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black spots/marks, of soot/oil residue on back of car?

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hi peeps, my car is clean (for once) and I've been really stretching its legs today, and there are black sooty marks on the rear, the as if you drove through some light muddy water on a hot dry road (it has happened before, and this is what I thought they were) but I know now its been dry since I cleaned it, and they have just appeared after a big blast...

anyone else experianced this? anyone suggest a reason?

I seriously doubt its oil, the engine bay is as clean as when it was new, was serviced at 10k and is now 12.5k and I haven't hat to top up oil in that 2.5k.... plus they wipe/clean off real easy

when I wiped one off with a finger, it seemed sooty. maybe residue from the little black cloud you get when booting it?

thanks.

shouldnt get a black cloud when booting it on a petrol

I get a little bit of a black cloud on my petrol octavia vrs. Just running abit rich which i would expect it to do because its been remaped and therefore more boost + more air and fuel

  • Author

shouldnt get a black cloud when booting it on a petrol

I get a little bit of a black cloud on my petrol octavia vrs. Just running abit rich which i would expect it to do because its been remaped and therefore more boost + more air and fuel

yeah, there was a thread about it, most of them do give a little puff of black smoke (its not a black cloud like a diesel "boot it", just a little puff, just visible IF you are watching for it, I never noticed until I read the thread about it, then watched mine!) .. especially if you have been really pottering, then give it a massive bootfull! Simons evoX used to do the same too... so I'm not worried about it.. there are no symptoms, the car is running fine, maybe I am going through something on my way home, but my "chrome" tailpipes are certainly NOT chrome! lol...

edit to OP, and they are not a film of soot, such as on a mark I , just a few irregulare shaped blotches, a few mill wide...

It's what turbo'd cars do.

yeah, there was a thread about it, most of them do give a little puff of black smoke (its not a black cloud like a diesel "boot it", just a little puff, just visible IF you are watching for it, I never noticed until I read the thread about it, then watched mine!) .. especially if you have been really pottering, then give it a massive bootfull! Simons evoX used to do the same too... so I'm not worried about it.. there are no symptoms, the car is running fine, maybe I am going through something on my way home, but my "chrome" tailpipes are certainly NOT chrome! lol...

edit to OP, and they are not a film of soot, such as on a mark I , just a few irregulare shaped blotches, a few mill wide...

I also get these little black spots on mine if I give it the beans. I haven't noticed it recently though, they only seemed to appear for the first 5,000ish miles of the cars life and I haven't seen them again (im now at 8,000 miles). My chrome tailpipes are also completely black!

-Will :)

I havent noticed it on mine. what colour is your car? (Mine is Blue, so not easy to see dark patches)

I have just driven though the lake district at speed, and noticed lots of black dots on the front of my car though... :giggle:

I too get some black puffs when i give it some beans and it's quite normal for a turbo-car to react that way x).

  • Author

I also get these little black spots on mine if I give it the beans. I haven't noticed it recently though, they only seemed to appear for the first 5,000ish miles of the cars life and I haven't seen them again (im now at 8,000 miles). My chrome tailpipes are also completely black!

-Will :)

I too get some black puffs when i give it some beans and it's quite normal for a turbo-car to react that way x).

all good to hear :thumbup:

I havent noticed it on mine. what colour is your car? (Mine is Blue, so not easy to see dark patches)

I have just driven though the lake district at speed, and noticed lots of black dots on the front of my car though... :giggle:

rallye green (white wheels) and yes you will pick up about a kilo of insects if you drive around all day this time of year! lol...

Havn't noticed it on mine, only done 600 odd miles though. Have heard a rumour that differing fuel types will make it burn and smoke a bit more if its not the same as usual if that makes sense?!

  • Author

Havn't noticed it on mine, only done 600 odd miles though. Have heard a rumour that differing fuel types will make it burn and smoke a bit more if its not the same as usual if that makes sense?!

I'm always either BP ultimate or shell V-Power... mostly ultimate. I only put 95 in if I get caught out!

Could be the transition between BP and Shell. My master tech seemed to think they ran rich anyway and it was fairly normal.

  • 3 weeks later...

Just been to Pickering and back ( 100miles each way) noticed the same black tar/ soot all over the back of the car and chrome exhausts are blacker than a very black thing.

looks more like an oily substance than soot

I'm always either BP ultimate or shell V-Power... mostly ultimate. I only put 95 in if I get caught out!

