pewter82

I searched for this topic and found little or nothing. My 91 GT has a black residue in the ends of the tailpipe and small splatters of black specks on the bumper above. Is this a too lean condition? I use premium fuel and I did not notice this two months ago when I purchased the car. Does this become a major problem or something to not worry about?

Jason

82S Pewter/Navy 57k
91 GT guards/tan 56k RMB

nicobel

run Forrest run!!!
(jusk kidding)

Old & New

I would guess that short trips may leave water pockets in the rear muffler, which occasionally get blasted out after becoming an acidic mixture of carbon, corrosion and combustion products. Just a guess. Some people have been known to drill a tiny hole in the muffler to alleviate this problem.

Jeff McVicar

It means its running a little rich........ if you are running premium you can try running the 87 cheapy grade. It is more volitile and if it doesnt create a valve ping (under acceleration) it may even give you more horsepower.....by running a little hotter and leaning it out a bit. It doesnt make sense when you dont know whats up but low octane is more flamable than high octane. High octane will make it run smoother but may rob horsepower if the compression isnt there to properly detonate it. Try the mid grade and even the low grade. It may give it a noticable kick

Jeff McVicar

That too hahahaha

Randy V

How's about using a title that is representative of the subject? Makes it much easier for future archive searches. Thanks.

pewter82

sorry Randy, I'm not trying to make the board more difficult.

Old & New

Perhaps thread titles can be edited...

Randy V

Sure they can - by clicking on the little paper/pencil icon at the bottom right of the post.

But only up to 3 days after the topic was started.

Brendan

I had a rich running condition with my 87S4. The final fix was replacing the two temp sensors on the front of the engine. I believe the drivers side sensor on top of the thermostat housing was the charm. It is certainly worth a look-see for sure. This was the cheapest-most satisfying fix I have made on my car. I also had a vacuum leak on the PS rear fuel distributor which will cause the same condition I believe.

MikeN

Totally normal IMO. My GT spits a few black dots on the ground after some startups. Just normal condensation inside the muffler mixing with normal residue of combustion. If you have thick black deposits inside the muffler then it might be a rich condition, but if the car seems to be running good and the plugs look good then I wouldn't worry about it.

PorKen

Randy said: "But only up to 3 days after the topic was started."

So that's why everyone else can edit their titles...

Is there a page with current bulletin board switches? IE. 15 minute post text/3 day title edit windows, etc.

Randy V

Maybe somwhere in here (website of the forum software developer):

http://www.vbulletin.com/