Fan clutch and water pump cause- what are your thoughts?

Realism

Original poster
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Nov 25, 2015
179
Idaho
Well folks, I mentioned briefly during a different topic about having sluggish acceleration, reduced power, and sucking fuel. Warm and clear enough outside to start poking around at this issue. Must be leaking power steering - only had just the bare tip of the stick wet.
I first was thinking possible exhaust restriction since two years back I had a bad thermostat (stuck open) that was let persist for about 1,500 miles. Couldnt get the pre-CAT O2 sensor out with end wrench, so hit it with PB and will try it tomorrow. I did hook up a vacuum gauge to the intake and watched it stay steady at idle and revved to 2000 RPM and held to see if I started losing vacuum, which would help point to an exhaust restriction. Vacuum level didnt drop, so may not be exhaust restriction, will still pull the O2 sensor to double check on that anyways.

Moved on to checking Transmission Fluid - Not much on low side, maybe could use a quart. Does need to be changed though, it is that cherry red color so it's getting close.
Checked oil - seems a bit lower than what it was when I did oil change last year. Checked the intake resonator and felt heavier at the front than what I remember. The crankcase ventilation pipe was showing a decent amount of oil through it, back of resonator was clean, but where ventilation pipe connects I could see some oil residue and some of that milky oil gunk from the short trips during winter. Checked TB and it looks pretty good, not in need of cleaning it seems.

Drive belt is getting there for replacement. While inspecting that I gave the Fan a few turns to test its resistance. Pulled up on it from the top and only slightly saw some movement, did it from the side and oh buddy, I think we may have found the cause of the sluggish acceleration and fuel consumption.
Im not a trekkie fan, but I think Dr. McCoy can sum this one up for me. "He's dead, Jim."

What do you guys think? Pretty bad shape huh

 

Mooseman

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Dec 4, 2011
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Realism

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Nov 25, 2015
179
Idaho
Used a rolled up harbor freight ads magazine, but felt like had to apply a bit of pressure to get it to stop spinning. Could feel little "tugs" i guess you could say, nothing big and super noticeable jerking. Engine temp when I did this was at 190 - 210 according the the idiot gauge inside. Figured it was close enough to full temp.

 

Mooseman

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Dec 4, 2011
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I'm not too convinced it's working that well. Tap into the white wire and put +12V on it. She should eventually lock up all pull air hard.
 

Realism

Original poster
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Nov 25, 2015
179
Idaho
Do you mean splicing into the white and running a wire straight from battery? lock up all pull air hard?
 

Mooseman

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Dec 4, 2011
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Ottawa, ON
Or jumper the fan relay. That would be easier.
 

Realism

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Nov 25, 2015
179
Idaho
Ah okay, I get you now. Jump it to give full 12v and see if it does the same, check if its getting full power sent to it.
 

Realism

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Member
Nov 25, 2015
179
Idaho
Just to make sure, With the relay pulled out, I am jumping from no.2 (run start from #20 fuse) to no.4 (PWM power output to fan clutch) ? *Ignore that, found answer from other site that Roadie posted

Got it up to operating temp, checked the voltage from fan plug white to ground on battery. Showed me 14V. Pulled out the relay and jumped no.2 (run start from #20 fuse) to no.4 (PWM poewr output to fan clutch) with paperclip and aside from the clicking that sounded like ac compressor (normal sounds to me at this point), there does not appear to be a change in the speed of the fan. Could still stop it like before with newspaper and got the same little barely tugs. It's never sounded jet engine loud. Come to think about it, I do recall two years back during the hot summer starting it up and for the first little bit I could hear the fan being loud before it dropped off, same with feeling more air being pushed when the hood was open during that time back then. Not as much air feeling pushed i think now.

Thinking it failed or getting close to it in the off position? Never had an issue overheating, even on long trips
 
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Mooseman

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Dec 4, 2011
25,257
Ottawa, ON
It will cause issues in very hot conditions and poor A/C performance while idling. For a replacement, Hayden is the preferred brand. Dorman are junk. Another option would be to get a tune at limeswap for $99 to turn off the fan codes and get the 2008 thermal clutch. Total would be about the same and you would also get the benefit of the tune.
 

