P0420 Code on Chevy Trax 1.4L Turbo 

Thanks for this! I looked at this pipe initially, and saw a flange-ring completely rusted off. I didn't see any holes or cracks there. Saw this video and decided to double check that area. There was a small area letting exhaust out. Side note, I'm at about 40000 miles or around 64000 km. Ugh

That makes way more sense. I have a exhaust leak for a couple months I’ve noticed in the morning. Bottom heater core hose blew up yesterday so it is getting hot by the back of the engine. Thanks for the video, I think this could be my problem also. Way better than $1500 at the dealer

Thank you so much, your video helped me diagnose the trouble in my car too.

I have a 2014 Chevy Cruze with 1.4L engine it has 180,000 mile. I have been getting a P0420 code. I would go away and come back. I fixed it just by disconnecting the Negative side on the battery 1st. Now find the computer it’s on the side where the battery is. It’s has 3 connectors on it. I disconnected all 3 connectors and cleaned each side male and female connector with CRC 05103 QD Electronic Cleaner. Let it dry 15 minutes. I plugged all 3 back in. I installed negative battery cable. I started and drove the car 50 miles. It never came back.

If it helps, Federal emissions laws require carmakers to cover the catalytic converter and PCM/ECM (powertrain or electronic control module) under warranty for eight years or 80,000 miles, whichever comes first. The dealer replaced mine for free no questions asked on my 7 year old Cruze with 72k miles.

My PO420 was the flex pipe on my 2016. $386 later it’s fixed. Mine has under 50,000 miles. Just waiting for the next thing to break!

I have the same engine size in a 2015 buick encore. Engine light on change the both O2 Sensors...Never thought about the flex pipe. .before I purchased the catalytic converter. Thanks alot

I just got this code after a car wash I have a 2015 Encore how to I check the exhaust connection ? I’ve only had what seems like a worn engine mount which could break the exhaust mount?

I changed the flex pipe it was leaking also changed both sensors running great light out 2015 buick encore

Just for the record its hard to find trax specific info out there, I know its very similar to the cruz, but its nice to see this. Thanks for posting. I changed both o2 sensors and flex pipe. Still hesitation in engine. The P0420 code is still persistent. Just dont get how a cat can go out that fast. Its a 2016. Only 5 years old. Maybe a maf sensor or something?

So I've replaced both my cats and the top o2 sensor in the engine bay and I'm still getting the cat code. My flex pipe is in good condition (just had it off the car while changing converters) and it takes about 45 minutes before the code comes on. Before I throw another $50 at it for the other sensor is there anything else it could be

Having P0420 on Chevy Sonic 2017. Focused on cat began taking that off ( rusted bolts difficulty reaching rear ones) during that couldnt help but notice flex pipe was in really poor condition. It split and fell completely apart. Well finally after buying a saw-saw I was able to get both the flex and cat completely off. The flex was dark inside the cat at intake was dark at substraight and the output looked pretty clear telling me there was significant amount clogged inside. So the new cat apparent to me now... For the hatchback and was completely different in size and shape. Well I have a sedan. So a bit of a delay good news is sedan is half the price. Lesson learned always get eyes on the part before ordering especially expensive ones! Also changing O2 sensors because the car has 110,000 miles. Also have found oil residue in turbo which I believe contributed to this issue over time.. I believe the car takes slightly under 5 quarts of oil and that often 5 is put in that may of increased pressure and caused leakes in seals. And or the very poor engineering with the oil filter being just above the turbo exhaust outlet ? A filter that needs to have guts taken out each time of the reusable shell. Ugh. Oh have to disconnect coolent hoses to get to it as well. Why ? Because the plastic coolan t outlet cracks easy when aged a bit. Certainly wish an aftermarket would make that part aluminum but then again how would I get the guts of the filter out and drip some in the turbo exhaust lol... Sorry I am venting.

My 2016 Chevrolet Spark 1.4L (not turbo) with 135k miles was having P0420 code. Bank 1 below efficiency it says. Having serious RPM flucuations upon acceleration now with no other trouble codes. This sux

Great video. Where is the first catalytic converter located on these cars? Is it before the flex pipe or after? Trying to help out my friend diagnose her p0420 remotely and see if the cat is in a hard spot to replace. Thanks!

if your flex pipe is leaking meaning your putting less bad emission through the 2nd sensor, it would actually help not getting p0420 code, just like putting a spacer on 2nd 02 sensor. its your cat buddy filled up with oil leak from turbo, I've been doing this for 45 years

i have a 2015 trax turbo. it runs fine all the time even when the p0240 code comes on. its only got 30,000 miles on it. i tried cleaning the maf sensor to no avail and risolone cat cleaner..i have a scanner that can clear the light but it always comes back on anywhere between 100-200 miles.. but what is the flex pipe that your suggesting it could be ?

