vz thermal fans?

[henrytad]

I was having issues with my AC not working when the car was stationary. Turns out the Second fan was not kicking in. Closer investigation found that one of the pins on the 4 pin plug on drivers side of radiator was not making contact and had been arching. Fixed this up and AC works perfectly now

but the 2nd fan shouldnt be kicking in to make your aircon work, the 1st fan does the job, the second kicks in if your engine is extremely hot?

my issue is, after running the aircon for about 20 mins, the engine starts shaking as if it wants to turn off, at first i thought it was maybe the 2nd fan trying to kick in but not spinning but i discovered thats not it as the engine temp is still hovering at 90 degrees. i still havent found the issue and my mechanic doesnt know either. funny thing is the aircon works fine, its just this random shaking thats pissing me off

 

[muzammil.i13]

that info is directly from the genuine Holden workshop manual :idea3:

also - dont mind the typo's - was typing that late at night. Might have been easier to just upload a screenshot of the document

And bingo - old cars like the Ecotec would work in the way everyones mentioned above, ie turn the AC on and it'll kick in, but the alloytec is different. Theres a few threads on here where people have done all sorts of things to turn it on, from changing relays to shorting out relays to removing the fan completely and checking on a test bed.

Ultimately unless your car is overheating or your AC is about to blow its load, that fan aint gonna turn on and in all my time Ive only ever had that fan turn on once, which was in the Adventra after going up a hill towing a 2 tonne load, and that was after we parked for a pie and switched the engine off - I assume it was above 108 degrees as above.
Not even a track day in 40 degree temps got it going in the Acclaim because it never got hot enough to do it, nor in any of the other VZ Alloytecs there on the day

you made my life easier by posting Thermo fan operation, how ever my case is little bit different, I'm experiencing both fans to be running @108c +, once the temperature drops below 104c both shuts down, so here I'm missing stage 1 operation, could you guess the solution? maybe a relay? i don't think a faulty sensor or fan issue here as the sensor clearly reads the temperature just @ stage 1 one of the fan doesn't starts & it waits until temperature reaches to 108c which in turn directly goes to stage 2 operation i.e. both fans operating together.

 

[muzammil.i13]

that info is directly from the genuine Holden workshop manual :idea3:

also - dont mind the typo's - was typing that late at night. Might have been easier to just upload a screenshot of the document

And bingo - old cars like the Ecotec would work in the way everyones mentioned above, ie turn the AC on and it'll kick in, but the alloytec is different. Theres a few threads on here where people have done all sorts of things to turn it on, from changing relays to shorting out relays to removing the fan completely and checking on a test bed.

Ultimately unless your car is overheating or your AC is about to blow its load, that fan aint gonna turn on and in all my time Ive only ever had that fan turn on once, which was in the Adventra after going up a hill towing a 2 tonne load, and that was after we parked for a pie and switched the engine off - I assume it was above 108 degrees as above.
Not even a track day in 40 degree temps got it going in the Acclaim because it never got hot enough to do it, nor in any of the other VZ Alloytecs there on the day

I guess you’re wrong on stage one fan operation temperature set point (104) it is not @ 104 the fan will start but rather @ 108 for vz alloytec. Or is it that I’m missing stage 1 in my car