Chevrolet Malibu Forums banner

41 - 60 of 72 Posts

·
Registered
Joined
·
4 Posts
Just to chime in as another new guy, I just bought my Malibu on Wednesday, it's a 550km trip home, and averaged 51-52 mpg, with two people, a dog, and the car loaded with Costco stuff.

Hopefully you figure out what's going on =[
 

·
Registered
Joined
·
12 Posts
Just to chime in as another new guy, I just bought my Malibu on Wednesday, it's a 550km trip home, and averaged 51-52 mpg, with two people, a dog, and the car loaded with Costco stuff.

Hopefully you figure out what's going on =[
Thanks! What you describe is exactly what I expected and still expect from the car. I would love for my concerns to be proven wrong. I respect the experiences of everyone on the forum, and their points are generally helpful. Your post underscores the variation people can experience; even on a psychological level the difference between 30-35mpg and 50 mpg is huge when you buy the car for mileage. I thank others for providing further context, but I also think it's completely understandable that at this point I'm not satisfied with the particular car I bought. Hoping that changes soon.
 

·
Registered
Joined
·
12 Posts
Still seeing odd results with MPG, though there is some improvement. According to instruments, my highway MPG has increased with the warm weather - not at all unusual to see 50+ MPG. But mileage on city streets is still low, maxing out around 30-35 MPG. I'm at 821 miles total, and the last 133 miles have gotten just under 40 MPG overall, according to the trip calculator. It's getting closer to what I would have expected, but strange that the MPG performance is inverted from what's typical for a hybrid, with much lower MPG on city streets.

I haven't taken it in for service yet. But in reading up a bit, I noticed that the Malibu's two electric motors are optimized for different driving conditions - the 55kW "generating" motor supposedly is optimized for city driving, and the 76kW "motoring" motor is optimized for the highway. Since my car has outstanding performance on the highway and significantly below-par performance in the city, I wonder if the 55kW components are off in some way. (It also seems that the gas engine gets stuck a bit too long in low gear at low speeds, though that's hard to tell.)
 

·
Premium Member
Joined
·
145 Posts
I suspect your car is operating completely normally. I'd recommend looking at the conditions of your city driving. For your city trips, how far are you driving and what is the terrain like (hilly, flat)? And, what is the outdoor temp when you're in the car?
 

·
Registered
Joined
·
92 Posts
As nuts as it sounds, I'm beginning to think the car is very fuel sensitive. On a few occasions, I have been on a freeway commute getting the expected 43 or so highway when I refueled at a Conserve station that is a convenient stop along the way. After this fuel stop, for about 26 miles, the divided highway speeds are 55-65 where I would normally get about 45 at these speeds. Since this station, which used to be a Shell, has become Conserve fuel, when I fuel at this stop I can't even get 40 on that same stretch of highway, and only average 38-39 for the rest of the tank, including city.

After this happened a few times, I decided to fuel across the street at a 76 on the last trip. I immediately got the expected 45 on that same stretch of highway. I just did this last Tuesday and haven't driven the car since, so I'll see how the rest of the tank goes. Temps have been over 60 on my latest comparisons. The last time I fueled at Conserve and couldn't get an average above 40, I put an octane booster in, and it seemed to add about 1 MPG. If I still don't have consistency once summer temps become a little more consistent, I'll experiment with different fuel grades.

As an aside, these Conserve stations have been popping up in S. Ca while also replacing another independent brand the same family owned (USA, stations, I think). They are very much into renewable fuels, and are the only stations that I've ever seen selling E-85. While unleaded regular base stock is unleaded base stock, the additive package can be very different. Conserve fuel isn't listed as a top tier fuel. Top tier fuels are have a level of detergency important for direct injected engines since the intake port isn't being washed with fuel on a direct injected engine.
I'll report my findings once I do a little more testing.
 

·
Registered
Joined
·
12 Posts
I suspect your car is operating completely normally. I'd recommend looking at the conditions of your city driving. For your city trips, how far are you driving and what is the terrain like (hilly, flat)? And, what is the outdoor temp when you're in the car?
We live in Chicago - no real hills to speak of, and traffic is moderate where I drive. My trips on city streets tend to be around 2 miles, under 40mph, no gunning the engine, plenty of chance to anticipate traffic and brake. (Daily round-tip commute is about 4 miles on streets, 15 miles on a highway.) Temps have been pretty warm lately - around 70 in the morning, 80-85 when I drive in the afternoon.

Maybe my city trips are too short, but then how does the car get rated so high for city mileage? 1-2 mile trips are not unusual for city use.
 