Realism

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Nov 25, 2015
179
Idaho
LMAO. Poor AC at idle says he to the man living in Idaho's desert, don't I know it. Tepid air at best, kind of figured the compressor was going when it would do that. got cold when moving.

Not sure what is in it now, but judging by the grooves on the nut, and the fan blades this isn't it's first rodeo.
The limeswap tune, is that just for turning off any fan codes? What is different about the 2008 model?

Was really hoping I wouldn't have had to attempt this for a while. Least it's not winter :smile:
I've read a number of posts on changing out the WP and fan clutch, some give different tools. What do you think is the better tool to use for that nut
 

Mooseman

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Dec 4, 2011
25,257
Ottawa, ON
That would be the clutch causing that for sure.
In 2008, GM realized what.a POS that electro-viscois clutch was and went back to a good old fashion thermal only clutch. The time can also adjust other things along with turning off the fan CEL codes like shifts and removing torque management which makes it feel much more responsive. It's worth it.
 

Realism

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Nov 25, 2015
179
Idaho
Went to the limeswap site, didnt see much of what all can be done for customizing a tune. I will have to spend some time digging around in forums to see what is recommended and available. Don't do much of any tweaking or additions, still running all stock. Might consider changing some things after this major repair gets done. Lord knows I am dropping Moog only suspension and bushing parts into it. Maybe end links will last longer this time around.
 

Realism

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Nov 25, 2015
179
Idaho

mrrsm

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This is what these two items look like in a side by side screen print comparison. I could not find any differences... but the inclusion of this data may just be a generic spec sheet placed there by Hayden. More than likely...the Year differences have something to do with when and how they engage depending on slight variations in engine performance within the Year Ranges. The attached images display the AC-Delco OEM EVCF in case these numbers appear anywhere on the one you ordered. This OEM Fan is meant for a 2002 TB:

upload_2017-3-17_3-50-31.png
 

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Mooseman

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Dec 4, 2011
25,257
Ottawa, ON
Under 2008, if you are getting the tune, get the thermal, less expensive, clutch. For some reason, they were still listing the electro-viscous for some reason.

Had a look on RA's site and the prices have dropped on the more expensive EV clutch since last time I looked. The Hayden 3200 EV is $116 while the thermal Hayden 2851 is $100. Given this small difference now, I would just go with the 3200 if you don't want to mess with the tune.
 

Realism

Original poster
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Nov 25, 2015
179
Idaho
Yeah, price wise it isnt much difference and with the tune and thermal I would only gain about what, 15hp or so? I can put that $99 tune cost to other things.
Still mulling it over another day. Average driver so just not sure how much use I could pull out of a tune.
Planning on doing a bunch of other work so will put my order in Monday or Tuesday. Likely just spring for the 2004 3200 EV.

Not ordered from Rock auto before, are they pretty reliable about products? Anything I should avoid from them?
 

Mooseman

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Dec 4, 2011
25,257
Ottawa, ON
Some will say they're great, others would go postal on them if they had the chance. I haven't had any issues with them. Others had issues with pricing being jacked for no reason. Don't forget to use the 5% rebate code available in the vendors section.
 
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Tiggerr

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Jun 6, 2013
1,324
Perrysburg, OH
Just watch their shipping cost at RA. If you have Amazon Prime I'd use RA for part numbers and plug them into Amazon and check there too. I beat RA price a lot that way. Even check eBay too sometime get free shipping there and do ok...
 

Realism

Original poster
Member
Nov 25, 2015
179
Idaho
Mooseman, I do have one question about the fan clutch. Why is it that failing fan clutch would cause reduced power if it is not locked into full ON position?
I can understand the concept of power needed when it is stuck engaged, but what about in my case where there is no Jet engine roar and it seems more like a lack of full engagement. (assume I should have really felt it tugging harder if it was working properly).
 

Mooseman

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Dec 4, 2011
25,257
Ottawa, ON
The fan clutch shares the same 5V reference as the throttle so it could throw a REP and code for that. Unplug the fan if you are getting REP to eliminate/confirm the fan causing it.
 

