Hello everyone.

Before I get yelled at, please know I've researched this soot issue (even on here) and appears to be "normal" for the most part. However, here's my question .. If you notice it more with one brand of gas vs. the other, would it be wise to stop using the gas you're seeing it more with?

I remember this concerned me a while back, as I had "some" showing up. Yesterday, I noticed it really black for the first time. Note the following, if this makes any sense.

1. Started fueling with Shell V Power 93 and was getting some soot, not much
2. Switched to BP 93 for a few tank-fills and noticed no soot at all
3. Car was recently serviced, Service Dept. topped off the tank (brand/octane unknown). At about 1/4 tank I filled up with Sunoco 91 and added a bottle of Techron. Last night after running all round town I notice much soot (charcoal black) on the tailpipe.

I'll keep an eye on this, but thought I'd post my findings so far.

Regards,
David

Sent from my iPad Air using NAMotoring

 

You had my attention until #3 where fuel additive was put into the mix with the third brand of fuel and then soot was noted. BTW what work was performed by the dealer. Any updates to the DME ?

 

My question would be why use different brands in the first place? There was a time when I did this while traveling, which I'm on Vacation now and 1,500 miles from home, when I did use another brand (Chevron/Velaro) but only because I didn't think I could find my brand (Shell) at my usual fuel stops. I researched shell.com and was able to locate stations along my route and at comfortable distances. My only problem while on Vacation I don't have the option of 93 octane anymore, in CA and AZ 91 is the best I can get.

I do have one question, along my route home, I did find an Ethanol Free Station that I would be able to fuel at if I so choose, my question is...how "empty" does Molly have to be? That could potentially be my first fuel stop, but I don't want to take chances if she needs to be on fumes before I fuel.

TIA

 

RJKimbell,

i use E0 whenever possible, getting ~3-4 more MPG in town and ~5-6 better MPG on a full tank all freeway run (even if the E0 is 91 octane, i get better MPG than E10 93 octane)

i do not worry about mixing E0 with E10, i almost never pass up a station with E0 (they are few and T00 far apart)

using E0, the engine runs smoother on a cold start, particularly a sub-freezing cold start

have you looked at the website http://pure-gas.org/index.jsp ? they have a mobile app also

E10 IS EVIL!

 

Two things I find that work well to mitigate carbon buildup on the beer cans.
Barkeepers Friend to clean them and an occasional Italian Tune Up to blow the cobs out of the stack.

 

Wd-40 on a rag is great too if the carbon/soot is not too old...
You will notice many cars have non-chromed tailpipes.....
Think there is a reason it.....soot blends in with rust/dirty stainless steel....

As for why there is more with some brands...guessing it has more to do with driving style, length of drives, etc....techron is good stuff, but it is basicly a light petroleum distillate (like diesel fuel or lighter fluid) with the detergent suspended in it....Better brands have more/better detergents...cheaper can sometimes be mostly distillate.....

 

...ooops! Forgot. A can of BG44K every 6 months or just before a long road trip. Probably has nothing to do one way or the other with tail pipe soot but it puts a smile on your MINI while your MINI puts a smile on you.

 

i see soot as being a little left over fun!

its on both my bikes and my mini!

 

Hello gRay.

Here's the repair that was done. The only reason I switched gas merchants is because Sunoco carries the 91 octane my manual calls for so I thought I'd give it a try. Since they're not listed as "TopTier" I thought I'd add a bottle of Techron as a safety measure.



Hope this helps.

Thanks for your time.
David

 

Thank you for the App. Info. didn't realize there was one available for Android. I will use that on my trip home!! 👍

 

Hi MINIacts,

So I'm thinking the soot buildup may have happened when the dealer had the car for three days and may have been running it idle to check for leaks?

So far, two days of heavy driving/motoring and no "new" soot.

How long does it take for that stuff to buildup anyway? :(

Regards,
David

 

Couple or three weeks and they start looking a little frowzy and get a quick wipe down.

 

When I windex my windows I windex the tail pipe soot.

 

I noticed some soot today and wiped it off with a napkin and some WD-40. Worked really well. It's odd because it almost looks muddy-like and sorta oozing down the tailpipe. I'm attaching a picture of it below.

One question can the type of gas (octane, brand, etc.) make a difference on this soot phenomenon? It's odd because when I was using Shell V-Power 93, I saw a little of it. When I switched to BP 93 I saw none, and when the SC had my car for three days and topped it off (fuel unknown) I saw a lot. I let the gas tank get to half, then I topped it off with Sunoco 91 Octane and at a half-a-tank, this is what I see. Not sure if that's the residue of the gas the SC used, a mixture of both or what. I'm almost tempted to let it run almost to empty (something I try not to do with any of my cars) then fill up with BP again to see what happens.

Thoughts anyone?

Regards,
David

Sent from my iPad Air using NAMotoring

 

Moisture is a byproduct of combustion....
That is WHY exhausts rust....and largely the reason why Stainless Steel has become the main metal of choice in recent years...so it looks a bit muddy cause the soot mixes with moisture...and can get blown back/out.....
Seasonally, you may see water dripping out...Bio-fuels, like E-10 (the most common blend in the US), etc, make MORE moisture when burnt.

 

A lot of the water in the tailpipe is from condensation and is perfectly normal.

And ethanol blended fuels is great for making power.

 

Thanks Zippy.

I've seen water on occasion which is no big deal. However, could the gas brand/octane level actually play a role on just how much black soot is introduced into the condensation equation?

Regards,
David

 

Thank you Ceren.

See question I asked Zippy above.

Regards,
David

 

Higher octane tends to have more ethanol.... It is used as a agent to increase the octane when blended...
So the 91 and 93 you buy might be the same "base" stock...but the 93 might have 10% ethanol blended at the fuel terminal, and the 91 might have a few % less....

 

And this translates to more/less soot? Not sure where ethanol is coming to okay here.

Regards,
David

Sent from my iPad Air using NAMotoring

 

I have a customer who changes his oil every 5 k since he bought it and uses BG44K on every oil change and he nevers has soot on the tail pipes.Also inspected his intake valves and found no carbon which is really something for a R56 Cooper S hard top with 78,000 miles on it.

Erik

Ferneys Lube and Auto Repair

 

I guess I'm going to assume the gas merchant and/or octane has nothing to do with soot or how much (if any) soot is seen.

Regards,
David

 

WARNING: Thread Hijack
Are you kidding or are you being facetious? It takes more energy to produce ethanol that the ethanol can generate plus it takes HUGE amounts of water to produce. Ethanol, overall, is a negative energy product and a governmental boondoggle none of which take into account what it can do to engine components that aren't designed for it along with the added cost to automobiles to be made ethanol proof.

"...and they're turning FOOD into FUEL!!!" Lewis Black
If you haven't gathered by now, I am an ethanol disputant.

 

I'm a little uneducated with additives. What is BG44K? We're about to move from Nebraska to South Carolina, so a road trip is coming soon. Next week, new tires and a brake job and oil change...:>)

 

I also use Shell V-Power 93 and have never seen this on my tailpipe. I agree with ZippyNH's assessment regarding moisture but I will also add this observation. My Roadster is garage kept all the time and the probably the main reason I never see a drip mark. If your MINI is kept outside, perhaps the heating and subsequent cooling of the tailpipe metal is creating moisture on the tailpipe. Once that moisture builds on the surface, it drips and out the tailpipe. Just a thought.