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Hey everyone I am remaking this thread to see if i can get any help with my 2017 c43. To quickly run down my problem I went to fuel up at a crusty looking shell and i was putting 91 and the pump was going extremely slow almost took up to 35-40 mins to fill up and when it felt like it had been too long i went to check outside and i seen it was full and spilling out consistently out the nozzle and i took it out immediately then noticed a bigger detached puddle from directly underneath my trunk. I smelled that puddle and it was fuel as well, i pulled my car forward to a dry spot and watched for a few mins and it didnt leak another drop. Almost immediately driving off i got a check engine light and my car started to shake like crazy. Below i have the OBD scan from autozone and I would really appreciate if any one had any info i could use. also i checked the spark plugs already and poured heet and octane booster in my car and let it idle for around 20 mins before posting this.
I also had EVAP issues earlier this year. Seems like they fail right around the 4-5 year mark.
Your issue that could possibly have gummed up your injectors/rail and caused those misfires may have come from bad fuel.
But it is also hard to tell as it seems like, in your write up, you had overfilled by leaving the pump on while inside the station.
Now the gas pumps should have shut off from the sensor inside the nozzle, although it may not have actually triggered due to the C43's gas tank burping air out. There is a breather line connected to the gas cap which is responsible for letting displaced air escape from the gas tank as you fill-up. This line can be clogged from particles in the fuel or dirt that has accumulated overtime -- in my opinion, this was designed extremely poorly as my car always had troubles with how you insert the nozzle since the car was brand new (perhaps German pumps are slightly different in shape or the line was undersized). Also, there are ~3 pressure relief valves in the gas tank that may be stuck or partially stuck closed that may not be allowing air to vent out into the atmosphere properly. However, this is unlikely to be the culprit as they usually stay closed and only open due to high pressurization in the gas tank during vehicle operation and not from fill-up. Another line that connects to the tank is the charcoal canister which may be blocked due to activated charcoal material breaking up into small pellets that get lodged into the line. This happens when the canister gets flooded by overfilling the gas tank and the gasoline erodes the material, breaking it down. It can affect both ends of the canister: either the input side from the gas tank or the output side which feeds into the purge valve. Finally a failing purge valve may be stuck open which creates a perpetual or overly strong vaccuum created by the engine which pulls fuel directly into the charcoal canister at an excessive rate (if flooded).
In my situation, the car was giving a CEL and struggles to start after every fill-up. I had to cut off the gasoline vapour that came in from the canister to the purge valve by manually disconnecting the valve from the engine side and blocking the raw fuel that was being pulled through on start-up/initial idle. My purge valve seemed to be functional when testing for its operation by sound when applying voltage to the solenoid and seemed to work as intended. Ultimately it was changed for peace of mind. Another component I switched out was the charcoal canister that was behind the wheel well of the rear passenger wheel. I performed a vaccuum test and it was indeed leaking ever-so-slightly inside the canister which means it could not be repaired. I sourced out a used one and installed it on the car. These changes were enough to fix the issue with start-up.
For advice, check those lines to ensure proper ventilation and be observant of the fill-up process as to not overfill or adjust nozzle so it achieves smooth flow and the car is not burping air, thus gas, out. Consider changing fuel filter if you strongly believe it is poor gas quality, although it is a whole process and quite expensive.
I also had EVAP issues earlier this year. Seems like they fail right around the 4-5 year mark.
Your issue that could possibly have gummed up your injectors/rail and caused those misfires may have come from bad fuel.
But it is also hard to tell as it seems like, in your write up, you had overfilled by leaving the pump on while inside the station.
Now the gas pumps should have shut off from the sensor inside the nozzle, although it may not have actually triggered due to the C43's gas tank burping air out. There is a breather line connected to the gas cap which is responsible for letting displaced air escape from the gas tank as you fill-up. This line can be clogged from particles in the fuel or dirt that has accumulated overtime -- in my opinion, this was designed extremely poorly as my car always had troubles with how you insert the nozzle since the car was brand new (perhaps German pumps are slightly different in shape or the line was undersized). Also, there are ~3 pressure relief valves in the gas tank that may be stuck or partially stuck closed that may not be allowing air to vent out into the atmosphere properly. However, this is unlikely to be the culprit as they usually stay closed and only open due to high pressurization in the gas tank during vehicle operation and not from fill-up. Another line that connects to the tank is the charcoal canister which may be blocked due to activated charcoal material breaking up into small pellets that get lodged into the line. This happens when the canister gets flooded by overfilling the gas tank and the gasoline erodes the material, breaking it down. It can affect both ends of the canister: either the input side from the gas tank or the output side which feeds into the purge valve. Finally a failing purge valve may be stuck open which creates a perpetual or overly strong vaccuum created by the engine which pulls fuel directly into the charcoal canister at an excessive rate (if flooded).
In my situation, the car was giving a CEL and struggles to start after every fill-up. I had to cut off the gasoline vapour that came in from the canister to the purge valve by manually disconnecting the valve from the engine side and blocking the raw fuel that was being pulled through on start-up/initial idle. My purge valve seemed to be functional when testing for its operation by sound when applying voltage to the solenoid and seemed to work as intended. Ultimately it was changed for peace of mind. Another component I switched out was the charcoal canister that was behind the wheel well of the rear passenger wheel. I performed a vaccuum test and it was indeed leaking ever-so-slightly inside the canister which means it could not be repaired. I sourced out a used one and installed it on the car. These changes were enough to fix the issue with start-up.
For advice, check those lines to ensure proper ventilation and be observant of the fill-up process as to not overfill or adjust nozzle so it achieves smooth flow and the car is not burping air, thus gas, out. Consider changing fuel filter if you strongly believe it is poor gas quality, although it is a whole process and quite expensive.
I appreciate all the info i am gonna restart my troubleshooting process with this and let you know if i find any solutions you are awesome bro.
Any update here? I'm getting a single code, P2177. When I clear it, takes a bunch of miles to come back, say 30 but does not come back on immediately. Not getting any parallel codes and performance has not suffered at all. Also very little info that I could find elsewhere of folks having the same problem.
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