Did this resolve the issue?

My mechanic told me the flex pipe cracking is a common issue on the 1.4L engines.

Does ur engine make a ticking sound when the code was up? Couple of nights ago on my way to work it clicked on the engine light and very faintly I heard a ticking noise few minutes later it jus got louder. I’ve done some research and it says the oil or the same reading as what you said. But I’m not sure if the ticking is from the code being up or if something is blown and it’s giving me that code instead. Anything will help. I’ll change everything if recommended if needed I jus don’t need the headache of a whole motor going out

Hello, I have this p0420 code and thanks to your video I found my flex pipe is cracked.. can you tell me if this cleared the code for you after the replacement? Thanks for your time!

Did you smell sulfur before you changed that out ??

I’m about to lose my mind with my 2015 Chevy Trax. Had the front catalytic converter changed, O2 sensors replaced, multiple types of flushes due to cooling/heating/ air hoses needing done (way over due) and still getting the issue. I do notice that when I try to accelerate my car it doesn’t “punch it” as it were, but it gradually climbs. Will the flex pipe be the main culprit of this too?

a question is it normal for the A / C compressor to be on even though I am not using the A / C in the cabin?

Where can I get the flex pipe for a Chevy trax 2015 lt? Mine is cracked but in the dealership says that they don’t do that piece anymore.

The dealer ship let me put on 2 different after market cats until they told me that it has to be the cat from the factory which would cost 2600

Where did you get the part from I need one and don't want to buy the wrong size for my 2016 Trax

Thanks Paul

Can this cause stuttering on car while driving ?? My vehicle has same code and stutters

Thanks for the video!!! Do u think these cars will last 100k without many expensive mechanical issues?? I've been hearing lots of horror stories of turbos going out and expensive costs at low low miles .. I have 2018 trax with 14 k

Did the flex pipe replacement fixture issue on the Chevy trax?

I changed my flex pipe the whole front exhaust pipe. Because the flex pipe had a whole in it. The code is still popping.

I'm confused. The exhaust flex pipe had completely separated and you never noticed that the car was louder? Wouldn't it sound like a straight piped piece of junk?

I have a red Chevy Trax 2015 I was told my engine is going still paying for this car haven't had it for a year before it gave me hell now I'm stuck paying for a car I can't afford to fix i brought a new converter an muffler think it was the problem but it's still reading 420 my spark plug are a little wet from oil I'm thinking it's my valve seals not sure I've changed water pump , radiator, thermostat, gasket seal an more an still car won't get power but she drives like there is nothing wrong sick of this car but I'm stuck with her so either I fix her or let car get towed an I take a big loss an hit i owe 19 from 28 thousand please help me she blows smoke when I start so we t an put stuff in to stop seal leak I noticed it stopped the smoke. When driving it idles up an act as if it want to stall I haven't changed coil pack yet any thoughts

my 2014 trax has 311,000 km now, my problem is while I'm driving the turbo shuts down, reset code and it works again, it could be 1day or weeks then it does the same, just random times, any help would be appreciated

2012 Cruze, I’m hoping this is my fix. I’m thinking maybe just delete all of this and add an aftermarket exhaust. I imagine it’s going to be around the same price

Hey bud did u happen to fix the oil leaks your self or did you have someone else do that?

Must likely would have that telltale black carbon trail @ the leak.

Did changing the flex pipe solve the p0420 issue?

Did that fixed the problem after changing the flex pipe?

mine was a cracked flex pipe also. replaced it and the light never came back on again.

I like to know about the Chevrolet Trax LT 1.4 liter engine ok

Where can I find the O2 downstream

I changed the whole front exhaust pipe and then the O2 sensors and the code is still popping.

If the flex is downstream of the sensor makes no difference if it's upstream most definitely effects 02 sensors.

Just got the flex pipe on my 2016 chevy trax LT

These turbos go bad also and gunk up the cat.

My wife's the same thing !

Time stamp:250 Hey dude, broken weld.. I’ve got a quick question?

Long winded video talking about everything but the problem

I like to know about the Chevrolet Trax LT 1.4 liter engine ok