Hopefully the mechanic is good at diagnosing running problems. Let us know how things turn out with the car.
:welcome:
:welcome:
3.6L LLT RPM jumping, engine surging, poor gas milage
I’ve seen posts similar to this issue I’m experiencing but wanted to throw out my experience. It started with noticing my car feeling like it was jumping slightly while in cruise or sometimes when I’m pressing the Accelerator. I recently noticed my RPM bouncing up and down very noticeable when in cruise or any other time really. Gas Mileage is horrible now as well. Got the oil changed and put fuel injector cleaner and it seemed to act better but soon (a few days of driving) symptoms returned.
Took it to a state park with many steep hills with a speed limit of 15 and at two points when going up the steepest it felt like it was going to choke out and die but I gassed it and it went away. I drive it daily in home health and noticed it getting worse with the engine jerking a couple of days ago it felt like I was driving on a cobblestone road when trying to accelerate onto the highway but after pressing gas harder it stopped. took it to the mechanic not throwing any codes.
Took it to a state park with many steep hills with a speed limit of 15 and at two points when going up the steepest it felt like it was going to choke out and die but I gassed it and it went away. I drive it daily in home health and noticed it getting worse with the engine jerking a couple of days ago it felt like I was driving on a cobblestone road when trying to accelerate onto the highway but after pressing gas harder it stopped. took it to the mechanic not throwing any codes.
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Girl friend has same vehicle you do and same thing was happening. Hers had 147k miles so I changed spark plugs so far its running better one problem I notice was Oil inside the spark plug tubes which could be from manifold or a bad head gasket. But here are somethings that can cause it... Spark plugs, Coils (normally you will see rpm issues more often if its coil issue), fuel filter, Head gasket, transmission issue ie slipping. The engine is 3.6 V 6 acadia AWD.
Did you ever find out what was wrong with your car
Hello, I have also started feeling very similar symptoms to this, surging, bouncing RPM, and the cobblestone-vibration while accelerating as well. Did you ever figure out what was wrong with yours?
fuel pressure or leaking fuel injector(s) would be my suggestion to check. Fuel has to be a fine spray to work in the DI engine. Liquid fuel does not burn, smells like gas in tailpipe and oil. I have the problem too. Replaced engine at 80000 miles, replaced 4 injectors so far and it started again. I changed oil to get the fuel out, will have an independent ASI shop look at it since the dealer has not succeeded in fixing it long term.
Had the wave plate issue at 116,000 miles on my 2010 Outlook. Tranny was rebuilt and everything was fine for about 2,000 miles. Started acting like previous owners said ie... speedo jumping, tach reading erratic due to tranny shifting up and down and poor mileage. Shop checked it out and determined that a bad torque converter was at fault. Fixed under the tranny warranty free. Was still working fine when the timing chains failed at 223,000. Bought new Acadia Limited to replace it.fuel pressure or leaking fuel injector(s) would be my suggestion to check. Fuel has to be a fine spray to work in the DI engine. Liquid fuel does not burn, smells like gas in tailpipe and oil. I have the problem too. Replaced engine at 80000 miles, replaced 4 injectors so far and it started again. I changed oil to get the fuel out, will have an independent ASI shop look at it since the dealer has not succeeded in fixing it long term.
Just joined I have a 12' SLT FWD With the same issues the spark plug tubes that are molded into the head are leaking into the plug wells and they will eventually fill up with oil fouling the plugs out over time only fix gm has proposed is head replacement others vaccum sealant into the area to fix this issue shade tree style.Girl friend has same vehicle you do and same thing was happening. Hers had 147k miles so I changed spark plugs so far its running better one problem I notice was Oil inside the spark plug tubes which could be from manifold or a bad head gasket. But here are somethings that can cause it... Spark plugs, Coils (normally you will see rpm issues more often if its coil issue), fuel filter, Head gasket, transmission issue ie slipping. The engine is 3.6 V 6 acadia AWD.
People Suggest the wave plate but I've come to find torque converter issues in my research be the culprit.Hello, I have also started feeling very similar symptoms to this, surging, bouncing RPM, and the cobblestone-vibration while accelerating as well. Did you ever figure out what was wrong with yours?
