Soot on rear, above exhaust

Tw,

I have a white tacoma with the V6, 6spd manual. It is a 2011 with ~25,000 miles. I run moble 1 syn and change it every 3,500-4,000. i have changed the air filter at 10,000 and 20,000. does any one else have soot above the exhaust? i also live at 2,800 FT elv. and run 87 with the 10% ethonal. What do you guys think? i am blown away. do thease truck just run rich?

 

Yes, they run rich from the factory, particularly under open loop acceleration.

I personally shy away from ethanol, actually I've always run ethanol free premium fuel, and I have plenty of soot. Nature of the beast with these trucks.

 

well, looks like intake, and exhaust are coming soon, and the plug in device that plugs into the MAF from URD

 

Bust out the credit card! Lucky you!

I don't run a MAF calibrator myself, but you've done your research: that's about the only way to address the issue under hard acceleration. Just be sure to purchase your upgrades first, and get them to tune the calibrator to your individual setup/upgrades.

 

yup, I have enough points to get it all for FREE on my 2 credit cards! been saving for 6 years!

 

Just lop it off and dump it right over the axle. Problem solved!

 

I would, but i also want to solve the issue of unburned fuel. could cause O2 sensors to faul up quicker and suck, carbon build up on valves.. i could go on.

 

Before anything I'd get a Scangauge or Ultragauge so you can monitor your lambda values and timing. It could be a matter of sucky fuel (i.e. severely pulled timing could cause unburned fuel too). Have you tried higher octane, maybe 89 or 91?

If you were running rich the lambda values would be consistently less than 1. As far as timing, my 2.7L (2TR) cruises at ~25-30° BTDC, with dips into the teens on acceleration.

 

You cannot avoid a small amount of soot coming from the exhaust. If it is excessive enough to cause black smoke, THEN you may have an issue, but you can look at EVERY car and truck and if you run your finger across the inside edges of the exhaust pipe, you will find soot. Can't do anything about it. Soot is not unburned fuel. Soot is a RESULT of burned fuel when you are looking at exhaust output.

 

mine is visable on the rear panel, right behind the tire.

 

Not a matter of safe side or not safe side. federal law mandates that they run it as close to 14.7:1, so you cant play with it. Soot is going to happen on EVERY CAR on the road. The soot showing up on your fender has to do with several factors from where the pipe actually exits the vehicle to how fast you are driving. How about some pics? I would suggest maybe a small pipe end like a custom extension that adds 3 or 4 inches to the pipe length.