BrianB16A2

I was curious to find out what causes greyish maybe blackish

BrianB16A2

Smoke when I open vtec. When I open it u can see more of the smoke.

Lizardslap

possible needs a valve job from a cold start like first start of the morning if it smokes get out and look at the tail pipe then its the valves

a compression test / leak down test will give you an all the information you need

for a compression test if the compression rises sharply from a dry to a wet test its rings if not its the valves

but idk how your gonna test that in the winter unless you got a warm day

BrianB16A2

Thx bro and yea probably near impossible to tell in the winter hahaha. Just will have to wait till spring or summer.

EsotericImage

iTrader: (8)

most likely rich as its open loop at WOT.
then whatever carbon has built up might also be getting burned off

Fnix

iTrader: (1)

Is that also what causes a smell of fuel, oil when doing high revs?

EsotericImage

iTrader: (8)

shouldnt smell oil..

if you do, then you have either ring or valve issues

BrianB16A2

I don't smell anything when I open vtec just see lots of smoke nothing ridiculous tho. Anyone narrow it down precisely for me?

JoeBlue

Sure, do a compression test.

If the compression is fine it's your valve guides. There narrowed it down for you enough? If you are smelling fuel you have additional issues, you should back track your fuel lines for leaks first, and then test your fuel pressure. Maybe put some work into searching for the answers on the site, I know for a fact this has been asked before.

BrianB16A2

How can I do this test ? What all do I need

B serious

iTrader: (1)

To do a compression test, you need a compression tester.

Remove all the spark plugs. Screw the tester into one cylinder at a time. Pull the 15A PGM FI fuse. Crank the car with your foot all the way down on the gas pedal. I usually crank till the needle stops. Or use a standard amount of cranks for all cylinders.

B serious

iTrader: (1)

A little smoke is not abnormal during VTEC, high revs, or any time crank case pressure and engine load are high.

It's an over - rich condition, carbon is being burned out of the exhaust system, and it's normal to consume a small amount of oil.

BrianB16A2

So when I open vtec and white greyish smoke comes out it's normal?

B serious

iTrader: (1)

Depends on the amount of smoke. The car is running rich and the exhaust is at high velocity. So a little puff is pretty normal.

BrianB16A2

And if it's more than a little puff then it's a valve issue?

BrianB16A2

Or rings?

B serious

iTrader: (1)

No. If there's just a puff at hard acceleration, there's no real issue. It's a Honda. So check your oil often. Buying a new OEM Honda PCV valve helps also (if it hasn't been replaced already).

Do a compression test or leak down test. It will tell you how the cylinder is sealing. If the cylinder is sealing well and the car still burns oil, you can deduce that it's coming through valve seals.

The car is going to burn *some* oil between changes. It's not realistic for a 8200RPM motor with super short gearing that always lands you in high RPM territory to burn 0 oil.

95Sedan

my h22a smokes a bit under WOT, all of my cars have always smoked under WOT. as said above believe a little is normal.

BrianB16A2

Alright thx guys.

TomCat39

I'm not sure why a few different people said grey smoke is from running rich.

Pure white smoke (steam) - Water/Coolant burning
Bluish smoke - Oil Burning
Black smoke - Running Rich - unburnt fuel/carbon
GREY smoke - Running Lean - Too little fuel

Being it's winter it's probably instant condesation. Like our breaths in the winter air, when you hit VTEC it's pushing out a crap load of hot air.

Wait until summer, have a buddy follow you and give her a good rip. Then see if you have any smoke issues and what color. Also do the rip after the car is fully warm.

B serious

iTrader: (1)

Colors of smoke are difficult to determine.

Unless you're running a ridiculously rich AF ratio, the rich burning smoke will appear gray.

Oil smoke isn't like...bright blue as the internet would have you believe. It's barely off-white blueish.

All this is hard to distinguish looking thru the rear view mirror. If he's saying gray smoke and it smells like fuel....and he's flooring it, you can assume he's looking at diluted soot from running rich or burning a little oil.

But I will agree that since it's winter, there will be some condensation coming out of the exhaust....especially at WOT. I have been surprised many times by people being alarmed by this phenomenon that is clearly visible from other cars every single time they drive. It's strange.

But...anyone with a Honda (or any high RPM/high HP per liter motor) should expect atleast a small amount of oil consumption...and should check their oil often.

As far as smoke on WOT goes, any internal combustion engine will puff a little unburned fuel or soot of some sort out of the tail pipe when you floor it. It's normal.

TomCat39

Yeah, most definitely.

Partly why I suggested waiting till summer and have some one follow.

Everything is in shades... So the colors are tinting of the exhaust smoke. Bluish tint, oil.. Pure white, water, faded blackish looking, fuel, normal lighter grey not darkish grey, lean.



Really need someone behind you when you floor it to see what color it has to it. And you can't really judge during winter being it's puffing excessively from the cold naturally. So in summer if they have a hard time seeing it, then it's not usually enough smoke to be worried about.

Only time during winter I'd be worried is if it billowing smoke constantly, cold, hot, idle, half throttle, wide open throttle, then there might be something wrong.

JoeBlue

You can tell what it's burning by smell and taste if you stand behind it while it's running. If it were actually burning something because of a wear issue it would have a distinctive smell/taste. Oil burning is acrid and makes your eyes water up. Glycol (coolant) is even more of the same, but it has a sweetish smell to it. Excess fuel would just smell like it's running very rich. Piston rings smell like burning metal (if you have ever welded you would know what I mean by this)...




Either way if it's doing this during normal driving and noticeably more so during vtec change over then you should still do a compression check. Oreilly's had the kits for like $40 or so before the holidays. I bought an extra in case I need it myself and it's a good kit to have if you are doing your own work. It's always better to check it to make sure than to assume it's ok. Once you get an idea of what is ok from an engine you will be more capable of being able to tell when something is actually wrong without the tools around you or HT to hold your hand. Some skillsets and knowledge are always useful...

BrianB16A2

Thx everyone I really really appreciate all the feedback. This will def help come spring time. I'm sure it smokes a little when I drive normal. I can't see it they the rear view but when I crack vtec I see it clearly. It's like a greyish white. I now have an idea. Thx