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Discussion Starter · #1 ·
My car started screeching when slowing down or speeding up from stopped. It would go away around 15 mph and would get louder if I was turning while accelerating or decelerating.

I drove to Tucson from Durango, CO, and the sound slowly got worse, louder, more consistent. I took it to a shop and they said it was the idler pulley, tensioner, and serpentine belt. They replaced all parts.

I drove to Chattanooga Tennessee from Tucson and along the way the sound came back, then got worse and more consistent. I took it to a shop again and they said the serpentine belt needs to be replaced.

Earlier this year, I had the power steering pump and hydroboost brake system replaced, then it suddenly went out on the highway so I had those parts replaced again.

Is anyone familiar with this issue and could suggest other parts to look into?

2002 AWD GMC Safari
 

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Idler pulleys do tend to go on 4.3s. I think i've replaced one on every one I've owned.
The chronology is a bit confusing here.
Earlier this year, I had the power steering pump and hydroboost brake system replaced, then it suddenly went out on the highway so I had those parts replaced again.
When did this happen in relation to the other events? Also, what "it" suddenly went out?
Any pully giving excess drag can cause a belt to wear prematurely. There are different reasons for different pulleys to be able to cause this.
 

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2003 Safari AWD
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The power steering pulley can be pushed on to far or too little. Causing it to not line up with the other pulleys. Probably worth checking it they just pressed it in until it stopped.
Agreeing with this. There is no room for error regarding where that pully must be positioned for the belt to sit properly.
 

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Discussion Starter · #7 ·
Hey everyone - thanks for the tips here, sounds like I need to get the pulley alignment checked. Since I had the belt replaced again, I now smell burning rubber after driving the car, even short distances, and occasionally i've heard other mysterious noises that sound like something is off/loose.

Unfortunately, I don't have many tools or wherewithall to go at it myself. If anyone has a good instructional video or diagram to pass along, I would super appreciate that.
 

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Discussion Starter · #8 ·
Idler pulleys do tend to go on 4.3s. I think i've replaced one on every one I've owned.
The chronology is a bit confusing here.

When did this happen in relation to the other events? Also, what "it" suddenly went out?
Any pully giving excess drag can cause a belt to wear prematurely. There are different reasons for different pulleys to be able to cause this.
Okay, I've written it out below to the best of my memory/ability to describe. Of note - I live in this vehicle and travel for work/play, hence why so many different mechanics and me spinning around trying to figure this all out...

Order of events:
Early May - driving over mountain passes I noticed that the engine was sounding a lot louder, like it was trying hard to accelerate and turn when driving from Durango to Denver.
Late May - I started to think the power steering was going out, it was hard to turn the wheel and made excess noise when pulling in/out of a parking spot. A friend borrowed the car in Denver and added a generic power steering fluid (without asking me first) and when I returned to the car it was worse. I drove back to homebase in Durango and took it to two mechanics: the first said it was the power steering, second said it was the hydroboost brake system and power steering. I had both replaced. They said there was a potential mixing of fluids in the system, but couldn't say what it was.
July - About two months later driving on the highway during rush hour in the rain in downtown Denver, the car completely seized up. I could barely turn the wheel and it would not accelerate. I inched it off the highway and into a parking lot. Got it towed to a mechanic who said the power steering and hydroboost brake system were bad, had both replaced again under warranty. He said the power steering pump did not look like it was new and suspected it wasn't actually replaced or replaced with an old part.
August - Belt was squealing like crazy when I finally got it back so I took it to a different mechanic who was a trusted place of a friend in town. They said I needed to replace the belt and pulley (I don't recall which). Did both. Car ran great for a few months then...
December - Belt squealing again, took to a mechanic in Tucson who said I needed to replace the idler pulley and belt. Replaced both, and left to head back to Tennessee. After a few hundred miles, the belt began squeeling again. Once I made it to Chattanooga (1700 miles away), I took it to a mechanci who said the belt was bad, likely a cheap part, and replaced it
Now - Belt smells like burning rubber when I'm driving and hearing noises in the front end. Saga. Continues!
 

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Since you have replaced the belt, idler pulley and power steering components with little success, you probably have an a/c compressor, alternator, water pump or power steering/brake pump dragging, Even a "cheap" belt should not perform that poorly so soon.

