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2004 K1500 Suburban 5.3 LT

Will L.

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You just need to chase faulty new parts on top of the actual problem for an additional 10 hours. Then do it again for an additional 7 hours on a different rig and situation. Then total up near a thousand dollars of not needed parts by the time you figure it all out. Feel free to ask me how I know such things, but I bet you have a good guess. Haha

Put a thermometer in the coolant. Ohm read sensor.
Know what you gauge is telling you for real. Then no more guessing for the remaining years of ownership.

Temp guns are cool (pun intended -because I like puns) But dont think the $150 gun reads as accurate as what a $30 thermocouple sensor reads. In my bagOtricks is being a certified thermographer. Playing with the $150 gun vs the multi thousand dollar ones makes a difference. Those will be as accurate and even better. But the basic units are best used once you know the real temp compared to the gun temp. A good example is companies using multi thousand dollar flir guns that accuratly say 97f means your body temp is really 100.1f Few degrees doesn’t sound like much but the 6% variance allowed in auto tools is difference between someone with a fever that they will die in 1 minute vs die from freezing. And skin is WAY better than metal- so...yeah... use the know and compare method with laser temp guns.
 

treegump

Romans 3:22-24
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Will do. I went ahead and purchased the part before reading your reply @Will L. , because the fact the gauge is moving at all makes me think it's not the gauge. However, I'll ohm read the sensor when I get a chance. I came across what it should be earlier and I think I Pinterest(ed) it. I'll look into purchasing a thermometer also to put into my fluids.

The instructions I saw said to drain the coolant from the bottom hose in order to replace the sensor. I realize it might make a slight mess, but couldn't i just pull the old one out and put the new one in with less headache? I'm sure the coolant needs changed/flushed anyhow, so I don't know why I'm making excuses - just asking.
 

ak diesel driver

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If you wait until it cools off so the antifreeze is not under pressure I have successfully changed a sensor without much coolant loss. Alot depends on how hard it is to get to and whether you can quickly swap.
 

treegump

Romans 3:22-24
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If you wait until it cools off so the antifreeze is not under pressure I have successfully changed a sensor without much coolant loss. Alot depends on how hard it is to get to and whether you can quickly swap.
That's what I'm hoping for. Maybe even undoing the coolant overflow (if there's pressure found there. I haven't checked to find out.).

I figured I could also keep the new one handy so that I can drop the old and insert the new.

If I can pull a cast-iron plug from a 160psi airline and install a valve (by opening the valve), then this should be a breeze. ;-)
 

THEFERMANATOR

FRANKENBURBAN
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There is only 1 coolant temp sensor for the system. The PCM reads the CTS and sends the temp reading out over the j1850. If your scanner is showing 160-225, your temp gauge should be showing 180-210. If it isn't you have a cluster issue.

Is this a flex fuel vehicle? In 04 GM had switched to returnless fuel systems on all but the flex fuel vehicles. The fuel pressure regulator in return style systems were known to fail, dump gas into the intake through the vacuum port, and give a rough restart. I've also had alot of troubles with dribbling fuel injectors in that gen GM's that also gave crappy restarts. I would put a fuel pressure gauge on it and see what it does when you shut it down, and see what it does at key on.
 
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THEFERMANATOR

FRANKENBURBAN
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For ATF, use only dex/merc fluid, not dex vi. Your evap code is probably the evap pump underneath. There was a tsb for them failing because they get plugged up due to mounting location.

As to the deslugger, I've never installed one. I normally used GM's "fix" which was the stretch belt that didn't use a tensioner. Friend of mine put a few in and said they failed just as often, but now you had an electrical device added in that also failed.
 

treegump

Romans 3:22-24
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Evap Pump is different than the A/C compressor, correct? Is there a way to clean the evap pump, or is that a replacement part?

For the recommendation to replace the compressor before it freezes up:
- where do I unplug it to know that it won't kick on?
- Was this a shop replacement? Or is there a way to do it myself, even though I've not done more than topping off the refrigerant?

Not going to lie - considered selling the thing for $3500 and getting something slightly nicer, but fortunately/unfortunately the DMV is closed, haha. My appt to transfer titles isn't until the 30th of May.
 

Will L.

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To unplug the a/c compressor, the wire right on the compressor itself unplugs.
How to know when to replace before it explodes is a wild guess honestly. by that mileage I would just do it asap to be on the safe side.

You would need an a/c vacuum pump and set of gauges to diy it. My current pump and gauges are harbor freight.
The expense of buying them is like paying for the labor of having it done. If everything goes ok, you break even on the first or second time of use. If you don't think you will ever mess with a/c systems again then might be better to just pay a shop.

Basically you PROPERLY AND SAFELY recover the refrigerant in the system according to epa guidelines because doing it the old school at home way of just open a line and let it vent to the atmosphere is illegal by epa rules and you could get in trouble if you get caught, as well as I could get in trouble if I told you to just crack a line and let it vent out. And we all like to keep the epa happy! Remove old compressor, vacuum out the entire system to get out all the oil as well as refrigerant. Then install new compressor, new compressor oil, a/c dye (so if it leaks you can find it), install new high and low side Schrader (connection) valves, then bring the system to as low a vacuum as your vacuum pump will go to and keep it that way for a couple hours ( to get out all the humidity in your humid area.) Then close the gauge valves 1/2 hour to ensure there are no leaks. then add the refrigerant and enjoy the cold air.

