Bad fuel = misfiring code P030285 - now solved
#1
Senior Member
Thread Starter
Bad fuel = misfiring code P030285 - now solved
A long story with a happy ending…
Living near the Gulf of Mexico we are always on alert when there is a tropical storm or hurricane that is about to enter the Gulf Coast, the precautions that I take in advance is to fill up the tanks on all of the cars and load up some extra (5x5 gls) containers of fuel so we can escape if needed in time if the storm/hurricane starts heading into our direction (comes within a 20-30 miles radius).
So, when the last storm “IDA” came into the Gulf during the last week of August, 2021 I checked my standby fuel reserve, noticed that I had 2x5 glns left from a previous alert and added 3x5 glns just in case.
Anyway, we were lucky this time around as the storm passed us by about 70 mile from the coast and headed for East Texas which is about 300 miles north from where we are located.
During the time that it looked like IDA could come our way I had parked the GTS and drove in my S65.
So it was not until September the 13th that I got back into the GTS and found that all of a sudden she was not running very smoothly and getting worse in the next 2-3 days, on top that I was getting a CEL come on when I stepped hard on the gas.
Next thing I did was to run Xentry and found out that I had a misfiring condition (code P030285) on the #2 cylinder. I erased them 2-3 times and test drove it again, after the 3 time I decided to change out the paired #1&2 coil pack (which is quite a B-itch job - completed this on September 21.2021) test driving it again it first looked good but then after hard acceleration the CEL came back.
At this point I thought I might have a bad spark plug or injector in the #2 cylinder however with an engine in the car that has only about 16k miles on it was kind of hard to believe.
After all this I became to question myself on how or why I would suddenly have this issue and I than remembered that in order to top of the fuel tank of the GTS I had emptied 2x5 glns with the gasoline that had been sitting around for 4-6 month in my garage into the tank and not used the fresh 3x5 gallons I had bought.
Well today with the fuel tank level down to 1/3 I decided to add a 12 fld/oz Techron injector cleaner to the tank & added 12 gallon of fresh pumped fuel and did an “Italian” tune-up, the end results are that I no longer have the CEL light come on and the car pulls strong in all available drive modes, she idles smooth and steady without any burps.
So, for those that don’t drive their cars very regular beware these cars are very sensitive to having fresh/clean fuel and if they sit around you may have to take precautions to avoid fouled injectors!
Happy motoring to all.
Best H
Living near the Gulf of Mexico we are always on alert when there is a tropical storm or hurricane that is about to enter the Gulf Coast, the precautions that I take in advance is to fill up the tanks on all of the cars and load up some extra (5x5 gls) containers of fuel so we can escape if needed in time if the storm/hurricane starts heading into our direction (comes within a 20-30 miles radius).
So, when the last storm “IDA” came into the Gulf during the last week of August, 2021 I checked my standby fuel reserve, noticed that I had 2x5 glns left from a previous alert and added 3x5 glns just in case.
Anyway, we were lucky this time around as the storm passed us by about 70 mile from the coast and headed for East Texas which is about 300 miles north from where we are located.
During the time that it looked like IDA could come our way I had parked the GTS and drove in my S65.
So it was not until September the 13th that I got back into the GTS and found that all of a sudden she was not running very smoothly and getting worse in the next 2-3 days, on top that I was getting a CEL come on when I stepped hard on the gas.
Next thing I did was to run Xentry and found out that I had a misfiring condition (code P030285) on the #2 cylinder. I erased them 2-3 times and test drove it again, after the 3 time I decided to change out the paired #1&2 coil pack (which is quite a B-itch job - completed this on September 21.2021) test driving it again it first looked good but then after hard acceleration the CEL came back.
At this point I thought I might have a bad spark plug or injector in the #2 cylinder however with an engine in the car that has only about 16k miles on it was kind of hard to believe.
After all this I became to question myself on how or why I would suddenly have this issue and I than remembered that in order to top of the fuel tank of the GTS I had emptied 2x5 glns with the gasoline that had been sitting around for 4-6 month in my garage into the tank and not used the fresh 3x5 gallons I had bought.
Well today with the fuel tank level down to 1/3 I decided to add a 12 fld/oz Techron injector cleaner to the tank & added 12 gallon of fresh pumped fuel and did an “Italian” tune-up, the end results are that I no longer have the CEL light come on and the car pulls strong in all available drive modes, she idles smooth and steady without any burps.
So, for those that don’t drive their cars very regular beware these cars are very sensitive to having fresh/clean fuel and if they sit around you may have to take precautions to avoid fouled injectors!
Happy motoring to all.
Best H
#2
Member
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I left my BMW (now Jeep) and boat down in Florida for 6 months in the summer. One runs 92 the other regular ethanol-free. I fill both tanks up before I leave. Never had this problem. I would keep the tank full to keep the condensation down, don't store gas longer the 6 months and maybe buy your gas somewhere else. Glad you got it fixed.
Last edited by gle43FL; 09-25-2021 at 07:04 AM.