High Speed Fan Operation

ourc6 · 08-02-2006, 10:05 PM

Got back from the Chevy dealer today after having the truck in for 2 days. The problem i am having is the high speed setting on the fan runs about 85% of the time. For instance if i put the AC on setting 2 after abotu a minute the high speed fan comes on without the recirc button pressed and will stay on . If i press the recic button nothing happens . Once i shut the system down the high speed setting will continue for about 2-4 more minutes before stoping. They tell me nothing is wrong and the relays and setting are ok. I just dont think so i have talked to mike about it and we both think something is not right but getting the dealer to see it is the problem. Any thoughts would be great i have a 05 with 2500 miles on it so she still is a newbie

Ps I am also getting alot of condensation around the blower vents by the radio

ggoat!!! · 08-02-2006, 10:13 PM

I have no clue. The high speed operation of my fan seems to follow no rhyme or reason. I have never witnessed it come on at the high speed setting when I press recirculate. I don't have an overheating problem, and I have heard my fan kick on at high speed when just sitting/idling, but as far as the recirculate feature supposedly turning it on to high speed, mine doesn't-even after 5 minutes. I've got Mike's fan installed so I'm not worried. I know the original will fail, its just a matter of when. Its alot easier when you accept the product you buy for what it is (a GM product) before you buy it. As long as you don't have any real quality expectations, then you'll be happy with the truck. You just have to know what it is that you're starting with.

By the way...I think your problem is a simple stuck relay. Relays commonly fail in vehicles, particularly high temperature environments. I can't recall the 20-30 times in the last 5 years that relays failed in my various vehicles causing all sorts of headaches. I always carry a few extra. I wouldn't expect the dealer to try to find anything wrong as long as the fan comes on in any way. BTW, where is your engine temperature during all this?

Jeff

ourc6 · 08-02-2006, 10:22 PM

I to have mikes fan but took it out to bring it to the dealer, As for the temp without mikes fan it runs at 210 driving and up to 235 to 240 when at a stop light with no AC on with it running it gets to about 225 at a light them comes back down once in motion , I have to put mike fan back in to keep it at one temp but want to get this problem fixed if there is one,
thanks

Jerry

ggoat!!! · 08-02-2006, 10:31 PM

Hi Jerry...you definitely have something wrong.

Mine never goes above the "1" in 210, even without Mike's fan. I spent 4 hours in stopped traffic in NYC with the A/C on, and the temperature did not budge. Even in the hot super humid smothering heat of the south my temperature never moved above the "1" in 210, even after performance driving, sitting in traffic, etc. Mike's fan is great insurance, but honestly my temperature gauge stayed exactly the same after installing it. (But I wouldn't have the truck without it! Thanks, Mike!) Your fan is coming on at high speed, probably like it is supposed to do, because your engine is running hot. Its impossible to tell the real temperatures you're referring to since the gauge doesn't have enough calibration marks. Anything is really a guess. So, you're probably at 235 (the temp the fan goes on high speed at I believe) before it looks like you are. The fan stays on since its trying to cool the system down, even though the gauge might "look" (since you have to guess) like you are lower than that. With the higher thermostat in the 06's at least, the engine should stay at 210 if the cooling system is working efficiently. Since your high speed fan stays on TOO LONG then I would assume your temperatures would be LOWER than normal (due to the fan actually cooling something) than HIGHER. That's if there were some cause other than the heat of the engine that was causing the fan to switch to high. But, since your temperature is actually high, that pretty much rules out an electrical relay problem. The fact that your temperature readings are higher tells me that the fan is doing its job, but something else is causing your engine/transmission to run so hot as to force the fan on at high speed so early. I'm sorry to say I don't know what that would be.

Good luck, and sorry to hear of your problem...
Jeff

Mike in AZ · 08-02-2006, 11:47 PM

I may have an answer for ourc6...

Look closely at the last paragraph in the left column.... It has to do with A/C system pressures.

You may be getting an improper influence from one of the pressure sensors in the A/C system. If your sensor for the high pressure side of the system is bad and reading higher than reality, it might be driving the fan to run at high speed.