Does the sound and burning smell go away if you turn the a/c off? If yes, then you have found the problem. Either the clutch bearings are failing or the actual compressor is failing. Is the alternator charging properly? Hard starting, dim lights, voltage gauge reading low? Alternator bearings could be failing. Is the temp gauge always where it should be? No overheating under load? Water pump then. Usually the bearings start to fail and the fan wobbles while running but don't cause belt to burn - it usually flies off the pulley.

The only other choice would be the power steering/brake system. The power steering pump has a pressure regulating valve in it and unless it's clogged, very low on fluid or filled with improper fluid (ie brake fluid or a high viscosity oil) for an extended period of time, not the problem.

There are only so many possibilities for the problem you have described and you have already repaired half of them. In our experience, if not the old belt, idler pulley or alternator, 9 out of 10 times it's the a/c compressor.
 

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If you're smelling burning rubber from the belt you're not far from becoming a pedestrian :eek: If everything else checks out OK, look at the spring-loaded idler arm. It should move freely with no looseness, and I've seen a couple on other vehicles get bent when some idiot pried on them. Kind of rare but does happen.
 

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My only slightly educated guess in this would be the pressure regulator in the power steering pump initially went. The power steering pump supplies the power boost to the brake system. The adding of a potentially wrong fluid could have caused further damage.
I don't know if the fluids mix or not, and what the effects really would be if they did, but it seems to have caused your brakes to engage whether or not you were on them. When the parts were replaced, were the fluids flushed and replaced with what they should have in those systems? They could possibly still be affected if not.
There is also the possiblitly of any of these other parts' pulleys going as well, but they can be tested for true, resistance and freeplay without replacing. Really the tests just involves removing the serpentine belt. For resistance, spin each pully. They should turn freely by hand, except the crank, and I'm not sure, but you may have to disconnect the output to the power steering pump and reroute directly back to the reservoir. Otherwise, there may be some light resistance in the alternator, water pump, and an unengaged AC compressor, but they should be able to move by hand. They also should not squeak at that low speed at all.
For freeplay testing, grip opposite sides of each pulley, they should not be able to shift or wobble if you try to shake them.
For true, if you look down at them, with a point of reference such as a straight edge or plumb bob, while spinning them, they should not vary out of plumb. |/|\|/|\
 

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Also you said after someone added generic fluid it was much worse. If someone inadvertently used brake fluid (similar style bottles) in the power steering assembly it causes the rubber o-rings and seals throughout the system to swell and not work the way they were intended to - especially the pressure regulating valve and hydro-boost unit. That will cause excessive pressure in the system, pump drag, belt slippage, poor braking and steering performance.

We have seen this happen in other vehicles. You said the hydro-boost and power steering were replaced (assuming you mean steering box), so they are probably not the cause, unless they left contaminated fluid in the system.

You stated it appears the pump was not replaced. Chances are good the pump is now junk. Rule out the a/c compressor first (it's much easier to get to). Turn off the a/c and see if the problem goes away. If not, the power steering pump is done for.
 

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If you drove it a thousand miles,or so, your belt probably was not "squealing", but squeaking.
Haven't seen anything about replacing the tensioner. Anyway, some common things--
Pulley alignment.
Idler and tensioner bearings.
Alternator bearings, but, when they go, they go, if ignored, you end up with a locked up alternator.
Tensioner, they can get weak, not have enough tension, or they can partially seize, causing too much tension, and not enough movement.
A/C clutch bearing. They can go bad, and run for a long time. It's amazing how many people replace a belt, and never think to turn off the shop radio, and spin the A/C pulley, with belt off, or to spin it while touching the compressor, you can feel if it is dying.
 

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PS pulleys can be put on wrong.. this would cause misalignment.
I've checked them in the past with a log straight edge.

Bad pulleys can cause issues too.

You'll have to pull the shroud to see if things are in alignment.
You'll have to pull (or loosen) belt to spin pulleys looking for issues.

This shouldn't be too complicated.

PS: Avoid "belt dressing"... my experience is that it makes things worse.
Any contaminates (oil or antifreeze) on belt must be cleaned off.. same for pulleys.
 

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Discussion Starter · #15 ·
thank you all so much for your comments here, they have been extremely helpful as I’ve poked around and trouble shooted with the mechanic here in Chattanooga.

