CEL after taking in car for service at dealership - Camaro5 Chevy Camaro Forum / Camaro ZL1, SS and V6 Forums

TheSmokingSuns · 02-06-2016, 03:10 AM

Yesterday, I went to take my car in for a coolant change (5 year service), transmission fluid change (100K mile service), and oil change (every 3,000 miles service). Just 3 miles or so after leaving the dealership, the CEL comes on. I immediately go back to the dealership and tell them to check it out. The car came back with code P0420 for Catalytic Converter which is unrelated to the services they did and just called it a "coincidence" and they say it's not their fault. More like a shady coincidence if you ask me. I baby this car with pages of maintenance. Never ever seen the CEL come on during the life of the car from brand new till now. Car was running perfectly before taking it in. They cleared the code and told me to see if it comes back on and it came back on today. The car is bone stock performance wise. Maybe it is a coincidence, but it's just crazy that this happens immediately after getting these services done. Almost like I paid almost $500 to break my car. Any opinions or thoughts if the services performed can in any way interfere / relate with the P0420 code I'm getting? Thanks

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MrChrisLS3 · 02-06-2016, 04:12 AM

The first thing I would check is to see if they might have loosened one of the o2 connections. Maybe moved a wire, or unplugged one for the trans fluid change. These things can happen.

Soybeanrice · 02-06-2016, 04:20 AM

Give your dealership a break. o2 lights are not a problem at all. If youre really concerned, save the labor and do it yourself?

motorhead · 02-06-2016, 04:50 AM

I honestly can't see how what you describe they did as causing that code. unless, they had to do soming with the O2 sensors to perform the transmission fluid change. It could be one of the rear O2 sensors. It will probably come back. That code usually doesn't self correct. Did they put the car back on the lift when you took it back to check the connections at the O2 sensors? Any good dealer would have at least had a look around when something like that happens.

essess · 02-06-2016, 05:05 AM

Cat efficiency codes can only occur if the o2 sensors are functioning properly. Sounds like coincidence to me, theres really no way to cause that by mistake.

motorhead · 02-06-2016, 05:17 AM

Quote:

Originally Posted by essess

Cat efficiency codes can only occur if the o2 sensors are functioning properly. Sounds like coincidence to me, theres really no way to cause that by mistake.

That would I would have thought too. If one was diconnected it would be a difference code right? I had a truck with that code one time and the dealer put new cats on it because they said that had to be the problem with that code. (It was under warranty ) The code came back. They replaced the one rear O2 sensor on that bank and the problem was fixed. They couldn't even explain it.
What about if it was out of range even to see a problem with the cat but not enough to send a O2 sensor fault? While rare, those kind of problem do happen in my world.

Coincidences like that can happen too.

JMT · 02-06-2016, 05:38 AM

If you need new cats it would be a great reason to get Solo hi flow cats installed! Look on the bright side and good luck.

polizzio · 02-06-2016, 05:40 AM

I don't buy coincidence, imo.

Tenring · 02-06-2016, 08:53 AM

Quote:

Originally Posted by Soybeanrice

Give your dealership a break. o2 lights are not a problem at all. If youre really concerned, save the labor and do it yourself?

It is a problem when you take it too emissions or try to use the remote start.

JerTM · 02-06-2016, 09:35 AM

The cat efficiency dtc couldn't be caused by any of the services you listed. It can't be a disconnected o2 either, those would be a circuit dtc. If you did an injector service or another chemical that the engine has to pass through the cylinder while running it's possible that set the dtc.

pyroguy · 02-06-2016, 09:43 AM

Quote:

Originally Posted by JMT

If you need new cats it would be a great reason to get Solo hi flow cats installed! Look on the bright side and good luck.

^ This! Then while you're under there, finish off everything behind the cats with Solo as well. You'll have a new love for your Camaro!

tomlink · 02-06-2016, 10:14 AM

First thing I would do would be to check the oil level. If that checks out I'd look under the car to see if they may have lifted the car on an exhaust component. While this may be a coincidence, I'm with the OP that getting the code right after they work on the car does seem to be a mechanic foul up.

I once got new tires and immediately after starting to move noticed a noise in the front. Seems that the right front wheel had only 1 lug nut on hand tight.

KaBoom1701 · 02-06-2016, 10:18 AM

One more reason not to let anyone else touch your car....do everything you can yourself before you have to take your car into the dealer. Just my .02

MrChrisLS3 · 02-06-2016, 11:28 AM

Quote:

Originally Posted by essess

Cat efficiency codes can only occur if the o2 sensors are functioning properly. Sounds like coincidence to me, theres really no way to cause that by mistake.

Yes and no. The 0420 code is based upon data sent from the upstream sensor compared to the downstream sensor. The ECU will compare these, if they are too similar, it will throw the code. An o2 sensor can be damaged, or improperly connected where it could send false data.

Someone mentioned an exhaust leak, which is a possibility, either at the manifold or the connection to the mid pipe.

Also keep in mind that the OP has a DI engine. He didn't mention the mileage, but higher mileage valve coking and PCV issues could at play here as well. Why right after the mentioned services is a mystery, but anything's possible.

However, if it actually is the converter itself, I believe it should still be covered under the emission warranty. If it were me though, the first thing I would do is get under it and check all the connections, listen for exhaust leaks, and check vacuum hoses and connections. If all of that checked out, I might go to a different dealer that has no dog in the fight and have them check it out. If it turns out that something the first dealer did caused it, I would be armed with this info and go back to the first dealer.

