Black soot from tailpipe

LM7Yukon · November 21, 2005

I'm noticing a thick black soot in my tailpipe. Has this anything to do with my ping at 2000 rpm and higher 60mph plus?

TonyMazz · November 22, 2005

I'm noticing a thick black soot in my tailpipe. Has this anything to do with my ping at 2000 rpm and higher 60mph plus?

<{POST_SNAPBACK}>

1. Since this is a new truck, I would take it back to the dealer and take them for a ride at 60 mph to show them.

2. The probable cause for this could be a connector that opens when the motor gets hot or a host of other things. Since a condition of this sort could be anything from mechanical i.e. valve guides allowing oil in the combustion chamber hence carbon or sparkknock, to timing issues, to sensor issues.

Simple answer is to bring it back, let the techs put a tech-2 scanner on it and read the truck dynamically to see what's going on.

There is no reason you should need to deal with this, as that's what a warranty is for...

Don't hesitate and ruin a good motor....take it back, take it back, take that thing right outta here....

lrymal · November 22, 2005

I'm noticing a thick black soot in my tailpipe. Has this anything to do with my ping at 2000 rpm and higher 60mph plus?

<{POST_SNAPBACK}>

You say "THICK". A thin layer of black is normal. By "THIN", I mean you rub your finger on it, it comes off on your finger and you can almost see the exhaust pipe metal where your finger rubbed.

You shouldn't be getting any ping at all any RPM, assuming your gasoline is at least 87 octane. Minor pinging is typically normal, but it shouldn't be chronic.

Finally, this is a dealer warranty issue, if your soot is THICK, and if the pinging is loud. If your dealer is like mine who gives you the run-around, ask for a similar truck to compare against. I'm assuming that the comparing truck would be like mine, QUIET with THIN finger soot. Tell them you want your truck to be exactly like that. You have rights and if they don't address your concerns, then start asking if your truck is a lemon, ask them what constitutes a lemon, ask them how often they get lemon. Push the word, LEMON on them even in casual conversaton. Do this with your sales guy, go to the public relations guy and do it, and to the GMAC financer if you used GMAC.

The fact that you show even a small degree of literacy regarding ''lemon'' tends to make a dealer a bit nervous, mainly because it demonstrates just HOW serious and concerned you are with a chronic problem.

TonyMazz · November 22, 2005

I'd check the gas you are using too....87 octane ...don't go for the cheapest as you started another post on gasoline, use the top-tier gasolines..not the cheap s**t.

Also look around under the hood for loose connectors, as your knock sensor may be intermittent and yet not throwing a code.

But a tech-2 scanner can capture the necessary details to see exactly what's happening on your ECU during the ping moments....again under warranty !!!!

lrymal · November 22, 2005

I'd check the gas you are using too....87 octane ...don't go for the cheapest as you started another post on gasoline, use the top-tier gasolines..not the cheap s**t.

<{POST_SNAPBACK}>

Good point:

Why Top Tier?

http://www.toptiergas.com/why.html

The intention of the TOP TIER Detergent Gasoline standards is to create a winning situation for gasoline retailers, auto manufacturers and drivers. Currently, many gasoline retailers provide fuels with lower-quality additive packages that can build up deposits on fuel injectors and on intake valves. Others can build up deposits in combustion chambers and may lead to intake valve sticking. These lower levels of additives can have negative impacts on engine performance and vehicle responsiveness.

TOP TIER Detergent Gasoline Retailers

http://www.toptiergas.com/retailers.htmlQuikTrip

Chevron

Conoco

Phillips

76

Shell

Entec Stations

MFA Oil Company

Kwik Trip/Kwik Star

The Somerset Refinery, Inc.

Chevron-Canada (B.C. only)

LM7Yukon · November 22, 2005

I'd check the gas you are using too....87 octane ...don't go for the cheapest as you started another post on gasoline, use the top-tier gasolines..not the cheap s**t.

<{POST_SNAPBACK}>

Good point:

Why Top Tier?

http://www.toptiergas.com/why.html

The intention of the TOP TIER Detergent Gasoline standards is to create a winning situation for gasoline retailers, auto manufacturers and drivers. Currently, many gasoline retailers provide fuels with lower-quality additive packages that can build up deposits on fuel injectors and on intake valves. Others can build up deposits in combustion chambers and may lead to intake valve sticking. These lower levels of additives can have negative impacts on engine performance and vehicle responsiveness.

<{POST_SNAPBACK}>

I agree, but top tier fuel is not prevelant in the north east. Only shell is avail, with few stations here in this part of the country.

TonyMazz · November 22, 2005

So rather than dink around with guessing..why don't you tell us all what you did with your truck...have you taken it back to the dealer ? What did they say ? What have you done to your truck, tune up, changes, modifications...etc....?

Are you taking it back to the dealer ?

LM7Yukon · November 23, 2005

So rather than dink around with guessing..why don't you tell us all what you did with your truck...have you taken it back to the dealer ? What did they say ? What have you done to your truck, tune up, changes, modifications...etc....?

Are you taking it back to the dealer ?

<{POST_SNAPBACK}>

went to 3 different dealers, they were stunned. Their scan tool shows no errors, yet they agree something is wrong. It only has 5500 miles in 6 weeks.

TonyMazz · November 23, 2005

So rather than dink around with guessing..why don't you tell us all what you did with your truck...have you taken it back to the dealer ? What did they say ? What have you done to your truck, tune up, changes, modifications...etc....?

Are you taking it back to the dealer ?

<{POST_SNAPBACK}>

went to 3 different dealers, they were stunned. Their scan tool shows no errors, yet they agree something is wrong. It only has 5500 miles in 6 weeks.

<{POST_SNAPBACK}>

OK.....take it back to the service department where you bought it.....

Arm yourself with facts, i.e. gas mileage records, where you buy your gas....

Tell the service manager you want to take a tech armed with a tech-2 with you and take him on the freeway....run 60 mph and let them listen, apply the tech-2 and do a freeze frame when it pings.

there may be no codes set, but there may be something wrong.

But just saying "look at my tail pipe it's black" will get you where you are today.

If that gets you no where ....go back to your sales person....request help...

If that gets you no where .....move up to the sales manager....if that gets you no where go to the dealer general manager.....if that gets you no where then go to the regional manager...get the picture ?

LM7Yukon · November 23, 2005

So rather than dink around with guessing..why don't you tell us all what you did with your truck...have you taken it back to the dealer ? What did they say ? What have you done to your truck, tune up, changes, modifications...etc....?

Are you taking it back to the dealer ?

<{POST_SNAPBACK}>

went to 3 different dealers, they were stunned. Their scan tool shows no errors, yet they agree something is wrong. It only has 5500 miles in 6 weeks.

<{POST_SNAPBACK}>

OK.....take it back to the service department where you bought it.....

Arm yourself with facts, i.e. gas mileage records, where you buy your gas....

Tell the service manager you want to take a tech armed with a tech-2 with you and take him on the freeway....run 60 mph and let them listen, apply the tech-2 and do a freeze frame when it pings.

there may be no codes set, but there may be something wrong.

But just saying "look at my tail pipe it's black" will get you where you are today.

If that gets you no where ....go back to your sales person....request help...

If that gets you no where .....move up to the sales manager....if that gets you no where go to the dealer general manager.....if that gets you no where then go to the regional manager...get the picture ?

<{POST_SNAPBACK}>

Got the regional manager involved. There scheduling the region engineer to test it. They think it may be an emisions issue with Calif requirements, and no top tier fuel avail in PA which falls under Federal regulations.