Almost ran out of fuel on the track day friday, put £10 of BP ultimate (97ron) and the car did not like it, was very hesitant. Luckiky it was only about 6litres which was enough to feet me to a she'll garage

i only ever use 97ron super from sainsburys ive never noticed any issues the myths seem to think its the same as bp ultimate

ive read cases of carbon building up an sooty fumes and wondered if 99ron is too much for the car too burn properly

Edited by daydotz

Only vpower 99 in my baby. Tried excellium which is 97 and car felt gutless in low revs.

Found a garage near me selling 102 octane fuel but its 2.50 a litre and the people in the garage try telling you it'll blow road cars up. Only for use in race cars apparently haha.

For that price it would be cheaper to use vpower and add some extra octane.

I've noticed this on mine as well. Like a black soot that covers the boot. If you leave it on there for a few weeks, is suprisingly hard to shift. I've never noticed any black smoke or puffs from my car either. Always used Tesco 99 and nothing else.

  • 7 months later...

Just did a search for 'Black Spots' and found this old thread - I've just noticed black spots on my car this morining, they're mostly on top of the rear bumper, along with some streaks on the boot. I've had the car for a week, having only done 250 and have still not pushed it too hard.

Are these the sort of marks that you're referring to?

P1060075.jpg

If so, I think it may have something to do with the rear wiper assembly directly above, rubber deposits maybe?

  • Author

Just did a search for 'Black Spots' and found this old thread - I've just noticed black spots on my car this morining, they're mostly on top of the rear bumper, along with some streaks on the boot. I've had the car for a week, having only done 250 and have still not pushed it too hard.

Are these the sort of marks that you're referring to?

P1060075.jpg

If so, I think it may have something to do with the rear wiper assembly directly above, rubber deposits maybe?

no thats not quite it (but similar) the marks I was refering to are uniform accross the back, definatley made and distributed from the exhaust by the air effect at the back of the car... this pattern (and the streaking, that wasn't on mine) does suggest dirty water, as you have already descibed..

I'd suggest thats dirty wiper fluid too :thumbup:

dont worry if you do get the sooty marks though, no big isue, most people have seent them ;)

Check inside the boot in case the wiper motor has melted the casing.

Check inside the boot in case the wiper motor has melted the casing.

Just checked - all OK there. Thanks for the heads up :thumbup:

Mines had that when I first had the TMC box fitted.

They come off easy though with the PW and a good foaming so its no bother.

I run on BP Ultimate (only high octane stuff we can get up here) and get the same thing. The smoke was partially bad the other day. I had been pottering around for a couple of days in traffic with the DSG in drive. No hard acceleration or high speeds for probably 50 or 70 miles. Then when I did put my foot down there was a bit of smoke out the back but after that it was fine no smoke. It seemed like the combination of the turbo kicking in, higher temperature and higher pressures and just blown out all the crap that had built up in the exhaust.

The end of the exhaust is always sooty as if it is running to rich. A guy I work gets the same sooty exhaust using Ultimate. The petrol is probably not as clean running as they claim.

  • Author

I run on BP Ultimate (only high octane stuff we can get up here) and get the same thing. The smoke was partially bad the other day. I had been pottering around for a couple of days in traffic with the DSG in drive. No hard acceleration or high speeds for probably 50 or 70 miles. Then when I did put my foot down there was a bit of smoke out the back but after that it was fine no smoke. It seemed like the combination of the turbo kicking in, higher temperature and higher pressures and just blown out all the crap that had built up in the exhaust.

The end of the exhaust is always sooty as if it is running to rich. A guy I work gets the same sooty exhaust using Ultimate. The petrol is probably not as clean running as they claim.

I think its just the car, they all do it... dont think its the fuel, in fact I'd be inclined to think it would be worse with 95 (less detergents ect)

this is a thread revival, (a year old?) my car was new to me when I started it (I now have 25,500 miles on!) after many meets and chatting to many owners, its all similar , its just "normal" I believe, cant remember the last shiny vRS exhaust I saw! lol...

  • 3 weeks later...

Just had the bike out for a run yesterday, first time this year and after a bit of enthusiastic riding in low gears. Nothing above 70 mph you understand, I had a look round the bike and noticed the ends of the exhaust had the same sooty specs on the exhaust. I never noticed this last year and was wondering if BP had changed the additive formula in the 97 ron petrol and that’s what’s causing the soot

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