New and Need help with 2003 Yukon SLT

[Hype]

I purchased my first 2003 GMC Yukon SLT with 160,000 miles on it from a Private seller. I paid 4500. I am happy with purchase but as I don't know much about cars and I don't wanna get "*****" at the mechanics or dealer. ill see whats fixable by asking questions here.

My 03 Yukon does the following:
Starts rough shaking rpm drop and raise
display check engine oil sometimes at start up also when it starts rough
when I shut my drivers door it says rear door ajar
belt squealing when I start up and when I accelerate
its leaking oil center of engine bay (pic included) spots on drive way from sitting a week.
also I was told while my engine is running no ac on, you hear a constant "tick tick tick"

 

[adventurenali92]

The belt squealing means you probably need to replace the front serpentine belt. The get crack when they get old and start squeeling. Its a cheap part from any of your local auto parts stores.

 

[Hype]

The belt squealing means you probably need to replace the front serpentine belt. The get crack when they get old and start squeeling. Its a cheap part from any of your local auto parts stores.

Thanks will do..

 

[1_8TTony]

My 03 Yukon does the following:
Starts rough shaking rpm drop and raise
display check engine oil sometimes at start up also when it starts rough
when I shut my drivers door it says rear door ajar
belt squealing when I start up and when I accelerate
its leaking oil center of engine bay (pic included) spots on drive way from sitting a week.
also I was told while my engine is running no ac on, you hear a constant "tick tick tick"
View attachment 69404

Let's see....one thing at a time:
Starts rough shaking rpm drop and raise..........gotta know if this occurs on every start up or just on a "cold" start up. Could be coolant level related. Could be a bad coolant temperature sensor. Could be a bad air intake temp sensor. Could be an ambient temperature related problem. Need more info.

display check engine oil sometimes at start up also when it starts rough...........this would be normal with a low engine rpm situation. This is a problem due to the low rpm circumstance, not a primary cause of the event happening. Fix the low rpm situation and the Check Engine Oil situation will go away.

when I shut my drivers door it says rear door ajar..........a rear door switch is probably broken and you will need to remove the interior panels from the doors to find out which switch is busted or misaligned. Easy fix, just time consuming.


belt squealing when I start up and when I accelerate..........I bet it's a broken a/c belt tensioner. I run into this situation atleast twice a month. A customer will bring thier truck in complaining of this same situation, asking the shop to replace the serpentine belt, when this happens, it is always the a/c belt tensioner. A 30 dollar part. A 20 minute repair. The squealing under acceleration is a dead give-away that the problem is with a belt tensioner. Serpentine belts on an LS series engine will snap way before they begin to squeal. There is a 'guage' molded into the body of the SERPENTINE BELT tensioner which gives you an idea of how much the belt has stretched. Take a look at your serpentine belt tensioner guage markings. The a/c belt tensioner has no markings. It is the a/c belt tensioner body that cracks and allows the belt to squeal. These engines have two belts. One 'serpentine' belt and one a/c belt.

its leaking oil center of engine bay (pic included) spots on drive way from sitting a week..........Broken oil pressure sensor. The sensor breaks and oil pours down the engine block and transmission. Once the oil gets down to the bottom of the transmission, it will appear as if the rear main oil seal is leaking. 9 times out of 10, it's the sensors fault. An easy fix for any home mechanic, but can get pricey for a shop to do it. Shop price is right around 500 bucks. The parts are less than 60. (new oil sensor and new intake manifold gaskets).

also I was told while my engine is running no ac on, you hear a constant "tick tick tick".........classic symptoms of worn out lifters. I replace these atleast once a week on customer cars. Figure on at least a fifteen hundred dollar repair for these. Not a difficult job at all. But it is time consuming and requires some specific tools and skilled knowledge of engine assembly. Online parts prices are right under $400

 

[Hype]

Let's see....one thing at a time:
Starts rough shaking rpm drop and raise..........gotta know if this occurs on every start up or just on a "cold" start up. Could be coolant level related. Could be a bad coolant temperature sensor. Could be a bad air intake temp sensor. Could be an ambient temperature related problem. Need more info.

display check engine oil sometimes at start up also when it starts rough...........this would be normal with a low engine rpm situation. This is a problem due to the low rpm circumstance, not a primary cause of the event happening. Fix the low rpm situation and the Check Engine Oil situation will go away.

when I shut my drivers door it says rear door ajar..........a rear door switch is probably broken and you will need to remove the interior panels from the doors to find out which switch is busted or misaligned. Easy fix, just time consuming.


belt squealing when I start up and when I accelerate..........I bet it's a broken a/c belt tensioner. I run into this situation atleast twice a month. A customer will bring thier truck in complaining of this same situation, asking the shop to replace the serpentine belt, when this happens, it is always the a/c belt tensioner. A 30 dollar part. A 20 minute repair. The squealing under acceleration is a dead give-away that the problem is with a belt tensioner. Serpentine belts on an LS series engine will snap way before they begin to squeal. There is a 'guage' molded into the body of the SERPENTINE BELT tensioner which gives you an idea of how much the belt has stretched. Take a look at your serpentine belt tensioner guage markings. The a/c belt tensioner has no markings. It is the a/c belt tensioner body that cracks and allows the belt to squeal. These engines have two belts. One 'serpentine' belt and one a/c belt.

its leaking oil center of engine bay (pic included) spots on drive way from sitting a week..........Broken oil pressure sensor. The sensor breaks and oil pours down the engine block and transmission. Once the oil gets down to the bottom of the transmission, it will appear as if the rear main oil seal is leaking. 9 times out of 10, it's the sensors fault. An easy fix for any home mechanic, but can get pricey for a shop to do it. Shop price is right around 500 bucks. The parts are less than 60. (new oil sensor and new intake manifold gaskets).

also I was told while my engine is running no ac on, you hear a constant "tick tick tick".........classic symptoms of worn out lifters. I replace these atleast once a week on customer cars. Figure on at least a fifteen hundred dollar repair for these. Not a difficult job at all. But it is time consuming and requires some specific tools and skilled knowledge of engine assembly. Online parts prices are right under $400

Its usually on a warm start that it displays Check engine oil on the DIC and the trucks rumbles and shakes a bit and rpm drops and comes back up. that's I all I know...

as for the tick tick tick noise damn that kinda hurts is it a major problem to worry about I spent all my money buying the truck I don't know when ill have that much again extra to fix that.

btw thanks for writing me back I really am not knowledgeable on this stuff I just need my truck running good to get to work and back everyday...

 

[adventurenali92]

@1_8TTony , good advice on the belt tensioner. I forgot that mine did the same thing and that's what the cause was. The bearing inside the tensioner was bad and would sqeak while running and while accelrating. It didn't squeal on startup though. But I replaced the tensioner and the squeal/squeal is gone.