Second opinion] Sure why not

Second opinion] Sure why not Mechanic's Assistant: What is the make/model/year of your car? 2015 Smart Fortwo Mechanic's Assistant: Are you fixing your vehicle yourself? What have you tried so far? I tried taking...

Second opinion] Sure why not Mechanic's Assistant: What is the make/model/year of your car? 2015 Smart Fortwo Mechanic's Assistant: Are you fixing your vehicle yourself? What have you tried so far? I tried taking it to Mercedes and 400 bucks later still have the same problem Mechanic's Assistant: Anything else you want the Mechanic to know before I connect you? Check engine light and loss of power if I stop, turn the car off and then restart it runs fine but the check engine stays on

Let’s see if something else has a better ideaI ordered the BG fuel cleaner
Automotive Expert
Good evening, my name is \*\*\*\*\* \*\*\*\*\* ill be helping you, so sorry to hear about the issues here on the Smart. Now what codes was the dealer able to pull up when it came in?

All the service advisor said was old misfire on all three cylinders
Automotive Expert
okay thank you, \*\*\*\*\* \*\*\*\*\* was done at the dealer?

Replaced all three [spark plugs](/topics-spark-plug-mercedes/)
Automotive Expert
and that was it?

Got recommended to run BG fuel cleaner. Thoughts?Yep 400 buck for three plugsCheck engine light came back the next day
Automotive Expert
if we are still misfiring after the new plugs it does sound like itll be fuel related to me, the fuel cleaner is a good idea but i do not think itll solve your issue. i would recommend we get fuel pressure tested to ensure the pump is healthy and working correctly and after that also look into the position sensors and ensure they are reading correctly. the fact that its intermittent makes it harder to narrow buts that where i would start.

What would normal foul presume be and do you think a normal Mech can perform or should I go back to MercedesSorry normal fuel pressure be?
Automotive Expert
i would try and find a local automotive shop that has experience with Mercedes if we can, if not itll need to be the dealer

Ok thanks I just hate wasting money on the dealer when they are guessing instead of being the experts. The service advisor told me that the plugs should be replaced every three years no matter the millage and that just did not make sense. If it was carbon why would restarting let the car run as normal? Intermittent issues are the worstThanks for thinking about it
Automotive Expert
correct, the fact that its intermittent makes me suspect an electronics issue or fuel in that order. this is why independent shops are better since they dont have the luxury of guessing. im glad to have helped!

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