Just hot weather? Or do I got problems?
- Thread starter PocketRocket
- Start date
Without a doubt the heat is a problem with this car. I'm in Dallas where it's typically around 100 during the day with humidity around 30 to 40%. It's not a happy camper and in fact will occasionally throw a P0299 at me (I think, or P0229.. Either way, the low boost code). I have 108K on mine. Does seem to be okay below 90 degrees. One of those things, I guess...
Of course, the valve cover PCV valve failing every 40K miles is pretty unamusing. Mine just crapped the bed again, so I'll be doing this for the THIRD time. Good thing the covers aren't expensive and the job is pretty straight forward, but what friggin genius engineer puts a life limited part on an engine part that isn't designed to be regularly replaced?!
Of course, the valve cover PCV valve failing every 40K miles is pretty unamusing. Mine just crapped the bed again, so I'll be doing this for the THIRD time. Good thing the covers aren't expensive and the job is pretty straight forward, but what friggin genius engineer puts a life limited part on an engine part that isn't designed to be regularly replaced?!
mysterslyckster
New member
Sonic in heat...
I've had the same issue on mine. 2013 RS Automatic with about 20k on it. These small 1.4 turbos do not like the heat at all. I've installed a boost/vac gauge on mine. I live in the Oklahoma City area and regularly see temps in the 90's to 100's with fair to moderate humidity. Under light to moderate acceleration between 1500-2000 RPM and 30-40 mph, the turbocharger just drops right out until the engine RPM picks back up some. I'll watch the boost gauge peg itself around 2-4 psi boost and just stop like it hit a brick wall. No codes or any other trouble, not even pending codes, just not enough air density with elevated temperatures to keep the turbocharger moving effectively until RPM picks back up. And yes, gets worse with the A/C on and the hotter it gets outside.
If I know I'm going to run into heat problems accelerating through 30-40 mph in that RPM range, I'll put the transmission into manual mode and shift it manually at higher RPM's than the normal shift pattern. No problems at all that way.
I've had the same issue on mine. 2013 RS Automatic with about 20k on it. These small 1.4 turbos do not like the heat at all. I've installed a boost/vac gauge on mine. I live in the Oklahoma City area and regularly see temps in the 90's to 100's with fair to moderate humidity. Under light to moderate acceleration between 1500-2000 RPM and 30-40 mph, the turbocharger just drops right out until the engine RPM picks back up some. I'll watch the boost gauge peg itself around 2-4 psi boost and just stop like it hit a brick wall. No codes or any other trouble, not even pending codes, just not enough air density with elevated temperatures to keep the turbocharger moving effectively until RPM picks back up. And yes, gets worse with the A/C on and the hotter it gets outside.
If I know I'm going to run into heat problems accelerating through 30-40 mph in that RPM range, I'll put the transmission into manual mode and shift it manually at higher RPM's than the normal shift pattern. No problems at all that way.
mysterslyckster
New member
91 Octane is the highest we can get in OK. And yes I use it. About the only thing that will help with this problem is a slightly smaller A/R ratio on the turbine side of the turbocharger to keep the turbo RPM's up at lower engine speed. But the trade-off with that is less overall turbocharger capacity. endtankusa.com used to have a neat looking aftermarket solution to upgrade the stock turbocharger to a small Garrett unit for the 1.4L Cruze. But that website has been down for a couple of years last I looked. Can't find any info on it anywhere. My only gripe with the 1.4L Ecotec is the fact the turbo and manifold are one piece. Doesn't leave much to play with as far as changing to a different turbo. And since this car is a daily driver, no time to experiment with welding up a custom manifold to try. 
The 1.4l Ecotec just doesn't like high heat. Even a larger intercooler won't help here as the turbo itself just stops pushing until you gain back some engine speed.
The 1.4l Ecotec just doesn't like high heat. Even a larger intercooler won't help here as the turbo itself just stops pushing until you gain back some engine speed.
carsNskis
New member
This^
Hood vents could be a good addition if you are ok with the look.
Make sure your coolant is in good shape. Clean the intake air sensor (gently). Perhaps an injector cleaner?