02-06-2016, 03:10 AM	#1
TheSmokingSuns Drives: 2017 Camaro 2SS, 2011 Camaro 2LT Join Date: Jan 2014 Location: USA Posts: 640	CEL after taking in car for service at dealership Yesterday, I went to take my car in for a coolant change (5 year service), transmission fluid change (100K mile service), and oil change (every 3,000 miles service). Just 3 miles or so after leaving the dealership, the CEL comes on. I immediately go back to the dealership and tell them to check it out. The car came back with code P0420 for Catalytic Converter which is unrelated to the services they did and just called it a "coincidence" and they say it's not their fault. More like a shady coincidence if you ask me. I baby this car with pages of maintenance. Never ever seen the CEL come on during the life of the car from brand new till now. Car was running perfectly before taking it in. They cleared the code and told me to see if it comes back on and it came back on today. The car is bone stock performance wise. Maybe it is a coincidence, but it's just crazy that this happens immediately after getting these services done. Almost like I paid almost $500 to break my car. Any opinions or thoughts if the services performed can in any way interfere / relate with the P0420 code I'm getting? Thanks Sent from my iPhone using Tapatalk Last edited by TheSmokingSuns; 02-08-2016 at 01:35 AM.

02-06-2016, 05:40 AM	#8
polizzio Drives: 2012 1LT SIM Camaro Join Date: Sep 2012 Location: Louisiana Posts: 375	I don't buy coincidence, imo. Last edited by polizzio; 02-06-2016 at 05:43 AM. Reason: wrong thread

02-06-2016, 10:18 AM	#13
KaBoom1701 KaBoom1701 Drives: 13' ZL1 Red M6 Join Date: Dec 2012 Location: I.E. SoCal (Yucaipa) Posts: 8,630	One more reason not to let anyone else touch your car....do everything you can yourself before you have to take your car into the dealer. Just my .02 __________________ Mods: Roto-Fab Intake, WW Res. kit & Big Gulp Air Scoop, Elite Catch Can, ATI Super Damper & 18% OD Pulley, LF Idler pulley bracket, Metco CC breather, ID850 Injectors, Stainless Power Headers w/ ceramic coating, TR71X Spark Plugs, JMS Fuel Pump Booster, Bo White TB, Tuned by Ted @ Jannetty Racing, Ron Davis HX, D3 Reservoir, Pfadt 1" Springs, Moreno Camber Plates, ZL1 Addons Splitter guard washers, Tow Hook kit & rock guards, Hurst Shifter Billet Plus 6 Speed Short Shifter, ZL1 DRL lighting harness, ZL1 Recaro Seats.

02-06-2016, 04:12 AM	#2
MrChrisLS3 Drives: 2018 1SS M6 Join Date: Nov 2014 Location: Houston Posts: 2,617	The first thing I would check is to see if they might have loosened one of the o2 connections. Maybe moved a wire, or unplugged one for the trans fluid change. These things can happen.

02-06-2016, 04:20 AM	#3
Soybeanrice Drives: 2014 2SS/RS Join Date: Jun 2013 Location: Orlando, FL Posts: 793	Give your dealership a break. o2 lights are not a problem at all. If youre really concerned, save the labor and do it yourself?

02-06-2016, 04:50 AM	#4
motorhead Drives: Love the one you're with Join Date: Sep 2009 Location: Downtown Charlie Brown Posts: 11,850	I honestly can't see how what you describe they did as causing that code. unless, they had to do soming with the O2 sensors to perform the transmission fluid change. It could be one of the rear O2 sensors. It will probably come back. That code usually doesn't self correct. Did they put the car back on the lift when you took it back to check the connections at the O2 sensors? Any good dealer would have at least had a look around when something like that happens.

02-06-2016, 05:05 AM	#5
essess Drives: 10 camaro ss Join Date: Sep 2014 Location: ri Posts: 79	Cat efficiency codes can only occur if the o2 sensors are functioning properly. Sounds like coincidence to me, theres really no way to cause that by mistake.

02-06-2016, 05:38 AM	#7
JMT Drives: 2013 1LT Join Date: Oct 2013 Location: Panama City Beach, FL Posts: 703 View My Garage	If you need new cats it would be a great reason to get Solo hi flow cats installed! Look on the bright side and good luck.

02-06-2016, 09:35 AM	#10
JerTM Drives: 2011 2SS/RS M6 Join Date: Oct 2015 Location: Utah Posts: 1,940	The cat efficiency dtc couldn't be caused by any of the services you listed. It can't be a disconnected o2 either, those would be a circuit dtc. If you did an injector service or another chemical that the engine has to pass through the cylinder while running it's possible that set the dtc.

02-06-2016, 10:14 AM	#12
tomlink Drives: 2011 Camaro 2LT RS Join Date: Apr 2011 Location: New Bern, NC Posts: 953 View My Garage	First thing I would do would be to check the oil level. If that checks out I'd look under the car to see if they may have lifted the car on an exhaust component. While this may be a coincidence, I'm with the OP that getting the code right after they work on the car does seem to be a mechanic foul up. I once got new tires and immediately after starting to move noticed a noise in the front. Seems that the right front wheel had only 1 lug nut on hand tight.