Problem w/ Petro Can Gas

[trdjce10]

I have a 05 WRX with Cobb Stage 2. I have been running ESSO gas 99% of the time and once with Shell and 711. No problem with those three and car ran great.

But tonight I filled with Petro Can (ESSO or Shell was too far). Put in $20 worth. Drove for like 20 secs, the car "jerked", then again 20 secs later, then again 20 secs later. It almost seemed like it was misfiring, but no engine light. I wasn't going fast and I wasn't on boost.

My car just roll over the 20000 KM mark. Had to Cobb tune for over 10000 KM. Never had a problem until tonight.

Anyone had that problem?

I'm going back out tonight and will see what happen.

[googe]

do you know what knocking sounds like? if not, listen for what sounds like BBs firing in a coffee can, a pinging sound. if you hear that, youll want to pour some toluene in or something.

kind of weird if you werent on boost, it could be running too rich actually. maybe the cobb unit is dumping too much fuel early?

[pitwipe]

Maybe use the Stage 1 or stock real-time map until you can empty the tank and put in the ESSO again. :dunno:

[cosmok]

What octane did you put in and was your tank right empty when you fueled at Petro?

[mac_82]

what octane and what rpm did this happen at?

[~Leah~]

Someone told me that Petro's winter gas fucks with the octane %age ... so you pay for premium but you're not really getting it cuz of the shit they put in?

[Foz]

I've never filled with Petro. Always Esso or Husky then Shell.

[trdjce10]

I didn't hear any knock...

Anyway I just came back after a 30 min. drive, and it seems normal now. But I didn't go on boost much due to the road condition.

I filled with 91 oct and RPM range probably between 2 - 3k when it happened...3 times total. At first, I thought it was me, but not 3 times in a roll.

It wasn't empty...gas light was not on yet.

I don't know, its just weird that it happened right after Petro Can fill. :confused:

[mac_82]

Hmmm after doing some research I am now thinking about switching off Petro Canada gasoline.... I have used it in my car for 6 months with no problems, but it seems they have the crappiest premium gas out there.

[Foz]

Probably that crappy Wintergas additive that PetroCan puts in their gas.

http://www.petrocan.com/eng/prodserv/fuels/10537.htm

[GQBalla]

hehehe i always use esso!

[pitwipe]

^ Yep, I always use ESSO too, and use my ESSO points for the car-wash.

[zain123]

husky isnt too bad.. their 94 octane is :thumbsup:

[JAYMEZ]

I always use Oct 94 :thumbsup:

[TeamBestBud]

petro gas is :bullshit:

[bspot]

:rolleyes:

All gas is the exact same, out of the exact same refinery. The additives are different, but they don't make octane go away. It is possible your cars sensors are fooled by the additive, but come summertime its all the same shit.

[cosmok]

Originally posted by bspot
:rolleyes:

All gas is the exact same, out of the exact same refinery. The additives are different, but they don't make octane go away. It is possible your cars sensors are fooled by the additive, but come summertime its all the same shit.

Yes and no. If you put in more long chained molocules (ie, "gas line antifreeze") that don`t help with fuel economy or power production , they are taking up volume in the litre of fuel that would have other wise been a hydrocarbon (less products that actually give you power and economy).

[RickDaTuner]

Originally posted by trdjce10
I have a 05 WRX with Cobb Stage 2. I have been running ESSO gas 99% of the time and once with Shell and 711. No problem with those three and car ran great.

But tonight I filled with Petro Can (ESSO or Shell was too far). Put in $20 worth. Drove for like 20 secs, the car "jerked", then again 20 secs later, then again 20 secs later. It almost seemed like it was misfiring, but no engine light. I wasn't going fast and I wasn't on boost.

My car just roll over the 20000 KM mark. Had to Cobb tune for over 10000 KM. Never had a problem until tonight.

Anyone had that problem?