Has anyone fixed this issue? Currently having the same issue regardless of speed, weather, engine temp, always randomly. 3.6l fwd denali 135xxx miles with no warranty. Have 3 kids and another on the way. Need help asap. Plz and thank you
Is the check engine light on?
no check engine light
It's your coil pack trust me mine did the exact same thing.
I have a 2012 Acadia Denali that was experiencing the same issue rpm fluctuation under load. Thinking it was a gas/air mixture issue I tried swapping coils, spark plugs, cleaning gas tank, and cleaning the throttle body. It helped, but did not resolve the issue. There were no engine lights so I had nothing to go on.Has anyone fixed this issue? Currently having the same issue regardless of speed, weather, engine temp, always randomly. 3.6l fwd denali 135xxx miles with no warranty. Have 3 kids and another on the way. Need help asap. Plz and thank you
The Acadia has 195,000 miles contemplated cutting my losses and purchase a new vehicle. Then a few days ago the transmission started slipping and shuttering. Had a local transmission shop diagnose and they quoted me $2800 to rebuild both the torque converter and transmission.
I had a great conversation with the owner which said the RPM fluctuation was caused by the torque converter friction plate. The failing parts inside the torque converter created debris that damaged the transmission. I am happy to report since the repair the car runs better than it has in years. I am no mechanic, but I would recommend having someone investigate the torque converter. Hope this helps!
Has anyone corrected this problem for you? I have a 2012 SLE that's having the same symptoms that your reporting for your vehicle. So far I could only find 2 causes for this, 1 the throttle body replacement and the time control module/bank 1.I’ve seen posts similar to this issue I’m experiencing but wanted to throw out my experience. It started with noticing my car feeling like it was jumping slightly while in cruise or sometimes when I’m pressing the Accelerator. I recently notice my RPM bouncing up and down very noticeable when in cruise or any other time really. Gas Milage is horrible now as well. Got the oil changed and put fuel injector cleaner and it seemed to act better but soon (few days of driving) symptoms returned. Took it to a state park with many steep hills with speed limit of 15 and at two points when going up the steepest it felt like it was going to choke out and die but I gassed it and it went away. I drive it daily in home health and noticed it getting worse with the engine jerking couple days ago it felt like I was driving on a cobble stone road when trying to accelerate onto the highway but after pressing gas harder it stopped. took it to mechanic not throwing any codes.
When my 2009 Buick Enclave transmission was rebuilt at 72,000 miles, they replaced the torque converter with a remanufactured unit, as well as clutches, TCM, etc. If the rebuild happened at over 195,000 miles I wouldn't be that upset, but mine happened at just 72,000 miles. And that's with transmission fluid changes every 25,000 miles.
Our 2012 with 125k had no issues, at all. Had annual inspection, recommended to replaced spark plugs under regular maintenance, we brought it back for the spark plug work 2 weeks later (still no issues when dropped off). Of course it started doing what everyone has described the very next day after spark plugs were changed. Of course with No codes! Over 5 trips back to the mechanics and even 2 trips to a new shop. Oil and Fluids have been changed several times, would work great for a few days. Then right back to doing it. So i read what everyone has been saying. From coil to converter. I was hoping to see a uniformed answer on this forum. Guess we will have to start small and go from there. Ugh.
Having the same problems , It is time to change spark plugs, But am having the exact same issue , what gets me is there is no codeOur 2012 with 125k had no issues, at all. Had annual inspection, recommended to replaced spark plugs under regular maintenance, we brought it back for the spark plug work 2 weeks later (still no issues when dropped off). Of course it started doing what everyone has described the very next day after spark plugs were changed. Of course with No codes! Over 5 trips back to the mechanics and even 2 trips to a new shop. Oil and Fluids have been changed several times, would work great for a few days. Then right back to doing it. So i read what everyone has been saying. From coil to converter. I was hoping to see a uniformed answer on this forum. Guess we will have to start small and go from there. Ugh.
Yup crazy, since i posted this it has become worse. We spoke to transmission companies they all said the same thing, which is to do a complete trans replacement torque converter included because if we only do the torque converter and it is the transmission we're almost paying double. Sooo yeah that sucks.Having the same problems , It is time to change spark plugs, But am having the exact same issue , what gets me is there is no code
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