Black Oil/Dust on Back of Car

[4ord GT]

Have any of you noticed a black soot buildup on the back of the car. It is the same type of thing you would expect if you had an oil leak. I have gone over the car from top to bottom and see no fluid leaking anywhere. Has anyone else noticed this on their machine. Maybe it is normal due to the exhaust exit location? :ack

 

[FrankBarba]

This should be exhaust residue. Comes from the car running rich. We experience this on the vipers all the time with rear exit exhaust.

 

[Neilda]

I have an (old) Aston that's running rich at the moment and leave the same residue you've mentioned. So I think Frank is right.

Is this likely to be an issue with the cars electronics though? I had always thought that on new or modern cars that the fuel mixture (rich/lean) was adjusted electonically... so that if you put in 98 or 93 RON (for example) the car would adjust itself.

 

[c_steve]

I get this on the rear quarters of my SPF Cobra Holley carbed 500 HP no emissions engine that intentionally is tuned "a little rich" to preclude detonation if I get a bad load of gas but, I am suprised w/ an elex managed engine that there is any appreciable ammount of "unburnt hydrocarbons"emmitted.....wonder how the engines will stand up to an OB emmissions test when req'd.....Anyone passed a Calif emmissios yet??? Steve

 

[4ord GT]

Am I correct in saying that this is something that is only occurring on my GT?. I haven't heard anyone say that they have noticed it on their Car. Thanks for the Input.

 

[DLKGT]

Running Man - I also have the same oil/soot/black dust on the rear of my GT. Since I have a yellow car, the black "stuff" is very easy to see. Since the inside of my exhaust pipes are very black and sooty I figured that most of it must come from the exhaust.

However, the leading edge of the side scoops also get black and that could hardly be exhaust. The dirt on the scoops must be a combination of brake dust from the front wheels along with regular road dirt. Some of this must also get deposited on the rear of the car as well.

Also with regard to Calif. emmissions test - mine was purchased in CA so I did not have to go through the test, but several other CA GT owners I have met did purchase out of state and had to have them smog tested to register in CA. No one has indicated that the test was any problem.

 

[c_steve]

Low pressure area @ rear causes "whatever " to be deposited on rear ( any dampness in the air will accumulate and cause "whatever" to adhere???? Glad to hear that a # of cars brought into Ca did in fact undergo and pass Ca emissions... Steve

 

[Vic]

One of 19 in Germany has (or had) a problem with his transaxle breather vent, where it was releasing oil. The back of his car was also coated with soot and dust. He was in process of having it fixed, outcome unknown.

Don't know if this is related to your situation, but maybe its something to look into?

 

[4ord GT]

Thanks to all for the input.

 

[gtjoey]

Like yours mine too creates the same lets say soot/ residue,as you know we are both in the northeast, the weather has gone from 0 to 70 to 25 degrees over the last couple of weeks. The management program will adjust the timing, engine load and fuel during these changes when going from stone cold to full engine temp. TOTALLY NORMAL, we are not talking about blue run on vapor , like blow bye ,just the soot around the bumper ect. We sure get spoiled as we soon forget that when we owned 442s, gtos,dodge hemis ect, that you used to choke to death just idling the car. How a 100 year old design can burn so clean at 500 hp is unreal. We forgot that in those days you were also breathing tons and tons of lead too oofah!! p.s. a little wax on a pad will cut right through it , just wash first , no need for compound :thumbsup gtjoey 1314 with the cleanest pipes in town :biggrin