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Discussion Starter #1 (Edited)
Did the mechanical fan delete over the weekend and removed air pump and all components, installed primary fan. Filled up with water just to do leak test. Primary fan will not come on, disconnected sensor on water pump, secondary fan on no primary. switched relays checked 40 Amp fuses checked all connections, still secondary fan. removed primary fan wired direct to battery fan works GR8. Only thing I did not check is green wire going to PCM, if that wasn't making contact in that pin would that affect it? I'm stumped, HELP:crying: Glad I have other vehicles to drive

The original plug to secondary fan motor is now obsolete correct?
 

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It has been 16 years since I did mine.
My 95 Chev, I am 98% sure I had to add the primary trigger wire ( green) to "A 11" .
Did you ?

If the wiring is all there, you should be able to pull PCM A and ground 11 to make fan go on.

If you did not run that wire or there is something wrong between PCM and underhood fuse box, you could "steal" the old air pump trigger wire .

Take the brown out of A14 and move to A11 ,

Remove it from air pump relay connector and move to primary fan relay connector.

All the above ASSuming this is your problem.
 

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Discussion Starter #3 (Edited)
I installed the green wire to the PCM red connector to connector location 11, per Innovative wiring instructions, please explain in detail how I would wire from air pump harness? Thanks for response 95 Wagon, Is PCM red connector same as A pcm connector as you refer to?

Beautiful wagon you have, is that a DGGM?
 

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I have never seen Gary's instructions but have heard nothing but good about the guy , so likely you have made some silly mistake like looking at a connector in the wrong orientation.

If you have run a new green wie to A11 , the air pump stuff I mentioned is not required.
It is just (in my opinion) an easy way to gain fan control without having to string a new wire from one corner of the engine compartment to the other .
See picture, yes "A" is the red one :)

Maybe start by backtracking a bit.

The fan motor is grounded, yes?

At the relay plug,
( take these numbers with a grain as I am nowhere near my books or car)

ignition off , you should have power at the terminal 30 ( big red I think)
ignition on , you should also have power at 85 ( lt blue )could be 86
85 and 86 are the relay windings . in a resistor suppressed (no diode) relay, the two can be wired either way.
If you put power to one and ground the other, the relay will click on.
The big "working" power going in 30 and out 87

At any time , at the relay socket , you should be able to jump 30 to 87 ( the two big wires ) and the fan should run, does it?
THE NEXT LINE IT IS CRITICAL YOU HAVE THE CORRECT TERMINALS WHEN TESTING_GROUNDING

If you have PCM plugs all disconnected, turn they ignition on.
On the red plug you will be able to ground A10 and the secondary fan will run
On the red plug you SHOULD be able to ground A11 and the PRIMARY fan should run.
IF when it doesn't, can you at least hear the primary relay click.

What we are trying to do is determine , is this issue with ,
PCM is not controlling relay
Relay is not being turned on,
Relay is not powering fan.
Fan ground issue

My car is Medium Adriatic Blue over gray

The two tone was not terribly common, wasn't my first choice but has grown on me over the years
Thanks
 

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Discussion Starter #5
OK, Finally determined it was a ground issue with the primary fan even though both grounded on same lug, cleaned real well with sandpaper reinstalled, thinking I might go with the air pump trigger and switch on PCM and fuse box like you mentioned so don't have that one wire going to opposite side of Engine compartment. Thanks 95 Wagon, Since I'm still in Cooling section have one more question, I'm running a 160 T-Stat, before I flush again and do antifreeze should I put 180 T-stat back in? I'm in South East Florida, I have read lots of conflicting stories on this subject. Thanks again
 

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thermostat , ask 10 people, get 11 opinions.

I ran a 160 in mine when it was an LT1 but was the engine was not stock.

Biggest deal is the fan settings,
If you run a cold stat with stock fan settings you end with ridiculous temperature swings .

Now you have only electric fans , it will be even worse.

Cool day on the highway I would guess you will see 170 ish or less, in traffic with no AC on you will be up in the high 220s.

So the 180-160 argument is not as (IMO) nearly as important as addressing the fan turn on temps.

Is yours stock now? Do you have the ability to read the PCM and make changes?

I typically have the secondary fan come on only a couple degrees higher than the primary.
My thinking is you set the primary to where you want to try and hold temp.
If the primary is loosing the battle, why wait another 5-10 degrees to ask the secondary to help ?

Too aggressive settings , of coarse, and the fans will be on all the time.
 

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Discussion Starter #7
My car is completely stock other than air pump delete, mechanical fan delete, and home base delete. Again conflicting stories on lowering fan start temps. One member on here "Grandpas Wagon" has had a wealth of information. If your car was well maintained, with normal scheduled Maint. you should be able to do a Mechanical fan delete with out any PCM changes. I'm the second owner of this car, the file that came with this car is four inches thick. Previous owner had a bug stuck in the rear third brake light and took it to the Buick Dealership. That being said, My car has been meticulously maintained by first owner and myself also. I do not have any ability to lower Fan start temps or know where to even begin. All being said and done temporarily would you leave the 160 or put the 180 and go from there. When I had the mechanical fan I could leave car running in driveway for a hour with A/C on and gauge would never even come close to half way mark. (with the 160)
 

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A/C on skews things because it forces on fan on.