·
Premium Member
Joined
·
145 Posts
Mileage on short trips (1-2 miles) really varies. The engine has to kick in at some point to drive the wheels or recharge the battery. And once the engine starts, it has to warm up. If you're on a short trip, your mileage doesn't have time to recover from engine starts.

My mileage on short trips can vary from 30 to 60 mpg over the same route. I hit the higher end of that range when the engine is warmed up and the battery is charged. Mileage is higher and more predictable on longer city trips (3-5 miles). My average city mileage is probably around 50 mpg, but that's an average of trips of different distances.

This is just how advanced hybrids work in the real world. I'd recommend monitoring your Drive Cycle Info display in the DIC. The display really helps understand how mileage varies during a trip.
 

·
Registered
Joined
·
12 Posts
This is just how advanced hybrids work in the real world. I'd recommend monitoring your Drive Cycle Info display in the DIC. The display really helps understand how mileage varies during a trip.
You're probably right, and I've been paying a lot of attention (probably too much!) to the drive cycle info. The city portion of my drives is usually around 24-30MPG.

This morning I tried resetting the "Trip B" display after each portion of my commute, to see how it's all adding up. (I left out the first 10 minutes to give the engine time to warm up.) First 2 miles on city streets was 30MPG; next 7 miles on a stretch of highway (speed limit 55) was about 49MPG; the last 1.2 miles or so used the fully charged battery, and read as 99.9MPG (!). The end-of-trip readout was 42.5MPG (probably dragged down a bit more by that first 10 minutes). So it's absolutely getting closer to expectations, to the point where my previous criticisms are just about addressed.

I would still say that given the official estimate and what I've researched about other hybrids, it seems strange that on balance, my normal city driving is dragging down what I'm getting from the highway. But this has become more of a quibble, and hopefully it will fade further as the car gets into its groove. I appreciate the feedback. My takeaway at this point is that not only are all cars different, but some require more patience than others.
 

·
Registered
Joined
·
69 Posts
Just turned 4k on our 2016 which we bought December 30, 2016. Overall mileage is 40.4. Not bad considering we live in central (read cold....) WI. Just finished a 140 mile highway trip, kept it at 69, got 48.9.
 

·
Registered
Joined
·
23 Posts
Does anyone ever see their battery gauge fill up the "second" / top battery on the interface? Mine rarely fills up more than a single bar out of the 4 bars in the top battery (like never). I'm wondering if this is normal. My mileage is only good if I barely touch the throttle which leads me to think that the cells are malfunctioning or not getting charged.
 

·
Registered
Joined
·
69 Posts
Does anyone ever see their battery gauge fill up the "second" / top battery on the interface? Mine rarely fills up more than a single bar out of the 4 bars in the top battery (like never). I'm wondering if this is normal. My mileage is only good if I barely touch the throttle which leads me to think that the cells are malfunctioning or not getting charged.
I have seen the entire "upper" battery filled on occasion, and often see it filled to one or two below the top level.
 

·
Premium Member
Joined
·
145 Posts
During highway driving, my battery charge stays around mid-point on the graph. In city driving, battery charge varies from 3 bars to fully charged. The hills we have in Seattle provide a great opportunity for brake regen to recharge the battery. So, I frequently hit full charge if I'm going downhill.
 

·
Registered
Joined
·
12 Posts
Does anyone ever see their battery gauge fill up the "second" / top battery on the interface? Mine rarely fills up more than a single bar out of the 4 bars in the top battery (like never). I'm wondering if this is normal. My mileage is only good if I barely touch the throttle which leads me to think that the cells are malfunctioning or not getting charged.
This is one of the things that bugs me about my so-so city mileage. I basically never get above half-charged in city driving; it only gets in the upper range during highway driving and during long brakes slowing down from the highway. The highest I've ever gotten is 1 bar from the top; it's more common to end the highway portion of a drive 2 or 3 bars above the halfway mark.

I've read (maybe here) that to prolong battery life, the hybrid is designed not to get too close to a zero or full charge. But I would definitely get better city mileage if it got into the upper range more often.
 

·
Registered
Joined
·
253 Posts
...I frequently hit full charge if I'm going downhill.
I noticed when re-genning down long hills with the cruise set while in Colorado that when my battery hit "full" before I got to the bottom, the drivetrain would start making a fairly noticeable buzzing sound that could actually be felt as a minor vibration throughout the car. I wondered at the time if maybe the car was engaging the not-running engine as a mechanical brake just to maintain the cruise set speed once the battery was "full" and re-gen was no longer possible. Have you ever noticed anything like that when your battery is full?