Realism

Original poster
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Nov 25, 2015
179
Idaho
Sorry its been a while since my last post on here. Life came up and had to take care of some things here.
Forgive me, but what is a REP code? I assume that is different from a CEL or other code normally found with a scanner.

P.S. -----
So essentially unplug the fan and drive it a bit to see if I the sluggishness is gone, which would point to the fan clutch being the culprit for sure .. ?
 
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Realism

Original poster
Member
Nov 25, 2015
179
Idaho
Had the O2 sensor out earlier to test for clogged CAT, but didn't affect performance So I screwed it back in and ended up D/C neg terminal for 20 minutes to reset (idle was high from having the O2 sensor out), just bout flipped out because when I reconnected nothing came on for the HVAC, no display or anything, D/C neg terminal and reattached and it came back on. Jeez the gremlins these things have.

Decided to go ahead and try disconnected the fan electrical plug and ran it off the 2 miles down the road to auto store to return the O2 sensor socket I rented. The first words out of my mouth were "HOLY B@LLS"! I guess it must have been dying out when I bought it a few years back, man the amount of difference. Went from 0-50 fast whereas 0-50 plugged in felt like a 20 second snail endevour.

When I got to the parts store, I plugged the fan clutch back in and it was running stronger, not as good as it was without it plugged in, but not as bad as what it was doing. Or could just be me trying to trick myself... who knows.

But wow, so based on that is it safe to assume the inevitable
 

Mooseman

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Dec 4, 2011
25,257
Ottawa, ON
REP is Reduced Engine Power. It has its own light and codes.

Sure sounds like your fan may be locking up more than commanded. Would also affect MPG. If you get a new one, go for a Hayden. Best price/quality. Dorman is garbage. ACDelco is overpriced.
 

Realism

Original poster
Member
Nov 25, 2015
179
Idaho
Yeah after the few run ins with Dorman, so not picking them, besides that I think i heard something about having to retrain the PCM with the Dorman model.

You're spot on with the affect MPG. Sluggish accel showed 2mpg avg on DIC, unhooked it went to 6mpg avg on DIC, so looks like I will be getting my 24mpg back yay!

You've still got me thinking on that Tune if I nab the thermal clutch, but I cant see what else I could use the Tune for, so likely stick with the hayden I looked at up above.
Just wonder what I did that must be causing it to lock more than commanded. Hmmm oh well, water pump needs replaced anyways. . .
 

Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
A tune can wake it up a bit but tuning out torque management at the same time. Thermal is less troublesome and will last longer. It's also cheaper so the tune and thermal clutch come to about the same as an electro-viscous clutch. I'd go that way for sure. Lime-swap.com ( @limequat here) does it for $99 shipping included. Definitely worth it if you can go without the truck for a few days while the PCM is out getting tuned.
 

Realism

Original poster
Member
Nov 25, 2015
179
Idaho
Do I need to say what exactly to tune for or is it like an <all-in-one> package just by asking to be tuned.
 

Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
He probably has a list of things but these I would get:
- turn off fan codes
-turn off torque management
- turn off PWM torque converter engagement (this one gets rid of mushy clutch engagement)
- firmer shifts (depends on your preference)
- improved overall performance

He may suggest other stuff but those are the ones I can think of.
 
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Tiggerr

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Jun 6, 2013
1,324
Perrysburg, OH
I think he has a kind of order form on his site... probably best to try and call him or email him though...


I'd have the SAIS codes tuned out too...
 

Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
Oh yeah, forgot about the SAIS.
 

limequat

Member
Dec 8, 2011
520
Do I need to say what exactly to tune for or is it like an <all-in-one> package just by asking to be tuned.
I have a form on the website, but basically this: Make, Model, Year, Gear Ratio, and Tire Size. From there anything specific you want. In your case, disable the fan codes. On top of that I recommend dialing back torque management and firming shifts. 2006+ are more responsive to tunes, but all will benefit from increased throttle response and better overall power.
 

Mooseman

Moderator
Dec 4, 2011
25,257
Ottawa, ON
And don't forget the SAIS :smile:
 

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