[vasillalov]

Folks,

This weekend I took my GF for a weekend trip away from the city. On the way back, I was running really low on fuel and we were in the middle of nowhere. So I pulled over at the first Shell station I could find since I always get Shell gasolene.

To my surprise the fuel station ONLY had migrade 89 octane gasolene. On the pump, they had a hand written sign that the cost of 89 octane is the same as regular. I would not be surprised if they only had regular fuel (87 octane) and they sold it as midgrade to the unsuspecting customers...

Anyway, I filled the fuel tank with whatever magic juice came out of the pump and moved on. I figured that since I am on the highway and I will be cruising for 90% of the time, the engine will just burn the fuel and there won't be too much of an issue since the engine won't be under boost.

...a little background info:
My car is completely stock with the exception of full catless turbo back exhaust system which was installed way back in April of this year by a local highly reputable race shop. Also, I've installed the BMS O2 Similator almost an entire month prior to that.

Since April, I've put close to 5000 miles on the car with zero issues. I've taken several long trips like that.

Now fast forward to Sunday... This is the first time that I've ever had to put crap fuel in the car. About 50 miles after fueling with 89 octane shell, I get half check-engine light while I did a short burst of romping on the gas pedal to 110 mph.

29F4:
29F4 Catalytic converter conversion
Error will cause a warning light
Error is not currently present
Test conditions have been completed
Short circuit or signal interruption

Freeze Frame Information
Event 1Odometer 27192kms 16896miles
Engine speed 2,656.00 rpm
air mass calculated 238.74 mg/stk
Engine temperature 95.25 °C
Intake air temperature 14.25 °C



29F5:
29F5 Catalytic converter conversion 2
Error will cause a warning light
Error is not currently present
Test conditions have been completed

Freeze Frame Information
Event 1Odometer 27192kms 16896miles
Engine speed 2,656.00 rpm
air mass calculated 238.74 mg/stk
Engine temperature 95.25 °C
Intake air temperature 14.25 °C


The car was fine. No limp mode or anything like that.

The point that I am trying to make here is that if you are running BMS O2 simulator and you start getting CEL regarding the catalytic converter AFTER you've driven CEL free for a while, chances are that the fuel you last purchased is not up to par. A lot of people scream because they think that BMS O2 Sim is not installed correctly or because it is not dialed to the correct setting. I believe that low-octane fuel could be the culprit for some of these problems!

Discuss...

[bulldog_yyc]

Originally Posted by vasillalov

Folks,

This weekend I took my GF for a weekend trip away from the city. On the way back, I was running really low on fuel and we were in the middle of nowhere. So I pulled over at the first Shell station I could find since I always get Shell gasolene.

To my surprise the fuel station ONLY had migrade 89 octane gasolene. On the pump, they had a hand written sign that the cost of 89 octane is the same as regular. I would not be surprised if they only had regular fuel (87 octane) and they sold it as midgrade to the unsuspecting customers...

Anyway, I filled the fuel tank with whatever magic juice came out of the pump and moved on. I figured that since I am on the highway and I will be cruising for 90% of the time, the engine will just burn the fuel and there won't be too much of an issue since the engine won't be under boost.

...a little background info:
My car is completely stock with the exception of full catless turbo back exhaust system which was installed way back in April of this year by a local highly reputable race shop. Also, I've installed the BMS O2 Similator almost an entire month prior to that.

Since April, I've put close to 5000 miles on the car with zero issues. I've taken several long trips like that.

Now fast forward to Sunday... This is the first time that I've ever had to put crap fuel in the car. About 50 miles after fueling with 89 octane shell, I get half check-engine light while I did a short burst of romping on the gas pedal to 110 mph.

29F4:
29F4 Catalytic converter conversion
Error will cause a warning light
Error is not currently present
Test conditions have been completed
Short circuit or signal interruption

Freeze Frame Information
Event 1Odometer 27192kms 16896miles
Engine speed 2,656.00 rpm
air mass calculated 238.74 mg/stk
Engine temperature 95.25 °C
Intake air temperature 14.25 °C



29F5:
29F5 Catalytic converter conversion 2
Error will cause a warning light
Error is not currently present
Test conditions have been completed

Freeze Frame Information
Event 1Odometer 27192kms 16896miles
Engine speed 2,656.00 rpm
air mass calculated 238.74 mg/stk
Engine temperature 95.25 °C
Intake air temperature 14.25 °C


The car was fine. No limp mode or anything like that.

The point that I am trying to make here is that if you are running BMS O2 simulator and you start getting CEL regarding the catalytic converter AFTER you've driven CEL free for a while, chances are that the fuel you last purchased is not up to par. A lot of people scream because they think that BMS O2 Sim is not installed correctly or because it is not dialed to the correct setting. I believe that low-octane fuel could be the culprit for some of these problems!

Discuss...

agree 100%; received a similar issue when I filled up at Costco (with 91 though). Shell 91 or Sunoco 94 don't give me any trouble.

[mase]

Interesting... I just got the code after running some BG 44k in my tank for a little while, with 91 octane..

[vasillalov]

Hmmm, I wonder if this is a way to find good fuels...

[lyndon_h]

Originally Posted by vasillalov

Hmmm, I wonder if this is a way to find good fuels...

A better way would be to run a Procede and see what it autotunes for the gas. I couldn't help it, vasillalov.

[ttbmer]

Originally Posted by vasillalov

Hmmm, I wonder if this is a way to find good fuels...

Don't think so. I'm running AR DPs and AMS Full CBE on 100 oct (rebel gas station) and still getting those codes. I do need to take the time to play more with the DP fix. Is set at 6 like the instal guide recommends

[mwahlert]

romping on the car at all while running 89 octane fuel is not a smart idea to begin with.

[bulldog_yyc]

Originally Posted by ttbmer

Don't think so. I'm running AR DPs and AMS Full CBE on 100 oct (rebel gas station) and still getting those codes. I do need to take the time to play more with the DP fix. Is set at 6 like the instal guide recommends

takes a bit of time and varies from car to car (due to ECU software) but you should be able to get it dialed in if you follow the directions from the guide

[vasillalov]

Originally Posted by lyndon_h

A better way would be to run a Procede and see what it autotunes for the gas. I couldn't help it, vasillalov.

Sure sure! For as long as that makes you laugh..