You might be able to get the dealer to check the A/C system pressures with the tech 2 while operating normally.

As for ggoat - - - - - when you have the A/C on, it drives the fan to low speed operation. This will have your system running on the 210 mark.... If you want to see the temperature swings, pull the fuse from the Aux Fan and turn the A/C off. Go find a little stop and go traffic in this configuration. You will then be able to see the "natural" temperature swings that make everyone crazy. When you have had enough, either put the fuse back in or turn on the A/C and it will bring the temp down to 210.

Regards all,

Mike

ggoat!!! · 08-02-2006, 11:57 PM

Thanks Mike...

In all honesty, I figured he was talking about his temperature swings with the A/C on; I couldn't imagine anyone driving around this time of year with the A/C off, and yet people are still commenting on the temperature swings. So, I just assumed that the swings were with the A/C on. I'm sure the temperature would rise without the A/C turning the fan on "low", since the fan doesn't come on until 226 I think. But, like I stated, I was under the assumption that the temperature swings were still occurring with the A/C on, which would indicate something in the cooling system isn't working efficiently, or something is producing excess heat; especially if the fan is running on high TOO often.

Respectfully,
Jeff

bobmorasko · 08-15-2006, 12:28 AM

I am considering purchasing Mike's auxilliary fan. I, however, have a few questions:
Why is it that everybody wants to run the engine temperature at or below 210 degrees?
Are there studies that demonstrate GM's fan settings will harm the engine?
Why hasn't GM provided a fix if this will harm the engine?

hdflstf · 08-15-2006, 12:32 AM

Quote:

Originally Posted by bobmorasko

I am considering purchasing Mike's auxilliary fan. I, however, have a few questions:
Why is it that everybody wants to run the engine temperature at or below 210 degrees?
Are there studies that demonstrate GM's fan settings will harm the engine?
Why hasn't GM provided a fix if this will harm the engine?

Main issue as I see it is that there are some pretty big temperature swings as designed by GM. The computer will keep you from destroying the engine. I'll likely get some heat for this so I put my flame suit on just in case.

WOW_FCTR · 08-15-2006, 08:40 AM

Quote:

Originally Posted by bobmorasko

I am considering purchasing Mike's auxilliary fan. I, however, have a few questions:
Why is it that everybody wants to run the engine temperature at or below 210 degrees?
Are there studies that demonstrate GM's fan settings will harm the engine?
Why hasn't GM provided a fix if this will harm the engine?

In my '03 the engine stays at 210 almost ALL of the time....A/C on/off, me moving, stopped, etc. with just the OEM fan. The only reason I would consider Mike's fan is that I know the OEM fan will fail (it has once already!) and when the fan fails....I can't drive it....it WILL over heat. So it looks like the SSR is supposed to operate at 210 (see other posts about what the low speed/high speed fan temperatures are set to).

I think people with the 05-06's see much more of a temperature swing and would like to see NO swing. This is my opinion and I'm sticking to it

shiftz33 · 08-15-2006, 09:34 AM

I keep seeing posts stating that the stock setup never gets above 210 on the dash temp gauge.

If you are obtaining a temp reading of 210 or below with a stock fan and stock fan programming, then you MUST be driving your SSR in situations where you move your SSR enough to allow the natural airflow to keep the temp down OR you're driving with your A/C on which drops the on temp for the low speed fan.

Stock fan settings (less than 35 MPH):

A/C off:

Low speed on: 226
Low speed off: 219
High speed on: 235
High speed off: 226

A/C on:

Low speed on: 185

The outside temp has A LOT to do with this as well.

My travels in the Sacramento, CA area during the summer months (record setting this year), have shown that the stock fan with the stock fan settings does not keep my SSR temp under full control (read middle range of temps allowed). The engine bay gets heat soaked quite easily in this area and the temp of my SSR would often go to the 235 level. With Mike's aux fan, the 210 range would be seen for quite some time, but after the extreme heat and sitting in traffic cooks the SSR for a while, the temp would begin to raise further.

