Is my car tuned?
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C43 AMG
Is my car tuned?
I have a 2018 C43 that I bought over the summer last year and the car has been rock solid and a total joy to have. I transferred my plates from my previous W204, so when my registration was up this month I took it to get emissions tested and the O2 Heater, O2, and Cat Sensors all came back in a "Not Ready" state. That was a little odd to me since I regularly drive the car (in varying conditions) and it's never thrown a CEL or other codes. I figured it was a fluke so I left, took it on a pretty spirited drive over the weekend and took it back. Same results. So on my way home I stopped at O'Reilly's and got a relatively cheapish OBDII reader and discovered all three of the above mentioned sensors were outright disabled on the car.
It was at this point my eyebrow raised a little bit--it was odd to me that the sensors were showing disabled but no other codes had been stored on the car (the folks who did my pre-purchase inspection cleared them before I bought it and it looks like it's not thrown any sense). So I started doing some research here and saw some other folks mentioning that an ECU tune--specifically Eurocharged--will disable those particular emissions sensors. I shot an email off to Eurocharged about it with my VIN and haven't really heard anything definitive back yet, but figured I'd see if anyone here had any thoughts/insight. If it does have the tune I'd honestly be thrilled--I'd been considering it anyway, but my most immediate concern is determining why/how these sensors were disabled and getting them compliant long enough to pass emissions.
For whatever it's worth, I also reached out to Renntech and AMR to see if they'd done any work. Renntech says they haven't, no reply from AMR yet.
Thanks all!
It was at this point my eyebrow raised a little bit--it was odd to me that the sensors were showing disabled but no other codes had been stored on the car (the folks who did my pre-purchase inspection cleared them before I bought it and it looks like it's not thrown any sense). So I started doing some research here and saw some other folks mentioning that an ECU tune--specifically Eurocharged--will disable those particular emissions sensors. I shot an email off to Eurocharged about it with my VIN and haven't really heard anything definitive back yet, but figured I'd see if anyone here had any thoughts/insight. If it does have the tune I'd honestly be thrilled--I'd been considering it anyway, but my most immediate concern is determining why/how these sensors were disabled and getting them compliant long enough to pass emissions.
For whatever it's worth, I also reached out to Renntech and AMR to see if they'd done any work. Renntech says they haven't, no reply from AMR yet.
Thanks all!
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C43
Normally you will throw a CEL after approximately 50 miles if your o2 sensors are not working properly. Generally speaking, only stage 2 tunes alter/suppress the o2 CEL due to high flow cats or catless downpipes being required to go stage 2. You may want to check to see if your downpipes are stock and/or if your cats are still on the car (from the top, the driver’s side is pretty easy to see).
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C43 AMG
Normally you will throw a CEL after approximately 50 miles if your o2 sensors are not working properly. Generally speaking, only stage 2 tunes alter/suppress the o2 CEL due to high flow cats or catless downpipes being required to go stage 2. You may want to check to see if your downpipes are stock and/or if your cats are still on the car (from the top, the driver’s side is pretty easy to see).
I'm not opposed necessarily to replacing the sensors if I need to, but at this point I'm just incredibly curious what's actually going on.
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Joined: May 2021
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From: Brooklyn
2018 C43 Coupe
Normally you will throw a CEL after approximately 50 miles if your o2 sensors are not working properly. Generally speaking, only stage 2 tunes alter/suppress the o2 CEL due to high flow cats or catless downpipes being required to go stage 2. You may want to check to see if your downpipes are stock and/or if your cats are still on the car (from the top, the driver’s side is pretty easy to see).
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Joined: May 2021
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From: Plainfield IL
Amg C43
Figure anything out?
there are people who think my car may have been tuned before I bought it used due to my dragy times.
any way to find out.
I’m not sure I want the dealer involved yet.
there are people who think my car may have been tuned before I bought it used due to my dragy times.
any way to find out.
I’m not sure I want the dealer involved yet.
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C43 AMG
Eurocharged did seem to think a reflash back to factory was going to solve the issue, so that looks to be the route to go down. It'll end up costing me the price of the entire tune/handheld from Eurocharged or I can bite the bullet and see if the dealer will reflash it without them having a cow about it..
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C43
Nothing yet. Renntech says they have no record of that VIN, I spoke with AMR a few minutes ago and they're checking now. I talked with Eurocharged on the phone this morning and they said they can't track tunes based on VIN, that they're tied to who originally purchased it, so they can't tell definitively one way or another.
Eurocharged did seem to think a reflash back to factory was going to solve the issue, so that looks to be the route to go down. It'll end up costing me the price of the entire tune/handheld from Eurocharged or I can bite the bullet and see if the dealer will reflash it without them having a cow about it..
Eurocharged did seem to think a reflash back to factory was going to solve the issue, so that looks to be the route to go down. It'll end up costing me the price of the entire tune/handheld from Eurocharged or I can bite the bullet and see if the dealer will reflash it without them having a cow about it..
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C43 AMG
The whole thing has me really stressed out--didn't expect such a dilemma in trying to renew my registration.
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C43 AMG
I have an update in case anyone is interested:
I elected to buy a new Eurocharged tune and immediately after getting it I flashed their tune file on it and found very little change in behavior to the car. Drove it that way for a day or so. Then I re-flashed the stock file on it and it turned into an entirely different car. Much more subdued and generally restrained versus what I'd been used to. I immediately knew at that point I'd been unknowingly driving this car for about a year with a tune already on it. Did some highway driving later that night to try and get the I/M sensors to read and they all promptly changed to a "Ready" state other than the EVAP sensor, but I guess that one is a little temperamental to read sometimes. Anyway, took it and passed emissions this morning since I'm allowed 1 Unready sensor. Got home and flashed back to the EC tune and it immediately felt like the car I knew again.
Thanks everyone who helped me troubleshoot and diagnose this!
I elected to buy a new Eurocharged tune and immediately after getting it I flashed their tune file on it and found very little change in behavior to the car. Drove it that way for a day or so. Then I re-flashed the stock file on it and it turned into an entirely different car. Much more subdued and generally restrained versus what I'd been used to. I immediately knew at that point I'd been unknowingly driving this car for about a year with a tune already on it. Did some highway driving later that night to try and get the I/M sensors to read and they all promptly changed to a "Ready" state other than the EVAP sensor, but I guess that one is a little temperamental to read sometimes. Anyway, took it and passed emissions this morning since I'm allowed 1 Unready sensor. Got home and flashed back to the EC tune and it immediately felt like the car I knew again.
Thanks everyone who helped me troubleshoot and diagnose this!
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C43