I'm going back out tonight and will see what happen.

what you felt was your ECU seeking the Knock point.
Esso gasoline has a Higher BTU concentration, compared to the ethanol Blended Petro Canada gasoline, wich means that the Esso gas will give you more miles per smile but will do so at the cost of having a lower tollerance to knock, Petro canda gas on th other hand has lower BTU per volume and because of the methonal content is more resistent to knock even when its rated at 91 you can also say that Due to the additives in the petro Canada gas you usually get a higher octane rating than 91, hence you ecu notices right away that there is no knock where there used to be when you were on the esso gasoline, so it's trying to relearn the fuel curve for the higher octane gas.

when you go from Petro gas to Esso gas the same thing will happen, and its even more amplified when you go from Esso gas to Husky 94, believe it or not but the best gas I have ever run through my car is a mix of 20L esso 91 and 20L Husky 94, that combo has given me the best fuel economy and best bang for the buck. short of VP 103

Subaru ECUs' are super responsive and hella intelligent but the short wind of it all is that, your ecu is just recalibrating for the new fuel.

But boost cut and a full timing retard will happen in these colder days when you are running a Cat-less exhaust and some sort of piggy back EM due to the inefficient Turbo waste port design :thumbsup:

[rony_espana]

Originally posted by RickDaTuner


what you felt was your ECU seeking the Knock point.
Esso gasoline has a Higher BTU concentration, compared to the ethanol Blended Petro Canada gasoline, Due to the additives in the petro Canada gas you usually get a higher octane rating than 91, hence you ecu notices right away that there is no knock where there used to be when you were on the esso gasoline, so it's trying to relearn the fuel curve for the higher octane gas.

when you go from Petro gas to Esso gas the same thing will happen, and its even more amplified when you go from Esso gas to Husky 94, believe it or not but the best gas I have ever run through my car is a mix of 20L esso 91 and 20L Husky 94, that combo has given me the best fuel economy and best bang for the buck. short of VP 103

Subaru ECUs' are super responsive and hella intelligent but the short wind of it all is that, your ecu is just recalibrating for the new fuel.

But boost cut and a full timing retard will happen in these colder days when you are running a Cat-less exhaust and some sort of piggy back EM due to the in efficient Turbo waste port design :thumbsup:


http://i37.photobucket.com/albums/e85/rony_espana/alizadeh_einstein.gif

[trdjce10]

RickDaTuner:

Thanks for the great info.

[mac_82]

So Rick you are saying for a turbo Subaru (wrx / STi):

Esso 91 < Petro Can 91 < Husky 94

??

Should I keep my faith in Petro 91, or try to switch to Esso 91 or Husky 94 (not sure where the nearest Husky market is in Edmonton).

[RickDaTuner]

Originally posted by mac_82
So Rick you are saying for a turbo Subaru (wrx / STi):

Esso 91 &lt; Petro Can 91 &lt; Husky 94

??

Should I keep my faith in Petro 91, or try to switch to Esso 91 or Husky 94 (not sure where the nearest Husky market is in Edmonton).

actually its more like< Shell 91 < Esso 91 < Husky 94 < Petro 91

the Only reason that the "pure 91" based gasolines feel like worse at times is because they are a True 91 AKI Octane, but in the end they are more predictable, more stable, and just in general have a Higher BTU per Volume content, Husky 94 allows you to make the power, but at the cost of extended Fuel consumption, if and when Esso and Shell make their non additive based 94 octane, it will surely knock the socks of the 94 ethanol blend

all 91 and above fuels are safe to run through the Impreza its the lower grades that will really cause the damage.

[googe]

on an sti, 94 will be better for power but way worse in fuel consumption. a wrx will likely not make a difference as its ecu isnt aggressive enough to optimize itself for 93 afaik.

[D. Dub]

I have a Daimler Chrysler 5.9 litre in my Jeep and its really sensitive to octane. The Petro Can works great in this engine.

Another possibility is that maybe the OP just got a tank of bad gas or "wet gas" :dunno:

[trdjce10]

Yeah, that Petro 91 gas just feels different.

I guess as long as it is 91 octane it should be safe.

Again, thank you for great info.