White Smoke & Funky Smell

[LFD2037]

My rig smokes a bit @ start-up. It lightens up after running a bit and then stops smoking once I have driven a bit. It smells like fuel a bit to me. Adding oil yesterday to my motor I noticed the oil kind of smells like fuel as well. Any clues as to why:
white smoke that smells like fuel
oil that smells like fuel
do these 2 have a common problem

170K miles, no CEL, newish #1 O2 sensor, 11-11.5mpg (but I let it warm up every morning & mostly city driving).

***ETA***I'm losing zero coolant. Monitored it for 6 months & not a drop gone. The exhaust smoke/smell has been doing this since I bought it w/155K miles. Never smelled the oil before so IDK how long it's smelled like oil. If I run all highway I get 13.5mpg. Thanks.

***ETA***
I changed the OP to say that it does in fact stop smoking after it warms up and I drive it a bit.

 

[powermad]

You could have an injector stuck open and when the engine is shut off it leaks out into the crankcase.

 

[SmokingRocks]

Generally this is your guide to start diagnosing by the color of smoke:
WHITE = coolant
GRAY/BLUE = oil
BLACK = fuel

If you have other colors be afraid.

Does it smell sweet?

I would do a leak down test ASAP and limit your driving if this vehicle until you know what's happening.

This sounds like it's going to be head gasket related. A leak down test will help confirm.

 

[LFD2037]

Generally this is your guide to start diagnosing by the color of smoke:
WHITE = coolant
GRAY/BLUE = oil
BLACK = fuel

If you have other colors be afraid.

I would do a leak down test ASAP and limit your driving if this vehicle until you know what's happening.

I'm losing zero coolant. Monitored it for 6 months & not a drop gone. The exhaust smoke/smell has been doing this since I bought it w/155K miles. Never smelled the oil before so IDK how long it's smelled like oil. If I run all highway I get 13.5mpg. Thanks.

 

[LFD2037]

You could have an injector stuck open and when the engine is shut off it leaks out into the crankcase.

This was my guess. Easiest way to test them???

 

[Mr Cimarron]

I would get a Blackstone oil analysis done.

 

[BILT4ME]

Also for diagnosis:
Continuous blue smoke: Piston Rings
Blue smoke on start-up, then goes away: Valve Seals
Blue smoke on DECELERATION: Valve Seals
Blue smoke on ACCELERATION: Piston Rings
Black Smoke on ACCELERATION: Too much fuel
White smoke: Head gasket / coolant loss into the combustion chamber

I would recommend a Blackstone oil analysis. This can identify if you have excess gasoline getting into your oil and diluting it. This will also check for any coolant loss into the oil.

 

[SmokingRocks]

Oil analysis and a leak down test. That is where I and most mechanics would start.

 

[LFD2037]

Thanks. I'll start w/oil analysis & leak down. Is this a coolant system leak down or cylinder pressure leak down or ??? y'all are suggesting?

 

[scottryana]

Cylinder pressure. People think your rings are shot and letting gas past the rings and into the crank case.

 

[LFD2037]

That wouldn't explain the exhaust situation though, correct?

 

[scottryana]

Could be 2 things happening. Gas getting by your rings ending up in the crank case and oil getting by your rings ending up in the combustion chamber. Both are common with worn rings.

Pull the plugs and test the compression.

 

[SmokingRocks]

Cylinder leak down test is much more descriptive than a simple compression test.

With a LDT you can figure out where your seals are bad. Open up the oil filler cap and listen for leaking air sound, if there is then your piston rings are worn beyond spec. Put a rubber glover over the tail pipe, if it starts to inflate then your exhaust valves are leaking, do the same for the intake and it will show if your intake valves are leaking. Look for bubbles in your coolant reservoir that would show your HG being toast.

 

[LFD2037]

Thanks. I'll send off for OA next week. If it shows fuel in the oil then I'll do the leak down test (it sounds very time consuming so hopefully I won't need to do it!).

 

[powermad]

The leak down test that is being referred to is for the cylinders only.
To test the injectors you will have to remove them and send them out.

 

[SmokingRocks]

@LFD2037 The leak down test isn't that hard to preform. You can rent the tester from autozone, all you do is take the spark plugs out, hand crank the engine (wrench on the crankshaft nut) to get the cylinder that you're testing to top dead center (TDC) to make sure all the valves are closed. Then screw the adapter into the plug hole, apply pressurized air and check for leaks. Repeat for other 5 cylinders

There is a good youtube tutorial about it by Ericthecarguy I think

here:

 

[LS1FJ40]

I have the same symptoms (3FE not 1FZE). White smoke. Smells like fuel. ZERO coolant loss. Only I have really crappy gas mileage too. I suspect I have clogged cats, bad O2 sensors, and she's due for new plugs, wires and cap. And maybe injectors need cleaned/replaced. And...

 

[LFD2037]

I changed the OP to say that it does in fact stop smoking after it warms up and I drive it a bit.

 

[skhochay]

My rig smokes a bit @ start-up. It lightens up after running a bit and then stops smoking once I have driven a bit. It smells like fuel a bit to me. Adding oil yesterday to my motor I noticed the oil kind of smells like fuel as well. Any clues as to why:
white smoke that smells like fuel
oil that smells like fuel
do these 2 have a common problem

170K miles, no CEL, newish #1 O2 sensor, 11-11.5mpg (but I let it warm up every morning & mostly city driving).

***ETA***I'm losing zero coolant. Monitored it for 6 months & not a drop gone. The exhaust smoke/smell has been doing this since I bought it w/155K miles. Never smelled the oil before so IDK how long it's smelled like oil. If I run all highway I get 13.5mpg. Thanks.

***ETA***
I changed the OP to say that it does in fact stop smoking after it warms up and I drive it a bit.

what you are describing is a normal behavioral for this rigs. They do spit a bit of un-burdened fuel into exhaust system so when CAT converter is cold you will see this gray/blue smoke and smell of gasoline and burned oil when the CAT warms up smokes goes away but smell of gas or very nasty odor still present more noticeable during the colder weather, plus you have 170K so the rig naturally take a bit oil by design (manual page 201) with this millage tolerance are grated so it will burned that oil too. So as log you do not have smoke all the time and a lot of it, which is indication (see comments above). Coolant in the cylinder is a most common one because of the burned cylinder head gasket. But again we can't accurately diagnose based on few symptoms.

 

[LS1FJ40]

Would this smoke be more pronounced (heavier) if the CATs are clogged? I have original CATs on my 92 and I'm guessing they are clogged up. Going to deCAT this spring when it's warmer.