Fuel Injectors
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Fuel Injectors
Does anyone know if re-programming/re-adapting new fuel injectors is needed on these cars? I have a 2017 E300 M274 engine and i'm getting codes for running too rich. Did some tests and turns out two of my fuel injectors are leaking and need to be replaced with OEM injectors.
I looked at the repair manual for the M274's and I couldn't find if they need to be re-learned or programmed again. I would think that they should be plug and play since they get a signal from the ECU and that's what tells it when to spray and the pattern, no?
I looked at the repair manual for the M274's and I couldn't find if they need to be re-learned or programmed again. I would think that they should be plug and play since they get a signal from the ECU and that's what tells it when to spray and the pattern, no?
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Quick update for anyone asking themselves the same question: you have to change the fuel injector numbers in the ECU per cylinder number. So if you've replaced the fuel injector on Cyl #1, you will have to change the fuel injector number in the ECU. You can either have Mercedes do this or you can do it with your Autel OBD II tool. You'll then have to reset your fuel pressure values and that's it.
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2019 E 450, 2016 E350 4matic (retired), 2018 Ford Edge Sport, 2008 Porsche Boxster
Does anyone know if re-programming/re-adapting new fuel injectors is needed on these cars? I have a 2017 E300 M274 engine and i'm getting codes for running too rich. Did some tests and turns out two of my fuel injectors are leaking and need to be replaced with OEM injectors.
I looked at the repair manual for the M274's and I couldn't find if they need to be re-learned or programmed again. I would think that they should be plug and play since they get a signal from the ECU and that's what tells it when to spray and the pattern, no?
I looked at the repair manual for the M274's and I couldn't find if they need to be re-learned or programmed again. I would think that they should be plug and play since they get a signal from the ECU and that's what tells it when to spray and the pattern, no?
Out of curiosity, how many miles are on your car when you received the code that the engine was running too rich?
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W221/W222/W213/X290
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Does anyone know if re-programming/re-adapting new fuel injectors is needed on these cars? I have a 2017 E300 M274 engine and i'm getting codes for running too rich. Did some tests and turns out two of my fuel injectors are leaking and need to be replaced with OEM continental injector.
I looked at the repair manual for the M274's and I couldn't find if they need to be re-learned or programmed again. I would think that they should be plug and play since they get a signal from the ECU and that's what tells it when to spray and the pattern, no?
I looked at the repair manual for the M274's and I couldn't find if they need to be re-learned or programmed again. I would think that they should be plug and play since they get a signal from the ECU and that's what tells it when to spray and the pattern, no?
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On the M274, the fuel injectors aren’t just simple plug and play parts, they each have a calibration code that the ECU uses to adjust fueling precisely. When you replace them, the new injector codes need to be entered into the ECU with diagnostic software (Xentry or a compatible tool). Without coding, the engine may run rich or lean because the ECU is still compensating for the old injector flow rates. So yes, reprogramming or readapting is required
when fitting new OEM injectors on your E300.
when fitting new OEM injectors on your E300.
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Does anyone know if re-programming/re-adapting new fuel injecteur renault is needed on these cars? I have a 2017 E300 M274 engine and i'm getting codes for running too rich. Did some tests and turns out two of my fuel injectors are leaking and need to be replaced with OEM injectors.
I looked at the repair manual for the M274's and I couldn't find if they need to be re-learned or programmed again. I would think that they should be plug and play since they get a signal from the ECU and that's what tells it when to spray and the pattern, no?
I looked at the repair manual for the M274's and I couldn't find if they need to be re-learned or programmed again. I would think that they should be plug and play since they get a signal from the ECU and that's what tells it when to spray and the pattern, no?
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Joined: Aug 2019
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From: USA to Germany
W221/W222/W213/X290
On the 2017 E300 with the M274 engine, new fuel injectors do need to be coded or adapted to the ECU. Each OEM injector has a calibration code that tells the ECU its precise flow characteristics for accurate fueling and idle control. If you install new injectors without entering these codes or performing adaptation, the car may continue to run rich or show imbalance between cylinders. After replacement, use a diagnostic tool like Xentry or a compatible scanner to input the new injector codes and perform the injector quantity learning/adaptation procedure. Once that’s done, your fueling and trims should normalize.
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