Radiator Fan Control / Grille Block

[ssnsvibe09]

My vibe AKA Matrix has a Fan Control Module that I have just recently started to monitor from inside the car with a light wired across the fan power leads.

It will turn on at 95c(203f) and the light will remain on all the way up to 100(212), but no higher which initially I found odd.....

So on went the volt meter across the lamp inside my car, and two trips at 60 miles each I have found the following data.

Temp - Voltage
95 - 4.23v
96 - 4.56
97 - 6.23
98 - 7.91
99 - 9.06
100 - 9.06

I have yet gone past 100 degrees and the fan has not had full battery voltage. This by the way is with all of my grill blocks installed flying down the highway at 60 mph with a frontal wind of 20 mph plus.

This i feel is a very large advantage for engine temperature control. once it goes to 95 degrees it is near constant unless I off the throttle. I have observed so major gains WRT mileage and actually expect to break 800 km or 500 miles shortly, maybe this tank.

Intake air is about 10 degree C above ambient (11 this afternoon) at highway cruising and goes up to well over 20 degrees in light load conditions.

There are times when intake air is at 36 degrees (98), where I think is the greatest benefit and very likely the reason for the big numbers.

I did tinker with the grill blocks before I got my OBD scan tool, which now explains my spike in mileage then.

[ecomodded]

Your engines thermostat is around 170 - 180 F degrees , your car is running Hot, If I'm not mistaken ?

it may be a fault in the temperature controller for the fan or the fan itself, I think you need to apply 12v to the fan and listen if it speeds up it should be fine, then check the temp controller out where ever that is on your car or fan...

[ssnsvibe09]

All of the temperatures above are celcius with (farenheit in brackets).

With the grill blocks off it would just barely maintain 85 (185f). My thermostat, I believe is actually 85(180f) Between 85(180) and 90(190) it take a little while to climb up which sort of supports my claim....and the aftermarket parts folks.

Something makes me think that the folks at Toyota like to manage the engine temperature at 95(200) to 100(212f) with the fan speed. So far my grille block achieves this easier in cooler weather, and the fan / radiator has not gone to full speed and capacity.

Another point of interest is that the radiator and fan unit for my 1.8L is the same as the one for the 2.4L GT engine that has 30 more HP. Therefore my radiator is also overcapacity which is also dampened by the grille block.

[cbaber]

The fan shouldn't be on at highway speeds. But if the fan can handle the cooling with the full grill block, you just have to see if the MPG improvements offset the increased alternator load with the fan running all the time. Depending on the power it consumes the fan could be using 1-3 mpg.

I think the ideal approach is to use smart ducting or just small inlets to allow better cooling, but still a significant aero improvement over stock. Only testing will tell which yields the better net MPG improvement. Keep us up to date.

[ecomodded]

I forgot.. the fan was just on mid speed as your not nearing the upper temperature limit, I checked and upper temp with out boil over is 230-240* on a hot day say towing a load or up a hill etc.
I am pretty sure a hot running motor would be thinning and cooking its oil.
You could also put in a 160* thermostat for summer

I became a fan of cool running engines when i got my diesel its cool running and subsequently gets 20,000km between oil change interval, which i actually stick to as bad as it sounds..

[ssnsvibe09]

Yeah I have not hit my upper limit yet. I am assuming that 9 volts is not the peak output of the fan controller. If and when I do, I will be pulling over and removing one of the grille blocks they are only held on with four screws and wingnuts.

I confidently tolerate 100(212), as long it peaks there, but if it becomes sustained and peaks much higher I intend to allow more air in manually.

I am running my car with Mobil 1 AFE 0w-5 engine oil, I buy it on sale and change it at 16000, saving time and money, the oil worked great this winter in my subzero temperatures.

I have enjoyed one big change in MPG so far and the next tank will be telltale ... might be very close to 40MPG(us), if I can keep the trips long, warm and below 90kph.

My car is like a sail above 90kph, lol. I actually get better mileage off the highway because my car has DCFO that is very sensitive to no load conditions that I am getting really good a taking advantage of.

[ssnsvibe09]

So far, so good.... I did manage to peak the temperature at 102(215) at 100kph pushing directly into 42 kph winds. The were times when I was at 100% load up a gentle hill. I did not get to monitor voltage on the meter, unfortunately it was preoccupied with other jobs in my garage and i forgot it. I you take a peek at my fuel log, I manage to get even better mileage than the last time.

I am sure that I will have another opportunity to verify fan operation and will provide data.

[ecomodded]

Your mileage is improving -that's the right direction- Good job, the longer distance fill ups are more tell tale as they factor out a lot of the noise that you get with the small fill ups. If you can wait to run the tank through before taking mileage you will be more accurate, It takes longer but it gives you lots of miles to be frugal with and determine your tank average , or your cars true mpg.

[ssnsvibe09]

I only report average mileages of complete fills. A tank of gas only lasts 3 or 4 days of commuting. Wind and temperatures change too much on the coast here for quality A-B-A testing. Yesterday for example I left work at 10 degree C and got home to 20 degrees but the winds went up by over 40 kph. and that is only within an hour and 100 kms of driving. Plus the only truely flat roads in Nova Scotia belong to aircraft runways. I posted an image or GPX plot of my commute, some time ago. I am not sure how it would compare to driving TCH or route 19 on your island

[ConnClark]

Just an observation in this discussion.....

I would suspect your fan controller is using pulse width modulation i.e. All the way on and all the way off. Otherwise it would be very inefficient electrically and hard on the electric motor. Your volt meter probably can't react quickly enough to the pulses so its showing a rough average.

However the volt meter can still be used to show a change in power delivered to the fan motor