My fear with the OEM puller fan is that it would fail during any one of my trips with my SSR. Mike's aux fan was doing a great job at trying to reduce the need for the OEM puller fan, but the need for a reliable puller fan was still there.

I installed the Diablo Predator "91 Octane tune" a couple of months ago. It has reduced "on temps" (sorry no chart for this one - high speed appears to be around 215) for the puller fan. It showed me that it was possible to keep the temp lower than 235 in my SSR if the fan was given the command to do so. That's when I purchased Mike's replacement puller fan (JimG's fan would do as well) for my SSR. I saw an immediate improvement in the temp control of my SSR with Mike's new puller fan in place!! Plus, Mike's aux fan does not have to run like a "mad fan" after shutdown to pull out all of the excess heat like before. The aux fan runs maybe once or twice and it's done.

I guess I'm just trying to say there are situations where a replacement fan makes sense. The GM (VW) OEM fan has shown itself to fail (even with the updated design - filter for the motor brushes). Getting another GM (VW) fan (without changes to its design) is only pushing back the point in time when you might experience a failure of the OEM puller fan.

With Mike's aux fan, Mike's puller OEM replacement fan and the Diablo Predator tune (with reduced on temps) in place, I can finally say my SSR does not go above 215 (with A/C on or off). That's definitely not a statement I could make before.

Mike's pusher fan (aux fan) - great to help reduce puller fan use and takes heat out of the system after engine shutdown.

Mike's puller fan (JimG's too) - replacment for OEM (VW) fan that will fail at some point

WOW_FCTR · 08-15-2006, 01:01 PM

Quote:

If you are obtaining a temp reading of 210 or below with a stock fan and stock fan programming, then you MUST be driving your SSR in situations where you move your SSR enough to allow the natural airflow to keep the temp down OR you're driving with your A/C on which drops the on temp for the low speed fan.

I swear in temps 90+ degrees, at a dead stop, my temp does not go above 210. (now maybe I didn't fully "unload" my Diablo tune like I thought I did and that does it....although I never messed with any temp changes, it would have had to been done as part of the standard 87 Octane tune.)
I look at the temp guage all of the time because it did have a water pump go and the fan failed, so I've overheated twice already....and other than those 2 times, I haven't see the temp go above 210. (just as a side note...mine is an early '03)

Joe Schuhriemen · 08-16-2006, 02:30 PM

Quote:

Originally Posted by WOW_FCTR

I swear in temps 90+ degrees, at a dead stop, my temp does not go above 210. (now maybe I didn't fully "unload" my Diablo tune like I thought I did and that does it....although I never messed with any temp changes, it would have had to been done as part of the standard 87 Octane tune.)
I look at the temp guage all of the time because it did have a water pump go and the fan failed, so I've overheated twice already....and other than those 2 times, I haven't see the temp go above 210. (just as a side note...mine is an early '03)

The 05/06 engines are hotter in more ways then one.

GSchurg · 08-16-2006, 03:17 PM

Unfortunately mine is currently waiting a fan (national back order). My temp pegged out as I was stuck in interstate traffic (not moving). The service advisor said that it wasn't hurt because it would shut the motor down first? I didn't notice any warning chimes nor any info on the display.

WOW_FCTR · 08-16-2006, 03:26 PM

Quote:

Originally Posted by GSchurg

Unfortunately mine is currently waiting a fan (national back order). My temp pegged out as I was stuck in interstate traffic (not moving). The service advisor said that it wasn't hurt because it would shut the motor down first? I didn't notice any warning chimes nor any info on the display.

When mine over heated, I definitely got chimes and lighted warnings!

(I did drive my truck 40 minutes yesterday and then left it parked in my driveway running for 5 minutes. The fan was on, but the temp was it's usual just below 210. It was 93 degrees out....)

shiftz33 · 08-16-2006, 09:14 PM

Quote:

Originally Posted by WOW_FCTR

(I did drive my truck 40 minutes yesterday and then left it parked in my driveway running for 5 minutes. The fan was on, but the temp was it's usual just below 210. It was 93 degrees out....)

