Anyone else with tunes have this issue? I got my XCal2 from my local SCT dealer who installed my 4.10 gears. Currently I am running the tune that come with the XCAL2. I will be going back for a custom dyno tune eventually but when I do go back I want the fan on temp. to go back to stock. Is there any benefit to have the fans on all the time? My temp. gauge isn't any lower compared to stock...

It's just kind of annoying everytime I pull up to an intersection or parking spot and the fans are running.

Thanks

 

Yep, actually I was more disturbed mine were never coming on! It's very hot here and when uploading from the Xcal you can switch to optional parameters and change the low speed fan temp up a few degree's. In my case, I put them down. I think mine is 190.

 

I think of the two options I would prefer them on than off, giving the ultimate outcome, but I guess it would get a bit annoying to be running even when not needed.

 

Mine is set for normal temp. I also have the e-water pump.

 

The stock CDC3 processor code's fan turn-on temps are 216 for low-speed and 228 for high-speed. I'm positive other codes' fan turn-on temps are similar, if not exact. Invariably, tuners will significantly lower these temps in their files. If I were a dealer, I would ask my potential customer what t-stat he/she intends on using so I could set my fan turn-on temps accordingly. For you guys with canned tunes, did your tuner ask you this? I'm not a dealer but have the software so I can monkey with my settings all I want, which I've done.

The reason why an engine doesn't run cooler with cooler fan turn-on temps is simple. You MUST replace your t-stat with a lower temp variant. This is THE controlling component to lowering engine temps as long as fan turn-on temps are lowered to correlate with the t-stat. Generally speaking, the fan turn-on temps should be slightly higher than the t-stat opening temp. In your case, the fan continuously runs because the engine temp will somewhat stabilize at a temperature higher than the t-stat setting. Because the fan turn-on temp is significantly lower, once it kicks on as engine temps rise, it will continue to run because the engine temperature will never get lower than the t-stat opening temp.

I used to run a consistent 200 degrees F with the stock tune and t-stat. I replaced my t-stat with a 160 degree F unit and lowered my fan temps to: 174 low and 180 high. On the hottest days (it does get hot in Tucson) with the A/C running in stop and go Tucson traffic, my engine runs a consistent 173-178 degrees F. On moderate days, it normally runs 167 - 172. I can state these accurate temps because I have a digital engine coolant temp gauge that's accurate to the tenth of a degree.

 

Yea I was going to say if the t-stat is 200, then the fans at 190 wouldn't do much except make noise.

 

My brenspeed tune does that, high speed is always on at operating temp. A bit annoying, but you get used to it. But also useless since they're obviously not helping the engine get cooler.

My Bamachips tune on the other hand is not so radical. The high speed fans are not on all the time, it looks like Doug is a bit more conservative on the fan settings.

 

Good information to know when considering a tune and a tuner to do business with in the near future here.

 

Noob question: What's a t-stat and how does it affect your engine temperature?

 

thermostat, opens and closes at a set temp that lets water flow thru the engine.

 

Good reply. I was wondering also why my fan was running way too long with my Brenspeed tune. I had Brenspeed make me a stock 87 tune so I could modify for my 4.10 gears while at the dealers for warranty. I noticed running my 87 performance tune the fan was running way too much so I checked the settings. They were at if I remember correctly, 196* low speed fan and 212* high speed. I then checked the settings for the Brenspeed stock tune and they were at 216* and 228* respectively. I then reloaded the 87 performance tune using the stock fan settings. I hardly here the fan anymore. just like it used to be.

I think the sct dealers should include a warning paper stating what temps each tune uses, or at least the default fan temps, to turn the fans on so we're aware of that parameter maybe needing personal adjustment before we even load the tune. Those like me running their cars well into winter don't need the fans trying to cool off the engine when we're trying to make heat.

 

Hypertech's t-stat is like 19 bucks. I'm gonna order one any day now.

 

Make sure you don't have the windshield defroster on. (not the rear window) It will run all the time if it is on. Same goes for the A/C.

 

Willie- Great answer in your post.

Question - Engine temp aside, I feel that when it's hot outside (98 or greater) in traffic, w/ the A/C system on, the exhaust manifold temps, alternator, rubber belts etc are all very hot. A little air from the low speed cooling fan cant be hurting anything. Agree?

 

Agreed. It can't hurt anything. The only downside is running the fan motor when it's not necessary. Note: With the A/C or defrost on, the compressor runs and for it to function properly, airflow across the condensor is mandatory. So the PCM will command either the low or high speed fan to turn on regardless of engine temp.

There's also a way to run both fan speeds manually. My pics show five switches (from left to right):

1) Low Speed Fan Switch w/built-in green LED with a secondary green LED above it.
2) High Speed Fan Switch w/built-in red LED with a secondary yellow LED above it.
3) Intercooler Pump Switch w/built-in green LED with a secondary blue LED above it.
4) Intercooler Heat Exchanger Fan(s) Switch w/built-in red LED with a secondary white LED above it.
5) Unused Switch w/built-in orange LED.

Each circuit has separate LEDs that serve a different function. Obviously the built-in LED turns on when the switch is turned on. The separate LED is wired to indicate that the fan motor (in this case) is receiving voltage. In other words, the separate LEDs turn on, not only when I manually flip the switch, but also when the PCM commands the fan to turn on.

Willie

 

I can relate it is annoying but it's completely normal if you have a decent tuner set it to show your engine temp and as long as you in the 180 to 214 degrees your more than safe.

 

I think he got it figured out within the last 10 years or so. Lol