoughts?

 

[the_boozer]

check the temp sensor and its wiring if the temp sensor isn't connect the fans will run and the cel will be on

 

[Fu Manchu]

Bleed the air out of the cooling system properly (not with the bleed screw)

 

[mechanic]

check the temp sensor and its wiring if the temp sensor isn't connect the fans will run

This is likely your problem.
A quick check will show the scan data on the coolant sensor will show -40 degrees as a default reading when the coolant temp sensor is open circuit.

 

[Trevor loves holden.]

Just replace the temp sensor they are cheap, then make sure the wire connection is good / no breaks.

 

[ange80rave]

Thanks guys will just replace the temp sensor, now where is it? I have looked at the back of the engine where the thermostat goes under the supercharger but can't see it?

 

[Utel67]

Under the thermostat housing.