Ok someone double check I didn't miss anything or if I didn't explain it right.
I'm guessing there is some descent youtube videos on it.
 

WarWagon

Well it hits on 7 of 8...
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X2 on @THEFERMANATOR advice for bad cluster. Know what's wrong before you throw parts at it. In addition IMO it's more common for a wacky thermostat and bad water pump. We went through several "GM dealer parts" water pumps on our 2002 leaking at the weep hole.

The deslugger never gave me trouble, but, it was the usual AC system failures from 105-121 summer temps. At least it quit the banging from the slugging. Replaced with several AC compressor start stop cycles in rapid fire as this is how it works. It doubled the compressor warranty for me at the time.
 

THEFERMANATOR

FRANKENBURBAN
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Evap Pump is different than the A/C compressor, correct? Is there a way to clean the evap pump, or is that a replacement part?

For the recommendation to replace the compressor before it freezes up:
- where do I unplug it to know that it won't kick on?
- Was this a shop replacement? Or is there a way to do it myself, even though I've not done more than topping off the refrigerant?

Not going to lie - considered selling the thing for $3500 and getting something slightly nicer, but fortunately/unfortunately the DMV is closed, haha. My appt to transfer titles isn't until the 30th of May.
Yes, it is mounted under the rear of the vehicle just in front of the fuel tank. I wouldn't just replace it until you check all the vacuum lines, replace the fuel cap with an OEM(NO aftermarket caps), and post the P code to look up what it is.
 

treegump

Romans 3:22-24
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P code is PO455 - Powertrain

Unplugged the A/C compressor last night before leaving work. Unless my buddy has the equipment and know-how, I'll probably have a shop do it and a coolant flush on it. (I started a deslugger thread under electronics - I think)

Coolant flush only because I already have ~8 gallons waiting for a tox-away day. (Really sucks that there's not a place that takes coolant - if with a charge...).

Waiting until after I get a privacy fence installed ($3k in material - installing myself) - before I start tackling some of these problems. I wonder if I could trade some services above for a Chrysler Concorde, haha.

I've purchased the soldering kit on Amazon to fix the cluster. We'll see how that goes.

Tires seem to grip well but the suspension is nice and bouncy so will probably be looking at shocks and anti-sway bar links in the summer. Considered coil shocks for the added stiffness - but may reconsider that. If I need to stiffen up the ride, I may look into springs. I understand coil shocks are cheaper, but I also understand the argument of putting that much load on shock mounts, haha.
 

treegump

Romans 3:22-24
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That is good to know and makes more sense. It's also interesting to go from the 91 F250 to the suburban - what a sweet ride! However, the cloth seats in the truck do make it a little more comfortable...not much, but a little.

Anyhow, purchased the deslugger, but now from the deslugger thread it sounds like maybe I shouldn't install it?

I had purchased a temp sensor, but if there's only 1 sensor in the system, than I guess I won't worry about installing it since I'm still receiving temperature readings via the OBDII port.

I did receive the cluster repair kit. My hands are shaky, and my wife does woodburning, so I might teach her a new skill. :)

Purchased things for an oil/air filter change and went ahead and purchased a thermostat and fuel filter, as I figured both are good preventative parts.

A few more things I'm noticing
1) it seems when the motor is cold I seem to hear a slight clicking noise, but it only happens at start-up and not always... Or maybe at the initial acceleration? I haven't nailed it down yet.
2) transmission whines - not a lot and not all the time. Again, haven't noticed a pattern.
3) there seems to be some hesitation while driving. Usually only notice it when cruising.
3a) The HHR did the same thing so I would hammer down to try to "clean it out" occasionally, but I also changed out the throttle body, plugs, coils, and O2 sensors. I haven't noticed it since the O2 sensors. Maybe I should try that first even though there's no code?
 

Rockabillyrat

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P0455 is an EVAP large leak code. 3 parts that I replace alot for that are the vent solenoid (referred to as the pump in earlier comments). The sending unit. Gm decided to put a steel sending unit in the trucks. If you live in a northern state they rust out all the time. Requires a tank drop, usually tank straps, sending unit, and lock ring. And the filler neck. With out a smoke machine and flow meters evap codes can be hard to nail down.

But if I had to guess the vent solenoid is where I would start. I've replaced hundreds of those.
 

THEFERMANATOR

FRANKENBURBAN
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If you're doing the cluster, be certain to use only Juken oem replacements. Most ebay kits are china kits and won't last 3 months. I used to do these for local shops. It's not hard to do steppers, but I highly recommend a solder pump to remove the old solder. It takes some practice to get the hang of heating the tab until the solder flows, stand up the tab, and get the solder pump in place to get the solder out before it hardens agains all the while being careful not to overheat it or break the other solder joints. These clusters suffer from broken solders from cold solder joints just like other GM parts.

And the burb uses coil springs. It's not hard to add airbags inside of the coils. Some came stock with load leveling shocks on them.
 

ak diesel driver

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THEFERMANATOR

FRANKENBURBAN
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Not the exact one I have but close, I've used it several times and it works good.
That's basically the same one I use. Some say they use the sponge or wick, but I don't see how they can get all the old solder out with either of those. The pump just works once you get the hang of it.
 
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