New GM problems. GM turbo 4 cyl engines and broken vacuum pumps.

Joined
May 25, 2021
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59
Have a 17 Malibu with the 1.5 Turbo in the shop, symptoms are hard brakes, engine light on with many codes, vehicle stalled at same time brakes got hard. Checked fluids, coolant in full cold range, oil just on the tip of the stick. Added a qt, now 1/2 qt under full. Start engine, yeah brake pedal hard and vehicle difficult to stop. Get it in the shop and start poking around, no external vacuum leaks I can see or hear. Connect fluid extractor to the brake booster, booster is good, cross reference engine codes against tech bulletins, find that these are know to shatter the vacuum pump drive resulting in damage to the camshaft including a no start or long crank no start condition due to the exhaust camshaft position reluctor getting damaged by chunks o pump. I guess this is a newer problem, car was indeed a no start when I came back to pull it out, I had to unplug the exhaust cam position sensor to fail it over to get the engine to start.

Anyone here with a GM turbo 4 cylinder, change your oil early and often I guess. The engine oil lubes the vacuum pump I hear, I've seen some Ford vacuum pump failures but they just wiped out the wipers in the pump, they didn't shatter the drive of the pump and possibly eat the end of the camshaft and poop debris all into the cylinder head. Good news is this customer has an extended warranty from CarMax, bad news is they're probably going to bounce her for missed oil changes. OCI on the DIC says 0% oil life and there's no sticker on the glass.
 

CKN

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Yikes, that’s rough. I think there are a lot of people who are clueless about caring for their 🚗.
Many people have enough sense to follow the OLM. It makes it really easy to get regular oil changes. There will always be a few owners who will drive something until it breaks with little to no maintenance.
 
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a 1.5 T-GDI engine wont be as forgiving as previous port injected 4 banger for sure.

Were these also the engines that were melting pistons due to LSPI?
 
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Did some work on my friend's car over the last few days. The oil was off the dipstick even though the OLM indicated that there was lots of life left.

The OLM does not keep tabs on the level, and so unfortunately can make the driver think that all's well when it's not.

As well, I accept that the OLM does a good job when the car is not low on oil, but if the oil is low I suspect the remaining oil gets beat up quickly, shortening its life beyond what the OLM algorithm would predict. In this case, 2.5 - 3 litres of oil was doing the lubricating and cooling work of 5 litres.

I wonder if this type of failure also affects the new 2.7T truck engine. 😲
 

CKN

Joined
Oct 14, 2014
Messages
7,155
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Did some work on my friend's car over the last few days. The oil was off the dipstick even though the OLM indicated that there was lots of life left.

The OLM does not keep tabs on the level, and so unfortunately can make the driver think that all's well when it's not.

As well, I accept that the OLM does a good job when the car is not low on oil, but if the oil is low I suspect the remaining oil gets beat up quickly, shortening its life beyond what the OLM algorithm would predict. In this case, 2.5 - 3 litres of oil was doing the lubricating and cooling work of 5 litres.

I wonder if this type of failure also affects the new 2.7T truck engine. 😲
Very, very few newer vehicles need oil between oil changes. I realize the Jalopies with 200,000 or 300,000 miles owned by some on here probably burn oil like a fireplace burns wood. Those on here who actually work on vehicles and are certified mechanics see very few motors blowing up due to lack of oil..yea it happens. Just not often. You know the 2.7 is a BRAND NEW motor...so we will see.
 

Bitter

Thread starter
Joined
May 25, 2021
Messages
59
Very, very few newer vehicles need oil between oil changes. I realize the Jalopies with 200,000 or 300,000 miles owned by some on here probably burn oil like a fireplace burns wood. Those on here who actually work on vehicles and are certified mechanics see very few motors blowing up due to lack of oil..yea it happens. Just not often.
Oh no, it's way more often then you'd think and it's actually been getting worse over the past 5-8 years! We've seen 3 Hyundai/Kia this year so far with internal engine carnage due to lack of oil and several more with nothing showing on the dipstick due to oil consumption, they've got a bad problem with their engines for some reason. Some are just fine, but they tend to be vehicles with religous oil changes using decent oil. I've seen it especially bad with the Korean twins, but I've seen it with a few Toyota (GR series especially!), GM's newer Eco-Tec lineup and the 'high feature' V6's (2.8, 3.0, 3.6) to a lesser extent. Ford seems to be doing OK as does Jeep, those are usually neglect issues.

Pretty much all the other brands are showing issues with this as well, I suspect it's a combo of low tension rings, PCV system design issues, and probably some pretty low quality oil from quicklube places. It doesn't feel like anyone makes a 'good' engine right now, some nice looking cars that drive well but it feels like the parts under the hood are just sub-par. Maybe it's my old-man kicking in but 'things used to be better darnit now get off my lawn'.
Does the GM OLM show negative miles? :unsure:

Honda will actually display a negative number if you wait too long to change the oil :alien:

Nope, once it hits 0% that's all. I might be able to see a negative value in scan tool data but I didn't get that far into it. Also I may have forgotten to mention on the writeup it was low on oil and that I added oil and instead stated that the oil level was fine and the condition good, if they want to send out a warranty inspector it's on them to see that the OLM is at 0%. Actually the oil is pretty clean looking just dark and clear, not like some gas engines we see with what looks like sooted up diesel oil. Sometimes it even smells similar, not sure if it's just from being ridden hard and put away wet or if it's DI soot from blow by. I know I see some DI's really rolling coal when they stomp on it to get into highway traffic.



Oh hey, I remembered to find the bulletin! Oh wait it's not even a bulletin yet, just a PI. Hopefully a recall before someone gets killed but then again it is GM and usually takes a lawsuit to get them to do anything about anything.
Check out that pump drive! This engine looks nearly the same as their example photo. If they'd just used some kind of intermediate material like nylon or glass reinforced nylon as a shear away they could have avoided damage to the cam and a shattered pump drive. I'd rather have a few chunks of plastic in my oil pan than shards of what looks like powdered sintered steel!
 
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Joined
May 18, 2015
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Have a 17 Malibu with the 1.5 Turbo in the shop, symptoms are hard brakes, engine light on with many codes, vehicle stalled at same time brakes got hard. Checked fluids, coolant in full cold range, oil just on the tip of the stick. Added a qt, now 1/2 qt under full. Start engine, yeah brake pedal hard and vehicle difficult to stop. Get it in the shop and start poking around, no external vacuum leaks I can see or hear. Connect fluid extractor to the brake booster, booster is good, cross reference engine codes against tech bulletins, find that these are know to shatter the vacuum pump drive resulting in damage to the camshaft including a no start or long crank no start condition due to the exhaust camshaft position reluctor getting damaged by chunks o pump. I guess this is a newer problem, car was indeed a no start when I came back to pull it out, I had to unplug the exhaust cam position sensor to fail it over to get the engine to start.

Anyone here with a GM turbo 4 cylinder, change your oil early and often I guess. The engine oil lubes the vacuum pump I hear, I've seen some Ford vacuum pump failures but they just wiped out the wipers in the pump, they didn't shatter the drive of the pump and possibly eat the end of the camshaft and poop debris all into the cylinder head. Good news is this customer has an extended warranty from CarMax, bad news is they're probably going to bounce her for missed oil changes. OCI on the DIC says 0% oil life and there's no sticker on the glass.
I got more and more worried until I read the last part.

Small TGDI engines, and long intervals do not work out. Luckily my Cruze consumes an unmeasurable amount of oil, but my interval is short anyways. That makes me wonder how long she really went. I've never come across an GM SGE engine that consumes much oil.
 
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