Black sludge in throttle body

[BullRider]

Just wondering if anyone can tell me what might be up.

I just took my '01 RT/10 apart to get some frame work done (certification for registration)and when I pulled my smooth tubes off, I noticed some black sludge around the lip of the air flap on the passenger side intake.

I cleaned out both intakes when I had the car apart a few months ago. I'd guess there is only about 100 miles on the car since then. The sludge is black and its thick and sticky. It has only collected just on the area, on the throttle body itself (not the flap) just within a quarter inch of the area where the flap is next to the body (how's that for a technical explanation.. ) It's also only on the bottom edge, not the top.

I'm worried that over time the sludge might close up my intake to the point where idle is affected. Where is that crap coming from and how do I stop it from collecting there?

 

[dave6666]

What is the condition of your intake tubes? If they are OEM, ie: elastomeric, and you used solvent on them that could be a problem. Even the silicone ones can be affected by aggressive chemicals. Same could go for the rubber around your air cleaners.

What does it smell like? Is it soluble in water? Gasoline?

PICS???

 

[BullRider]

Car is at the frame shop right now, so I can't take any photos. Not water soluble from what I can tell. Could be rubber around the air cleaners, I guess. They are brand new. Maybe they're bleeding muck. I haven't used any solvents or chemicals on anything up there except for carb cleaner on the actual throttle body. Hopefully the sludge stops coming out after some time. I'll keep checking every couple of weeks and see if it gets any worse.

Any other ideas from anyone?

 

[ViperTony]

Thought: check the vent line that runs from the valve covers to the air box. You may be getting blow-by its sent through the vent tube into your air box which makes its way back through the throttle bodies. You can see pics of the vent tube here: http://forums.viperclub.org/illustr...e-breather-system-puke-tank-photos-guide.html Disconnect the tube and stick your finger in there to check for oil or 'sludge'.

 

[puma]

i agree, must be oil vapor from the valve cover vent.

 

[Tom F&L GoR]

The oil/water vapor from the crankcase is warm and when it meets the incoming air, it condenses and falls. That may help explain the deposit pattern. Also, the air velocity where the flap (throttle plate) is near the wall (throttle body) is high, so droplets won't land there. All this shouldn't affect idle, since the air consumed at idle comes through the idle air control valve. What it may do is make the transition from idle to throttle on (driveaway) a little less smooth.

 

[dave6666]

Not to suggest bigger problems, but if you are getting such an amount of oil from the valve covers to create sludge in the TB's, that there is a blow-by or valve issue?

Or would driving the snot out of it more often clear the snot out of it?

 

[Tom F&L GoR]

First, may I suggest that all those folks that store their Viper, but feel the need to start 'er up for a few minutes every week, are adding exactly this kind of material to the inside of the engine. Yes, the oil sloshing around keeps the stuff from sticking but the additives in the oil are getting used up to satisfy the human need to hear the car run. When it just sits in the garage and idles, the oil will never warm up and boil off the water and fuel condensates, so the additives have to do the heavy lifting. It's actually a quick way to "use up" the oil.

Off the soap box now...

Some amount of this is normal. In fact, crankcase ventilation was the biggest air pollution creator by far, so the Positive Crankcase Ventilation (PCV) valve was the first emission control device. However, the baffles in the rocker cover should keep much of the oil in the crankcase so that what comes out the tube is mostly water vapor. Depending on your driving style, there may also be fuel in the oil that vaporizes and exits via the PCV tube. This unburnt and partially burnt fuel is much more likely to cause sticky deposits. Do you use a lot of (or did your recently add) an aftermarket fuel additive? What does the vapor smell like?

 

[triblk6spd]

Does the Viper have a standard issue PCV system like say the Vette or is it a modified version of one? I had the PCV system on my previous Vette completely removed and it was one of the best things I ever did to it. Like someone stated earlier I had to get the oil warmed up real good every time I drove it though.

 

[RAYSIR]

First, may I suggest that all those folks that store their Viper, but feel the need to start 'er up for a few minutes every week, are adding exactly this kind of material to the inside of the engine. Yes, the oil sloshing around keeps the stuff from sticking but the additives in the oil are getting used up to satisfy the human need to hear the car run. When it just sits in the garage and idles, the oil will never warm up and boil off the water and fuel condensates, so the additives have to do the heavy lifting. It's actually a quick way to "use up" the oil.

Exactly, Tom. I've been in the car storage business since '73 and the worst thing you can do is keep starting the engine and not getting the oil up to temp to vaporize all the fuel and contaminant you just put into it with a cold start. Guys just don't get it!! Leave it sit until you can drive it. Do a pre-oil by disconnecting the ignition, crank til oil pressure read then start it if it's been sitting a long time. The coking around the throttle plates is normal for FI with the PCV in the intake. Even see alot of condensation on the inside of Valve covers and on dipsticks when start and stop and oil doesn't get hot.

 

[Jack B]

Just wondering if anyone can tell me what might be up.

I just took my '01 RT/10 apart to get some frame work done (certification for registration)and when I pulled my smooth tubes off, I noticed some black sludge around the lip of the air flap on the passenger side intake.

I cleaned out both intakes when I had the car apart a few months ago. I'd guess there is only about 100 miles on the car since then. The sludge is black and its thick and sticky. It has only collected just on the area, on the throttle body itself (not the flap) just within a quarter inch of the area where the flap is next to the body (how's that for a technical explanation.. ) It's also only on the bottom edge, not the top.

I'm worried that over time the sludge might close up my intake to the point where idle is affected. Where is that crap coming from and how do I stop it from collecting there?

When you make a hard right corner at high rpm's the oil is pushed out of the left side valve cover and back into the intake thru the breather tube on the valve cover. On my car it was exacerbated by the T&D rockers. They flow more oil to the valve train. I had to put a puke can in to solve the problem.