[rfcoolz]

So I recently tried Shell V power for around 6 fill-ups and notice that my car idles worse than diesels (my but feels full of vibration). I switched to Sunoco, then my car idles smooth like before. BP also makes my car idles smoother. Anybody had this problem with Shell V-Power? I tried Shell in many places (PA, NJ, NY, etc.) And all of them cause roughness.

But power-wise, V-Power kicked butt with my BMS stage 1.

[whoisthis]

BP is suppose to be a good gas. Costco too.
But i don't think Sunoco is a good gas. They add something in the gas??

[jamoka3]

I use Shell gasoline, (93 octane) and have had no issues, and I feel it burns a little cleaner too. Judging from my chrome exhaust tips, the black soot is very low compared to other fuels.( I also have tried Exxon 93 octane.)
Verify that the gas attendant is indeed using 91 octane or higher with your BMS stage 1 piggyback. If you are running regular 87 octane with a piggyback it will cause the issues you listed.
Another suggestion that I have found does work is maybe running some http://m.advanceautoparts.com/mt/sho...ontent=7081073

[DrifterX]

I've been using V-Power since I got my car in March, no issues no far.

[TurboM]

Originally Posted by jamoka3

I use Shell gasoline, (93 octane) and have had no issues, and I feel it burns a little cleaner too. Judging from my chrome exhaust tips, the black soot is very low compared to other fuels.( I also have tried Exxon 93 octane.)
Verify that the gas attendant is indeed using 91 octane or higher with your BMS stage 1 piggyback. If you are running regular 87 octane with a piggyback it will cause the issues you listed.
Another suggestion that I have found does work is maybe running some http://m.advanceautoparts.com/mt/sho...ontent=7081073

Sorry man, but this is bad info. The piggyback is doing nothing at idle and the octane of the gas (i.e. 87 vs 91) with all else being equal is not going to impact the idle. The rough idle issue is related to something else, could be excess moisture or ethanol in the fuel mixture, who knows.

[jamoka3]

The octane number indicates the degree of resistance to knock. In other words, the higher the number the higher compression that will be required to fully ignite and combust the air fuel mixture in the combustion chamber. Not running the proper octane considering compression and timing will cause either premature detonation (octane level to low) hence combustion is happening before piston arrives at top dead center, or occurring to late (octane level to high) therefore unburnt fuel in combustion chamber exiting into exhaust and such. Rough idle caused by running to low of an octane?

That anyways is my interpretation of octane levels. If I am wrong pardon me and I hope to be corrected. We are all here to in fact learn!

[TurboM]

Originally Posted by jamoka3

The octane number indicates the degree of resistance to knock. In other words, the higher the number the higher compression that will be required to fully ignite and combust the air fuel mixture in the combustion chamber. Not running the proper octane considering compression and timing will cause either premature detonation (octane level to low) hence combustion is happening before piston arrives at top dead center, or occurring to late (octane level to high) therefore unburnt fuel in combustion chamber exiting into exhaust and such. Rough idle caused by running to low of an octane?

That anyways is my interpretation of octane levels. If I am wrong pardon me and I hope to be corrected. We are all here to in fact learn!

Thats correct, but the cylinder pressures are very low at idle. 4pts in octane will not be the cause of a rough idle in this scenario. We're not talking about a 16:1 compression race motor here.

[rfcoolz]

I mostly filled up by myself with V-Power since I lived in Philly and there's no attendant. I just suspect either the new nitro thing or the high ethanol content since I felt a great power boost from them. I just filled up with full tank of V-power somewhere in Jackson, NJ and my car started to idle pretty rough again. Maybe I'll try techron just in case its idling rough because of sunoco.

[rfcoolz]

Or is it also possible that Shell cleans up the system really well that it pushes out all the junk all over the place? Sounds like a bad logic though

[mge92]

It could just be a badly maintained gas station with excess water in the fuel.

[rfcoolz]

Originally Posted by mge92

It could just be a badly maintained gas station with excess water in the fuel.

But it happened at all different Shell station in different states that I filled up.

[mge92]

Try the Italian Tune up. Put the car into manual and keep the car at around 4000 rpm for 10 mins and see if that helps. Also driving your car like you stole it might help haha.

