mortymower

I bought an 87 951 and its done this since I bought it but I got a good deal on it so I figured it was okay. The car runs very strong with an autothority maf but it runs WAY to rich (I think) at idle when I go back there to the exhaust there is actually a cold black liquid coming out in a thin spray at all times. When you rev it black smoke comes out, not a ton but you definately notice it. This is fuel right????

Could this be the chips or the fuel switches on the DME flipped wrong, or the MAF? Dont have an AFR gauge so I dont know whats up

Should I be really concerned, when I drove it back I drove 650 miles and used less than 1/3 quart of oil. Im about to pull the engine but i want to make sure i know the cause so when i put it back its fixed

special tool

Little carbon, little condensation, maybe a little fuel until the o2 sensor heats up - its normal.

mortymower

no no, its a lot like if you hold your hand there its black in 5 sec. And it does it no matter how warm???

Geneqco

Don't know about the black liquid... but I had black soot coming out of mine (I guess if mixed with some water vapour, it could be like you describe) when one of my injectors was malfunctioning. It was leaking - not closing properly - hence the rich condition. It would leave black carbon deposits on the driveway if left idling. It might be an idea to have your injectors checked.

special tool

I'm not asking, I am telling you. Its normal.

billindenver

I agree with Mr. Spagetti O. Mine has done it for 10 years. I think it's worse with the cat gutted...but it is what it is.

Geneqco

Mine wasn't normal - I guess it depends on degree. If it turns your hand black in a few seconds, I'd be checking my injectors at least as a precaution.

ausgeflippt951

When cold, I know that if I rev mine a bit, it'll shoot some oil/carbon/condensation/whatever out and paint a light coat on the driveway. It stops doing it after the car's warm... I just assume the piston rings're a bit warn oot.

...so then Special Tool, does this mean that my car is wrong?! Given that mine doesn't paint my hand at all when warm? It is stock, mind.

billindenver

IMHO, my car doing so is a combination of chipping the car, running my ARC2 rich and running without a cat. If your leakdown is typical, I doubt your rings are causing anything. If you burn a lot of oil which would be obvious by the look of the exhaust....then perhaps rings.

George D

Do you have a cat? If not, you don't ever walk behind the car in the morning with dress pants unless they are BLACK.

You should be ok, but have the af ratios checked, and make sure that the car is tuned properly. Other than that, listen to Special Tool.

George

mortymower

haha, okay well no cat here but i think one of my injectors is messed up, I am going to replace anyway so...
Special tool, didnt mean to question your authority, just thought it was crazy cause my last didnt do it but my last one had a kitty on it so there you go.

Geneqco

FWIW I now have none of these symptoms others have described after replacing my injectors.

George D

Stock cats on a modified 951 after a year look like the old filters on a 747 that allowed smoking. They are just NASTY. Take them out and your tail will spit chewing tobacco on your pants. Trust me, I've ruined a few dress pants walking behind my catless modified 951 in the early AM.

If you look at the black circle on my garage door, you will realize why I open my door prior to starting my 951.

Some would call this Art, some would call it something else.

It's funny at how there is actually a large circle of 951 snot on one of my garage doors.

George

maximus951

Whatever happened to be behind the car when it was started; bins, boxes, tools, me or the lawnmower all received a healthy oval shaped spattering of black speckles... I used to hate it but now that the car is gone, it's kinda cool. I agree with ST.

Mighty Shilling

+1!!! learned the hard way...

it's normal. both my turbo and 924S do this.