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Discussion Starter #41
I meant to say I grabbed the fan and pulled up and down. The bearing in the water pump was shot so there was ALOT of play. I replaced both lastnight. Haven't started it yet though because I lost a bolt.

The alt pulley isn't moving "all over" but when I spin it, it has a very slight wobble. It is also making a quiet popping noise.


How do I test for 5vdc on the T-Body?
 

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Remove the electrical connector from the throttle body and measure between the light blue wire (B terminal) and ground, and the grey wire (G terminal) to ground - Both a 5 VDC reference circuits. I'll attach an image of the connector.

Or, back probe the electrical connector going into the throttle body. Look for the light Blue/black wire going into the connector. Negative lead on your digital multimeter to ground and positive lead of digital multimeter connected to something like a sewing needle with a jumper with 2 alligator clips. Also the grey wire is another 5 VDC reverence voltage. Pierce the blue/black wire insulation and the grey wire insulation with the needle and see if you have 5 VDC when you put the key in the Key On Engine Off position.

Throttle Body Connector.gif


OK on replacing both the water pump and the fan clutch.

Regarding the alternator pulley having a slight wobble and a "quiet" popping I would be inclined to replace the alternator while you are fixing things. One of the bearings in your alternator is likely on it's way out. When I replaced my water pump and fan clutch, I also wound up replacing the alternator because when I turned the pulley, it felt like it had gravel in the bearing. I went ahead an purchased a New AutoZone Duralast Gold alternator because it was manufactured by Remy, and it came with a lifetime warranty. New alternator has been smooth as silk when I spin the pulley by hand.
 

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FWIW...

Typically, a battery is being charged by the alternator to about 13.2V as the engine is running. It's not unusual to see a battery being pushed that hard, as it provides a buffer capacity for a sudden high-amp consumption.

Immediately after the engine is shut off, and there aren't any vampire voltage suckers still taking power to run until they go to sleep, the battery should slowly drop to about 12.7V as it too goes to sleep.

Remember that some vehicles take up to 30 minutes to shut down... for what reason I do not currently know. When you turn off the key, the battery still gets nursed off of by components that need to run for a little longer.

Chemically - the specific gravity of a charged battery will be at 1.265* at 80°F. Here's a chart for you to see what a fully charged battery should look like both chemically and electrically ---- ↓

55526


Dynamically - the specific gravity is the best test of the individual cells - if you can access them below the still-caps that return the vapors that are created inside the battery, back into the battery where they belong.

So - keeping in mind that temperature and charging rate and ultimate draw on a battery will set up differing values - be aware that these numbers are for a battery at approximately 80°F and no draw and having been charged UP TO 13.2VDC by the alternator until the key is turned off and all draws are then nonexistent.

FUN FACT #1 ---> a modern, NO-Service (sealed) "12 volt" automotive/car battery that gets to below 10.6 Volts and is EITHER recharged by the alternator OR a battery charger ------ cannot be trusted any more. It might last another 5-6 months or 10 minutes., It will NOT give any warning - it'll just be DEAD sometime when you turn the key to START.

FUN FACT #2 -----> Alternators do NOT like to charge a low or dead batteries. Alternators only like to work with batteries that are in better condition - usually above 12.4V and a 'bad battery' can actually make the alternator destroy itself or cause it to fail earlier than it might normally do so.
 

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Discussion Starter #44
After changing the fan clutch and water pump the very rough idle sort of lessened but still there.

I am also now getting a loud humming noise in the front end that gets louder as I accelerate. The noise comes and goes but it didn't do that before. It sounds just like an 18 wheeler when it is accelerating. Did I receive a bad clutch or did I ruin it?

I u noticed last night I get a big V drop when I roll my rear windows up/down. Haven't checked inside the door yet. Is a short in a switch for my windows a common issue?

Also, could it possibly be my cam sensor? I figured if it was, it would give me a code and I didn't get any. VVT solenoid is new also. Lmk what you guys think. Thx!
 

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Check your alternator's bearing. When mine started going south, it became quite noisy. I checked it by removing the serpentine belt and moving the pulley with my hand. It felt like there was gravel in it. Engine was much quieter after installing the new alternator.

Also, the newer fan clutches do make a great deal of noise (some describe it as sounding like a jet engine) when the engine is first started and during the first several minutes of operation. That is normal. However, still check your alternator.

Regarding the "...big V drop..." when you roll your rear windows down, a couple of things. One, check the the body ground from the battery. Follow the small black wire from the negative battery terminal to the body/frame and remove the bolt, then clean the area and the wiring terminal so both are clean and shiny. Then reinstall the wire and the bolt. Two, make sure the battery terminal to battery connections are clean and shiny. Three, make sure your battery terminal bolts are tight - not gorilla tight, but human tight. If you have a battery that's more then a couple of years old, get it tested to make sure it has not developed a bad cell - a load test is preferred over a conductivity test, but if you can only get a conductivity test, OK.

No need to replace the camshaft position sensor unless it throws a code.

If you had a window switch shorting out, it would blow a fuse or pop a circuit breaker. If after you have checked the battery out and the grounds out, if the rear windows still cause a large voltage drop when operated, then consider replacing the window regulator and motor assembly. I do know that when they get old and "worn out", they slow down and can pull a heck of a lot of current. I've had to replace all of them in both our 99 Buick Century and 99 Silverado in the last year or so. Made a big difference!
 

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After you get everything running as "normal" as you can, then we can move onto tracking down the causes of the "rough idle".
 

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Discussion Starter #47
I pulled a code C0055 it says rear wheel vehicle speed sensor-short to ground but there are 2 sped sensors on the back end of the T-case. I feel like I'm so close n just hitting a wall here. Anyone have clue?


BTW I gave this code to an oreillys guy and he said it's a code for the steering wheel position sensor. SMH what a ding dong
 

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Is the C0055 a current or a historical code? It does make a difference.

A C0055 says that there is a rear wheel speed sensor circuit malfunction. You'll need to get a schematic of the circuit and find out if the circuit is shorting out, if there is an open (or broken) wire, if there is an intermittent electrical connection, or perhaps a bad sensor. In addition to a schematic, you'll also need a decent digital multimeter (DMM).
 

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Discussion Starter #49
The code does not say pending but as far as old or new I'm really not sure. I've had this RS2 code reader for about 4 months and that day was the first time I scanned the ABS system. I figured it would scan everything at once. I googled symptoms of a bad VSS and I have just about all em. The only symptom I do not have is the MIL light on.


Do you know where or what website I can find a diaghram for the that circuit only, minus all the other irrelevant stuff.

Also, can I diag a bad vss with ohms test of the vehicle?

Thx a mill buddy
 

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For a circuit schematic, join the GMTNation forum, and then you can download from this page:


I am not sure if you can diagnose a bad VSS for the rear wheels with just an ohms test. I know one can check the vehicle speed sensors for the front wheels using a digital multimeter and seeing if the resistance is low AND if it develops an AC voltage (around 0.5 VAC) when the wheel is spinning
 

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That I cannot answer.
 

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I have no idea. Perhaps one of the other forum members can answer that question.
 
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