A properly running stock car should be able to handle the heat, even though it may down tune due to less cool and dense air available to start with...
I'd look for restrictions that cause the bog. The ecu is getting feedback from something telling it to back off.
[emoji593][emoji809][emoji472]
Hood vents could be a good addition if you are ok with the look.
Make sure your coolant is in good shape. Clean the intake air sensor (gently). Perhaps an injector cleaner?
A properly running stock car should be able to handle the heat, even though it may down tune due to less cool and dense air available to start with...
I'd look for restrictions that cause the bog. The ecu is getting feedback from something telling it to back off.
[emoji593][emoji809][emoji472]
mysterslyckster
New member
I had the same thoughts two summers ago when I got my MPFab intake. I took the entire intake apart from the filter all the way to the throttle body. Cleaned out all the crap from PCV inlet to the TC compressor intake and also checked the intercooler for restrictions and fouling. the system is spotless. Also running a ZZP cat back exhaust. My wife had her own 2013 RS which stayed stock and did the exact same thing. This engine just has a really bad dead spot in that rpm/speed/load combination and hot weather. Easy enough to get around with some manual shifting.
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I think this is just one of those things. It's a relatively tiny engine connected to a relatively tiny turbo and it just can't get enough air when its a high density altitude day. It's the trade off I get for averaging nearly 42 MPG highway (of which 75% of my driving is). Having the manual tranny makes this at least a bit more manageable as I can keep the car in a higher RPM band and not deal with the slushbox "hunting around" for a gear, but I do find that the M32 gearbox with stock lubricant is a bit "resistant" to shifting smartly. I had my transmission replaced at around 70K miles (car now has 109K) because of the dreaded 6th gear whine. When they replaced it had insisted they service it with the manufacturer suggested fluid volume, not the GM one (which underservices it and exposes the 5th and 6th gear bearing, ultimately leading to it failing).
Anyway, topic drift. This engine + high density altitude = dog. A bigger turbo would probably solve the issue, but would defeat the purpose of a 1.4l engine in this car in the first place. The Sonic is supposed to be an econobox.
Anyway, topic drift. This engine + high density altitude = dog. A bigger turbo would probably solve the issue, but would defeat the purpose of a 1.4l engine in this car in the first place. The Sonic is supposed to be an econobox.
JesusTheAgnostic
New member
It's like 90 something degrees around here between 12 to 4
Sent from my ONEPLUS A3000 using Tapatalk
Sent from my ONEPLUS A3000 using Tapatalk
JesusTheAgnostic
New member
Didn't mean to hit enter. I installed bigger injectors and I have to say it made a nice difference. I also filled her up with E85, that made a huge difference too. 90 degrees and she's pulling like if it was 80.
Sent from my ONEPLUS A3000 using Tapatalk
Sent from my ONEPLUS A3000 using Tapatalk
EyeluvSmegma
New member
I dunno, with a handful of bolt-ons and an aggressive tune, my fuel mileage only goes down when I'm in the throttle. Off the throttle, on a long runs highway mixed with some state roads/stop and go I can average 44mpg. My brothers CRX was supposed to be an econo-box too, but a Frankenstein engine bay and 485WHP later..... Still nets 32mpg.. all in the foot.
I encountered this problem this weekend.
Temps in the upper 90's and cruising the highway. Boost would go non existent and I'd struggle to keep highway speed of 60+. Car made 100 mile trip in the morning with lower temps with no issue. Once temps hit upper 90's and I had AC going on the return trip, boost dropped out about 25 miles in. Stopped for a few minutes at a store and everything was fine afterwards.
Did the same exact thing on the previous day on a separate trip and similar temps.
'15 1.4T auto with 27K
Temps in the upper 90's and cruising the highway. Boost would go non existent and I'd struggle to keep highway speed of 60+. Car made 100 mile trip in the morning with lower temps with no issue. Once temps hit upper 90's and I had AC going on the return trip, boost dropped out about 25 miles in. Stopped for a few minutes at a store and everything was fine afterwards.
Did the same exact thing on the previous day on a separate trip and similar temps.
'15 1.4T auto with 27K