swingandmiss
TYF Newbie
- Joined
- Aug 14, 2017
- Posts
- 15
- Reaction score
- 1
First time post. I've been working with our mechanic to chase down an issue with our 2012 Yukon Denali XL. 120,000 miles. Very well cared for truck.
First problem - I was intermittently getting a "service battery charging system" warning. However, the battery light did not go on. I noticed the voltage did vary quite a bit, maybe in the 12-15 range. Never did the battery light come on. Brought it in and my mechanic found the voltage generated was low. Changed the alternator.
This did not solve the problem because two more times got the "service battery charging system" and "service electrical system" warnings. Never did I have any problems turning the truck on. Turned over instantly every time.
Second problem - Turned the truck on one day and got an odd sound immediately. To me, it sounded like a bearing going. And then it went away after idling for a couple minutes. Backed out of the driveway, gave it some gas and the truck started shuttering. The "stabilitrak off" and "traction control off" warnings came on, then "service electrical system" warning. All warnings lasted about 3-4 seconds and then back to normal. Truck had little power and felt/sounded like it was misfiring. The dash also blinked off and then back on. Towed the truck in to the shop. 4 or 5 error codes, non related per my mechanic. Figured it had to be the computer as it's the only thing that connects to all the systems. Replaced the computer and programmed.
Over the next 24 hours, the truck turned off once at a stop light and then got another "service electrical system" when idling. Voltage remained at 14.5 during the warning. No other lights.
Third problem - Brought it back to the mechanic and they found a lose cable to the alternator. Said they could wiggle the cable and the low voltage warning would pop up every time. Replaced cable.
Fourth problem - The very next day, after a day of driving perfectly, driving onto the freeway onramp got the "traction control off" and "stabilitrack off" warnings at the same time the truck started misfiring. Warnings stayed on for 3-4 seconds. This time the check engine light was on and then back off, even before the other two went away. No power, even though the engine seemed to be revving fine. Close to the shop, so drove it back carefully. The engine knocking sound was back the entire time. I also had another rattle that sounded like what a loose exhaust would sound like. Metal banging on metal. But only once I hit 1500rpm. Under 1500 and it generally didn't make the sound. Not completely consistent though. Dash went blank for about 10-15 seconds on the way over. Got to the shop and had them check the codes without turning off. The knocking sound was there, but the metal on metal one was not. We couldn't get that one to come back. But it was down on power and not driving well. Center console also flashed blank for a second.
After 4 days of diagnosing, they say it's something in the engine. The sound is coming from the bottom end. Maybe a stuck lifter. They say the oil smells burned and they just changed it the week before. Also, long history of cylinder 6 misfires. Says needs a new engine. I keep thinking that there is something related between all the problems. They are saying all individual problems. I'm having a real hard time believing this is the case due to the timing. I am ok replacing the engine if it needs to be replaced. But I don't want to replace the engine if something is the problem, or if something else caused the problem. I am hoping the wisdom of the internet can help.
First problem - I was intermittently getting a "service battery charging system" warning. However, the battery light did not go on. I noticed the voltage did vary quite a bit, maybe in the 12-15 range. Never did the battery light come on. Brought it in and my mechanic found the voltage generated was low. Changed the alternator.
This did not solve the problem because two more times got the "service battery charging system" and "service electrical system" warnings. Never did I have any problems turning the truck on. Turned over instantly every time.
Second problem - Turned the truck on one day and got an odd sound immediately. To me, it sounded like a bearing going. And then it went away after idling for a couple minutes. Backed out of the driveway, gave it some gas and the truck started shuttering. The "stabilitrak off" and "traction control off" warnings came on, then "service electrical system" warning. All warnings lasted about 3-4 seconds and then back to normal. Truck had little power and felt/sounded like it was misfiring. The dash also blinked off and then back on. Towed the truck in to the shop. 4 or 5 error codes, non related per my mechanic. Figured it had to be the computer as it's the only thing that connects to all the systems. Replaced the computer and programmed.
Over the next 24 hours, the truck turned off once at a stop light and then got another "service electrical system" when idling. Voltage remained at 14.5 during the warning. No other lights.
Third problem - Brought it back to the mechanic and they found a lose cable to the alternator. Said they could wiggle the cable and the low voltage warning would pop up every time. Replaced cable.
Fourth problem - The very next day, after a day of driving perfectly, driving onto the freeway onramp got the "traction control off" and "stabilitrack off" warnings at the same time the truck started misfiring. Warnings stayed on for 3-4 seconds. This time the check engine light was on and then back off, even before the other two went away. No power, even though the engine seemed to be revving fine. Close to the shop, so drove it back carefully. The engine knocking sound was back the entire time. I also had another rattle that sounded like what a loose exhaust would sound like. Metal banging on metal. But only once I hit 1500rpm. Under 1500 and it generally didn't make the sound. Not completely consistent though. Dash went blank for about 10-15 seconds on the way over. Got to the shop and had them check the codes without turning off. The knocking sound was there, but the metal on metal one was not. We couldn't get that one to come back. But it was down on power and not driving well. Center console also flashed blank for a second.
After 4 days of diagnosing, they say it's something in the engine. The sound is coming from the bottom end. Maybe a stuck lifter. They say the oil smells burned and they just changed it the week before. Also, long history of cylinder 6 misfires. Says needs a new engine. I keep thinking that there is something related between all the problems. They are saying all individual problems. I'm having a real hard time believing this is the case due to the timing. I am ok replacing the engine if it needs to be replaced. But I don't want to replace the engine if something is the problem, or if something else caused the problem. I am hoping the wisdom of the internet can help.