It looks like the power steering pump was not seated when it was installed. They said there were threads showing. They told me that they tightened and realigned the power steering pulley and flushed the system and replaced the fluids.

I drove about fifteen minutes from the shop, parked the car, messed around organizing my camper in the back for about a half hour, then noticed a puddle under the frontend. I got underneath and there were multiple steady drips coming from the middle of the engine cabinet. It looked like they were concentrated around a couple of lines there. It was slick oily clear fluid. I had a doctors appt so the car sat there about an hour then I drove it back to the shop. This afternoon they let me know that the water pump was leaking coolant, likely a seal.

any thoughts?
 

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Discussion Starter · #17 ·
Water pumps go bad. If leaks, would be same color as your coolant, which could be green, reddish,orange/pink, or almost clear if a universal fluid.
Thanks MechBob for the pointers on the fluid. It was a mostly clear fluid, and I really can't recall what color I put in there when I last topped it off. As to your other points - I did have the tensioner & idler pulleys replaced earlier this year, not sure about the alternator bearings. Thank you for the list above as I'm sure it will be helpful as I work through this further.

I am curious if realigning the pulleys could have caused the damage to the water pump. Again, there was no visible leakage of the pump before I took it to the shop because of the burning rubber smell and the occasional rattling noise while accelerating. It was there for several days and they said they couldn't find any issue, at which point I asked them to look at the pulley alignment based on feedback from this thread. I am having a hard time trusting this shop a) terrible reviews on google, including them ripping people off, poor customer service, and claiming they did work they didn't do on multiple occasions when people took their cars for a second review. I really don't trust what they're telling me (to be honest, these have treated me extremely poorly and I do not say that unless it is warranted.)

So...I'm back here, asking you all who have always been so helpful since I bought this vehicle. A friend in town who is a mechanic has agreed he is willing to help me out and let me work alongside him so I can learn some more as well. I'm curious fi there are other things I should be looking for or if there is a chance that something was done while it was in the shop that could have caused the water pump to fail.
 

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Discussion Starter · #18 ·
Also you said after someone added generic fluid it was much worse. If someone inadvertently used brake fluid (similar style bottles) in the power steering assembly it causes the rubber o-rings and seals throughout the system to swell and not work the way they were intended to - especially the pressure regulating valve and hydro-boost unit. That will cause excessive pressure in the system, pump drag, belt slippage, poor braking and steering performance.

We have seen this happen in other vehicles. You said the hydro-boost and power steering were replaced (assuming you mean steering box), so they are probably not the cause, unless they left contaminated fluid in the system.

You stated it appears the pump was not replaced. Chances are good the pump is now junk. Rule out the a/c compressor first (it's much easier to get to). Turn off the a/c and see if the problem goes away. If not, the power steering pump is done for.
Thank you for your thoughtful reply here. I did rule out the a/c as the smell still occured with it turned off.

Took it to the mechanic (re: my most recent posts). said that there was mixed fluid in the power steering system, so they flushed it and realigned the power steering pulley (said it wasn't screwed on all the way, with a few threads still showing). I drove away, parked, and it was leaking tons of oil - brought it back, they looked at it and said it was definitely coolant and the water pump was bad. Do you think these could be connected at all? and is it worth re-inspecting the power steering pump?
 

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I'm not going to say it is impossible, but not likely, unless they actually did something to it other than put the belt back on. Running with the belt mis-aligned for a long enough time could have put strain on the bearing that could allow it to leak, but how mis-aligned and for how long? I don't think there have been studies on that.
If you have someone with you that may know what they are doing, sure by all means check everything they are comfortable with. A local friend has more invested in you than a local shop. If that friend just so happens to be a mechanic, well!
 

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Now there're two different problems. You said it was leaking tons of oil after being repaired again. When you took it back they said the water pump was bad? What was actually leaking?

I have had Astro vans with over 200k on them with the original water pumps on them with no leaks. Not very likely to me anyway that a slightly misaligned power steering pump pulley would cause the water pump to leak. Just seems a little far fetched to me.

It's easy to differentiate between power steering fluid and antifreeze. If it was actually oil, then it was definitely not the water pump. Antifreeze will wash off your hands with water while power steering fluid won't (well unless you add soap).
 
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