This is one of the things that bugs me about my so-so city mileage. I basically never get above half-charged in city driving; it only gets in the upper range during highway driving and during long brakes slowing down from the highway. The highest I've ever gotten is 1 bar from the top; it's more common to end the highway portion of a drive 2 or 3 bars above the halfway mark.

I've read (maybe here) that to prolong battery life, the hybrid is designed not to get too close to a zero or full charge. But I would definitely get better city mileage if it got into the upper range more often.
The battery graphic represents the battery's S.O.C. between 20% and 80%, not between zero charge and full, so GM has already taken care of your battery for you. The car won't generally violate the battery's 20-80% S.O.C.
 

·
Premium Member
Joined
·
145 Posts
I noticed when re-genning downhill with the cruise set while in Colorado that when my battery hit "full" before I got to the bottom, the drivetrain would start making a fairly noticeable buzzing sound that could actually be felt as a minor vibration throughout the car. I wondered at the time if maybe the car was engaging the not-running engine as a mechanical brake just to maintain the cruise set speed once the battery was "full" and re-gen was no longer possible. Have you ever noticed anything like that when your battery is full?
Yes, I get that noise if I'm in L2 drive mode, braking downhill and the battery is charged. In this case, I believe the drive motor spins up to draw power from the motor/generator that's charging the battery. This keeps the battery from getting overcharged. The engine may spin too, based on an article I read. The noise goes away if I shift to standard "D" mode with a lower level of regen braking.
 

·
Registered
Joined
·
23 Posts
Hm. So the take away for folks like me is YMMV? Can this be checked somehow with a diagnostic of some sort? I'm not complaining. I don't see any problems but I am just a wee little bit underwhelmed is all.
 

·
Registered
Joined
·
253 Posts
Yes, I get that noise if I'm in L2 drive mode, braking downhill and the battery is charged. In this case, I believe the drive motor spins up to draw power from the motor/generator that's charging the battery. This keeps the battery from getting overcharged. The engine may spin too, based on an article I read. The noise goes away if I shift to standard "D" mode with a lower level of regen braking.
Wheew! I was worried that there was something nasty going on. I've never experienced that effect when home in Wisconsin as the topography is relatively flat in our area. Adding to my worry was the fact that I don't remember seeing that noise/vibration described anywhere in the owner's manual. I hope it didn't cause any harm...it sure was disconcerting.



Hm. So the take away for folks like me is YMMV? Can this be checked somehow with a diagnostic of some sort? I'm not complaining. I don't see any problems but I am just a wee little bit underwhelmed is all.
On a recent trip from Milwaukee to Denver (uphill, into a head wind) and back (downhill, but also into a headwind) the MH got 41.7 mpg. The ambient weather/traffic/topography will always cause the Hybrid's economy to vary wildly. I just drove to my dealer to drop off the MH (about 25 miles...all of it uphill). I have normally gotten 43-44 mpg on that run, but today the temperature was mid-70s and the traffic lights were cooperating a bit...and I got 49.6 mpg. While I was there I was talking to the service writer (who also has a new Hybrid). Turns out he lives near me, so I asked him what mileage he gets going to work and he says he usually gets around 44 going uphill to the dealership and about 52 going back downhill on the way home. He did say that during the coldest weather he was seeing around 38 mpg. My experience is fairly similar. My '17 Volt's battery S.O.C. seems to be affected similarly by terrain, temperature, etc. I'm not aware of any test they can perform to specifically check fuel economy. All they can do is scan for any codes that may have been tripped.
 

·
Registered
Joined
·
310 Posts
Had to share. Yesterday, I filled up the tank on the malibu (which is painless compared to the same procedure on my Avalanche) and took my beautiful young bride on a drive to go wine tasting.

While driving (near Temecula, for those in Southern California) I noticed my mileage was not what I thought it would be. I had been almost all highway and only streets for about three miles. Yet, I was below 40 MPG. Interesting.

I did see the computer creep above 40 today after my commute.
 

Attachments

·
Premium Member
Joined
·
145 Posts
So, let me get this straight. According to the photo, you're driving over 85 mph and you're complaining about your gas mileage? You have got to be kidding. Try going 65 mph and get back to us.
 

·
Registered
Joined
·
310 Posts
So, let me get this straight. According to the photo, you're driving over 85 mph and you're complaining about your gas mileage? You have got to be kidding. Try going 65 mph and get back to us.
I was wondering if someone would state that. Actually, 85-90 is normal highway speed outside of Los Angeles. Of course, my AVERAGE speed is more like 25-35 on the highway.
 
41 - 60 of 72 Posts
Top