Then you must have had the A/C on to have the fan on at any speed at that coolant temp. The stock fan settings without the A/C on would not have had the fan on at all.

WOW_FCTR · 08-17-2006, 08:07 AM

Quote:

Originally Posted by shiftz33

Then you must have had the A/C on to have the fan on at any speed at that coolant temp. The stock fan settings without the A/C on would not have had the fan on at all.

The A/C was not on....so maybe I never unloaded the Predator tune like I thought I did, but in any case........the temp does not go above 210 in any situation.

shiftz33 · 08-17-2006, 08:38 AM

Quote:

Originally Posted by WOW_FCTR

The A/C was not on....so maybe I never unloaded the Predator tune like I thought I did, but in any case........the temp does not go above 210 in any situation.

Very cool!

My 05, with the Predator tune in place (no A/C on), has the radiator fan (puller) on around (at or slightly below) the 210 level as well. Since I have Mike's aux fan installed as well, I hear both fans on at this level. I'll see my temp gauge around the 210 mark as I pull into the garage, turn off the engine, I'll hear the puller fan turn off and about 2 seconds later Mike's aux (pusher) fan turns off as well (means it was not on due to the temp settings for this fan). With the engine being kept at or just below the 210 mark, Mike's aux fan only rarely comes on after engine shutoff since the temp conditions that would trigger its after engine shutoff running have been avoided.

When I still had the OEM puller fan in place, the engine temp was not as well controled as it is now (same fan settings). I can even open up the hood after driving and notice a lower temp to the egnine compartment. The shrouded puller fan seems to have made a major difference in my SSR's overall temp. The hills I drive on push my tranny fuild temps a bit which in turn raise the temp load on my radiator as well.

lukyboy · 09-28-2006, 06:20 PM

Hey Mike, I was wondering if you could tell me why my 03 has started running hotter than normal. I'm 4 hours West of you in the Imperial Valley, so we've got almost identical temps to Phoenix with a little more humidity. We've done fine all summer long (we bought the R in late May this year) but lately it's started to hit the 2 in 260 when we're sitting in the drive thru or in traffic, even with the a/c on high and recirc. My wife had this problem last week and called me. She turned the heater on full blast (like in the old days) and the temps dropped quickly, although I suspect it helped that right after, she got on the highway and up to speed. My problem with this is that it wasn't doing it when we got it. It had 3500 miles when we got it and it now has just under 12000. Does this sound like a fan failure, or is something else coming into play here? I can definitely hear and see the fan running at two different speeds (when it's running and when I turn on the a/c). Obviously we're through the worst part of the summer, so I would expect it to be running cooler than before, but it's doing the opposite. Any help will be greatly appreciated.

hdflstf · 09-28-2006, 06:30 PM

Quote:

Originally Posted by lukyboy

Hey Mike, I was wondering if you could tell me why my 03 has started running hotter than normal. I'm 4 hours West of you in the Imperial Valley, so we've got almost identical temps to Phoenix with a little more humidity. We've done fine all summer long (we bought the R in late May this year) but lately it's started to hit the 2 in 260 when we're sitting in the drive thru or in traffic, even with the a/c on high and recirc. My wife had this problem last week and called me. She turned the heater on full blast (like in the old days) and the temps dropped quickly, although I suspect it helped that right after, she got on the highway and up to speed. My problem with this is that it wasn't doing it when we got it. It had 3500 miles when we got it and it now has just under 12000. Does this sound like a fan failure, or is something else coming into play here? I can definitely hear and see the fan running at two different speeds (when it's running and when I turn on the a/c). Obviously we're through the worst part of the summer, so I would expect it to be running cooler than before, but it's doing the opposite. Any help will be greatly appreciated.

Could be a blown fuse or other problem but most likely it's the fan.

joel · 09-28-2006, 08:04 PM

If you have verified that the fan is functioning normally on 2 speeds and you have checked the coolant level (preferably when cold, CAREFUL), your next stop should be your friendly Chevrolet dealer (assuming you have a warranty).