Tune up Turns on CEL (2016 CX-5)

Took my 2016 CX-5 to a local shop for a tune up. Trusted mechanics, good guys, worked on my cars for years without issue. I just bought the vehicle a few months ago with 92,000 miles on it and took it in for an oil change, spark plugs, air filter, and general maintenance. They took care of it for me, but I have had two things happen. First, as I left the lot, after the mechanic having just test drove it, I noticed that my blinkers didn't work. I pulled back in, we did a little messing around with plugging and unplugging to no end, and then finally just disconnected the battery and reconnected it after about a minute. That solved the issue. The car ran fine through a ten mile drive with no issues. I get back in my car to go ten miles home about 4 hours later and the CEL light comes on. Codes are P0102, P0113, P061B, and P0421. They all relate to air flow the way it seems, but I know just about enough to be dangerous in this situation. I looked things over a bit and did not see anything egregious. Opened the air filter box and made sure it was sealed tight when I put it back together is about all I did. Any thoughts on what might have triggered this after a basic tune up?
 
Someone else had a similar sounding issue. It ended up being a bad temp sensor, possibly pulling down the 5v reference so that the other sensors gave bad readings. Check your engine wiring for breaks or a short. Especially near the affected sensors and coil packs.
 
I'm surprised that a shop would mess around with electricals like that without first disconnecting the battery, however that probably wasn't what caused those codes to be set. I've read multiple reports of 'quick' battery disconnects causing all sorts of random codes to be set, as a result of the caps not draining. So one very easy thing to try is disconnecting the battery and keeping it disconnected for a longer period of time - overnight is the easiest way for most owners.
 
edmaz,
I was thinking about the same when I read "after about 1 minute".

To OP,
Please disconnect the (-) terminal of the battery for at least 10 minute to draw all the charges in any forms of capacitors. Make it 30min if you are not in a hurry. Do a full reset.
(Auto-up windows (if equipped) might need to be reset ... etc.)
Let us see if that fixes everything.
 
Took my 2016 CX-5 to a local shop for a tune up.
That should trigger a red flag right there.
Modern cars don't need "tune ups". As soon as a shop or dealer says you need a tune up, turn around and walk away.
Tune ups were meant for older cars, when leaded gas was still being used, and ignition systems consistent of a distributor, rotor, cap, points and plug wires. It also harkens back to the days of carburettors, and winter and summer thermostats. None of that stuff is relevant today.
Change your oil regularly, rotate your tires, and replace spark plugs at around 100,000 miles. Done.
 
That should trigger a red flag right there.
Modern cars don't need "tune ups". As soon as a shop or dealer says you need a tune up, turn around and walk away.
Tune ups were meant for older cars, when leaded gas was still being used, and ignition systems consistent of a distributor, rotor, cap, points and plug wires. It also harkens back to the days of carburettors, and winter and summer thermostats. None of that stuff is relevant today.
Change your oil regularly, rotate your tires, and replace spark plugs at around 100,000 miles. Done.
Interesting. I took it there for scheduled maintenance and they did that. The fuel system cleaner was their addition. The codes have cleared with the exception of a catalytic converter code. They have given ma a catalytic converter cleaner product to try, but in the end think I may need a new catalytic converter. The owner is talking with his chemical sales rep and supervisor regarding the potential that the intake cleaner caused the issues. They seem to be admitting a little responsibility, but I also appreciate the advice on the tune up.
 
edmaz,
I was thinking about the same when I read "after about 1 minute".

To OP,
Please disconnect the (-) terminal of the battery for at least 10 minute to draw all the charges in any forms of capacitors. Make it 30min if you are not in a hurry. Do a full reset.
(Auto-up windows (if equipped) might need to be reset ... etc.)
Let us see if that fixes everything.
I did this for about 45 minutes last week. The catalytic converter code has remained. You mentioned the auto window reset. Mine stopped working. What is the process to reset the auto function (all windows still go up and down).

Clint
 
.... The owner is talking with his chemical sales rep and supervisor regarding the potential that the intake cleaner caused the issues. They seem to be admitting a little responsibility ...
Good to read they're being upfront about this situation, which could also translate into you getting financial help with the cat replacement (if that's what actually happens).

Here's something for you to try. It's possible that the intake cleaning they did resulted in containments travelling into the cat. So IMO it's worth a shot to do a series of Italian tune-ups, with the goal of burning/blowing out whatever might be in the cat. Find a high-speed highway with light traffic, do that 10 times or so, and see if it brings any joy.
 
Or it took out O2 sensor

Screenshot 2023-06-03 at 8.18.01 AM.png
 
Or it took out O2 sensor ...
Yes, that's possible as well, and I actually did replace the far less expensive O2s for a cat code in the past myself. My try was unsuccessful, as are most of them, but doing so is no big expense for a DIYer. However, I suspect that most shops wouldn't take that approach, unless the owner requests, and pays for it.
 
Update.... After two tanks of gas and a bottle of catalytic converter cleaner, we are left with only the P0421 code. The mechanic is now expecting to replace the converter. Is this something that I should be asking for compensation for? It seems like more than a coincidence that the converter became a problem directly after the tune up. He hasn't offered it, and I haven't asked for anything yet. Thoughts?
The car does have almost 100,000 miles on it. Is it possible that the converter is simply worn or clogged by use and time and is meant to be replaced? I've never had to replace one on a vehicle before so I am not aware of what this repair entails.
 
Good to read they're being upfront about this situation, which could also translate into you getting financial help with the cat replacement (if that's what actually happens).

Here's something for you to try. It's possible that the intake cleaning they did resulted in containments travelling into the cat. So IMO it's worth a shot to do a series of Italian tune-ups, with the goal of burning/blowing out whatever might be in the cat. Find a high-speed highway with light traffic, do that 10 times or so, and see if it brings any joy.
The italian tune up 10x over is truly such bad advice. You'll only be shoving more partially unburnt fuel down the exhaust system in doing that.

1-2 pulls to BEFORE redline, with fuel system cleaner, maybe once a month is all you would ever need.

I doubt it would solve OP's problem. Likely just an o2 sensor.
 
Back