If your V08 car sat idling there was fan wash all the time and as the bimetalic spring felt more heat the rad air increased, the fan would pull harder.
The mech fan cars were very good at maintaining the temp around the stat temp or a little above.

NOW your car ( when the AC is off) will sit with no airflow at all through the rad or across the engine until it gets to 225 degrees!
And if it is a hot day and the primary can't quite handle it , the temp will continue to rise until 231 degrees before the secondary fan tries the haul it down.

Get ready to see large gauge swings :)

Yes the stock system , well maintained is OK with stock settings,,,,,,,,,

That said, read up on all the guys complaining about rock hard brittle wiring harnesses , broken heater flow valves, "t" s ,

Yeah, running an engine at 225-230 is efficient , and with pressure and coolant you can get away with 240-250 but I choose not to .
I feel much better trying to keep around 195-200.

If you are or have been convinced that there is nothing wrong with the stock fan settings, then don't bother with a 160 stat because most of the time you are going to be well above that anyway.

All just my opinion, now let's get ready for all the others ,,,,,,,,,,,,,,,,,,
 

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When you swapped the mech primary fan for the electrical primary fan, did you update the pcm file to let it know that it now has 2 electrical fans?
It's a simple switch that needs to be toggled.
 

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Discussion Starter #10
I was told by many on the forum nothing to do on PCM on a 95 LT-1, other than lower fan start temps if you choose to do so.
 

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When you swapped the mech primary fan for the electrical primary fan, did you update the pcm file to let it know that it now has 2 electrical fans?
It's a simple switch that needs to be toggled.
If he used the Innovative Wiring kit, nothing needs to be done to the PCM.
 

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The switch in the calibration is for fan diagnostics.

When enabled, the PCM looks for current in the fan trigger wire circuit.
If it sees none , from either ,

Broken wire,
missing or dead relay
blown- missing 10 amp relay fuse.

it will set a code.

Not turning the primary fan switch in the cal will do nothing to fan operation , only not show a code if there is a failure in the primary fan low current circuit.

Comes down to , NO you don't have to but if you have access to the calibration why wouldn't you .


Now It should be noted that if you use the AIR pump wiring to run the primary fan like I suggested, you need to turn off the AIR pump diagnostic code.

I should have said something before , but ASSumed pretty much everyone is inside their PCMs now days
 

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Discussion Starter #13
Okay while I wait for my new Factory GM tee and and Dayco #88371 coolant tank to tee hose from FEEBAY for less than $20.00 for both, I know doesn't match my greenie hoses, can't see it anyway under tank and did not want to deal with cutting that compression fitting off. Probably going to get yelled at but while Im waiting looking for the best affordable front rotors and pads. Also anyone know of any kind of Kit out there for for our cars for rubber lined band/worm clamps.. Thanks Guys I hear these stories of members with 250 plus miles, I have 135, Shes in GR8 shape, My Golden Retrievers love her, and she is not my Daily driver. Had the tranny rebuilt in 2015 with a Corvette Servo (am I saying that right) for $1800, I blow these kids away at redlights with loud obnoxious riceburners. Jump in Grandpa, love your insight.
 

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Discussion Starter #14
OK quick recap, car overheated on New Years eve on my brother in law,(heater restrict-or blew) had a set of Greenie hoses in my Garage since 2011, did a complete flush including knock sensors. Did the complete Mechanical fan delete with Gary's kit, had some problems with that with fans coming on, figured that out with 95wagons help. Also did air pump delete removing all tubing that snaked up and over to passenger side. So the tee popped a pin hole on it on my greenie hose so I purchased a new GM Tee and tank to tee hose versus cutting off that banding clamp. Installed that yesterday did my antifreeze, bled the air, ran the, heat ran the A/C, perfect temps never went over 12:00 on temp gauge. Went out this morning let it run twenty minutes with heat on, temp never came close to 12:00 o'clock. Noticed heat wasn't very hot. Primary fan running, secondary fan cycling kicking on and running for a couple minutes and shutting off. I feel heater hoses inlet HOT, return lukewarm but still good flow. Didn't think much of it as we might need heat two days here all year (except for this year, Global warming my ass). Went back out checked all my joints for leaks noticed restrict or was wet on bottom, went to tighten with 5/16 nut runner and restrict-or nipple broke off and fell apart. Is this a kw-inky dink or they were bad from sitting and old. Thinking of bypassing, good or bad, Auto Zone has $5.00 rebate on Anti-freeze, that's a good thing. Did get to drive it, with all the mods you think you have a new fast car like when you have a fresh all change. He he
 

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Having the same issue with my B4U which had the mech fan. Put in a temp bypass switch for summer temps. Need to order gary's kit including a bypass switch for the track.
 

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Buddy parting out a B4U with dual fans using Gary's kit. Main fan harnesses intact,and in excellent condition. Disconnected from fans,ground so far. Perhaps an older kit,or circuit breakers on a bracket were added. Saw Gary's kit pictured,and am planning to remove this for my friend to sell as carefully as I can.
 
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