[rfcoolz]

I always drive my car like I just robbed a bank lol. 130 MPH from Philly to Six Flags in Jackson,NJ.

[FSociety]

Funny once I used 89 when there was No 93 available (Sandy Storm) and noticed it idle rough, put 93 back and it went away.
Shell is the best premium gas in the NorthEast (Power and Burns Cleaner)
Definitely put a bottle of Techron or Redline when the tank is almost empty to see.

[Mike@N54Tuning.com]

Originally Posted by ROBNYC

Funny once I used 89 when there was 93 available and noticed it idle rough, put 93 back and it went away.
Shell is the best premium gas in the NorthEast (Power and Burns Cleaner)
Definitely put a bottle of Techron or Redline when the tank is almost empty to see.

+1

Shell is pretty good gas so its pretty odd to have issues with it across many different stations.

Mike

[rfcoolz]

Maybe there's something wrong with east coast Shell? I never filled up with anything lower than 93 (never touched 91) Every shell yields the same bad result, while every BP and Sunoco removes the problem. I've bought 20 oz Techron and will see if it helps and update.
Every one said that Shell is one of the best gas and always get a very good results. I'm dieing to figure out what's wrong with my car.

[rfcoolz]

Originally Posted by ROBNYC

Funny once I used 89 when there was No 93 available (Sandy Storm) and noticed it idle rough, put 93 back and it went away.
Shell is the best premium gas in the NorthEast (Power and Burns Cleaner)
Definitely put a bottle of Techron or Redline when the tank is almost empty to see.

By the way, do you recommend Techron or Redline?

[FSociety]

Originally Posted by rfcoolz

By the way, do you recommend Techron or Redline?

Redline, Techron in that order

But get whichever of those u can from your local Auto store.

Weird because I used Costco, BP, 76Gas, ExxonMobil, Shell and Valero.
Did some testing in BMW 328xi, Mercedes C300, Cadillac STS, and now X3 and notice Shell is best performance and better mpg.

Shell
Valero
76Gas
Costco
BP
ExxonMobil

In that order works for me, and have not tried Sunoco only did once in my Cadillac but can't remember and will not put it in my current car.

[rfcoolz]

Originally Posted by ROBNYC

Redline, Techron in that order

But get whichever of those u can from your local Auto store.

Weird because I used Costco, BP, 76Gas, ExxonMobil, Shell and Valero.
Did some testing in BMW 328xi, Mercedes C300, Cadillac STS, and now X3 and notice Shell is best performance and better mpg.

Shell
Valero
76Gas
Costco
BP
ExxonMobil

In that order works for me, and have not tried Sunoco only did once in my Cadillac but can't remember and will not put it in my current car.

That's strange, because Sunoco gives me way better MPG than Shell. Sunoco: 23 City Shell: 17 City. Downtown Philadelphia with medium traffic is my most common driving condition. I'll try and order some redline too then.

[rfcoolz]

Originally Posted by ROBNYC

Redline, Techron in that order

But get whichever of those u can from your local Auto store.

Weird because I used Costco, BP, 76Gas, ExxonMobil, Shell and Valero.
Did some testing in BMW 328xi, Mercedes C300, Cadillac STS, and now X3 and notice Shell is best performance and better mpg.

Shell
Valero
76Gas
Costco
BP
ExxonMobil

In that order works for me, and have not tried Sunoco only did once in my Cadillac but can't remember and will not put it in my current car.

Do you know if every shell station in the US contain Nitro+? Maybe it's because yours have no Nitro while mine have it. My college friend's F80 also idles rough with Philly's V-Power compared to BP.

[Tomahawk]

I just tried the Nitro+. Have consistently used the old v-power 93 and it was good. The Nitro+ gave me 10% LOWER gas mileage. Car seemed to run fine but the mileage difference is unacceptable. Luckily i have a station on the way to work that has 100% gas. Only 91 oct but car loves it! On the old v-power 93 I would avg 29.7 combined. The nitro+ had me working to avg 27. The 91 no ethanol I'm at 32.9 avg COMBINED.

Am I the only one the laughed at the comment about a gas station attendant? I haven't seen that since 1991.

[rfcoolz]

I wish there's 100% gas station near me. I tried techron and it helped a little bit for the rough idle, but not that significant. I just suspect the 10% "foreign" stuff in V-Power that causes the rough idling.