I've noticed that after my truck idles for about 12 to 20 minutes(like when I go in the store and the wife stays in the truck) whenever I pull off and press the gas, I get heavy white smoke pouring from the exhaust and it only does it for a couple seconds. Then it's fine, never happens at Red lights and like I said it has to idle for a while. What could be causing this and how would I test to see if that would cause the problem? I thought head gasket but I don't notice any fluid disappearing and also no air bubbles coming out the radiator when the cap is off
Heavy white smoke after long idle
- Thread starter Robbiec16
- Start date
Mooseman
Moderator
djthumper
Administrator
Unusual problem. Most times when head gaskets fail, it happens pretty quickly. I'm wondering why the vehicle has to idle for a while before the smoke appears, and from what the OP writes, goes away after a minute while driving.
So to me, this is something (oil or coolant) leaking into the cylinders.
Valve guides/seals will do that. Head gasket will leak all the time because of radiator pressure forcing it into the cylinders.
Like Mooseman said, take a smell.
Good luck, keep us posted.
So to me, this is something (oil or coolant) leaking into the cylinders.
Valve guides/seals will do that. Head gasket will leak all the time because of radiator pressure forcing it into the cylinders.
Like Mooseman said, take a smell.
Good luck, keep us posted.
I'm on the same side with those pointing hard at the Head Gasket failure as the culprit. But the story of the "White Smoke" can get more complicated to repair and as such more expensive as time goes by. Symptomatically its a fairly easy thing to diagnose: Plumes of White Smoke intermittently appearing in the exhaust stream. However, two investigations should be made to nail down how much time you have before the engine declines and finally spins crankshaft bearings and seizes up, Here are the reasons why:
Symptom #1 PEG -Poly-Ethylene-Glycol in the Oil Stream:
Besides being a sweet tasting fluid that stray dogs find delicious enough to drink if they locate any pans of the stuff sitting around (It paralyzes and kills them afterwards)... PEG is EXTREMELY ACIDIC. If Anti--Freeze-Coolant is allowed to enter the main supply of oil... as it is pumped and circulated through the engine... it reacts with the Babbitt Coatings on the surfaces of the Crankshaft, Connecting Rods and Camshaft Bearings...and dissolves those surfaces by chemical corrosion. The rotating assembly will eventually over-heat from friction and seize up and snag on the bearings, causing them to spin in place in the block, effectively lunching the motor. This condition of AF-OIL can be determined by examining your Engine Oil for what looks like Chocolate Milk instead of the expected amber green, healthy Motor Oil.
If you can see the Brown Mung on your dipstick...catastrophic engine failure is coming. The engine can be salvaged by a re-build involving flushing out all that crap and essentially install new bearings everywhere inside the engine. If you continue to drive with the Chocolate Milk in the Oil Pan, since the gooey liquid has no lubricating properties... therefore, the interior engine components have no protective thin film of oil separating stationary metal areas from metal rotating in the moving parts under normal Oil Pressure. The other bad feature of this Chocolate Milk Mung ...is that it is of a consistency that is much like pudding and as such, It makes it impossible for the Oil Pump Pick-Up Tube to suck in anything and after the pump cavitates... The entire engine is without any oil lubrication. The Metal to Metal contact in any circumstance can cause 50,000 miles of engine wear in a matter of days.
https://s-media-cache-ak0.pinimg.com/originals/6f/c4/c8/6fc4c8dce904972e47c5bd696c945307.jpg
Symptom #2: Oil Droplets floating in the Radiator just under the cap...
The presence of Engine Oil in the Anti-Freeze is an indication in the best conditions as a Blown Head Gasket adjacent proximal Oil and Water Passages shared between the Engine Block and the Heads (probably not the case in your motor), The worst case scenario is that for one reason or another, there is a crack in one or more cylinders in the engine block allowing oil to push through and enter the coolant passages. If the engine is to be saved, the motor needs dis-assembly and new bearings throughout before it is damaged beyond any hope of repair from continued use.
http://www.team-bhp.com/forum/technical-stuff/134621-do-i-need-change-head-gasket-3.html
Symptom #1 PEG -Poly-Ethylene-Glycol in the Oil Stream:
Besides being a sweet tasting fluid that stray dogs find delicious enough to drink if they locate any pans of the stuff sitting around (It paralyzes and kills them afterwards)... PEG is EXTREMELY ACIDIC. If Anti--Freeze-Coolant is allowed to enter the main supply of oil... as it is pumped and circulated through the engine... it reacts with the Babbitt Coatings on the surfaces of the Crankshaft, Connecting Rods and Camshaft Bearings...and dissolves those surfaces by chemical corrosion. The rotating assembly will eventually over-heat from friction and seize up and snag on the bearings, causing them to spin in place in the block, effectively lunching the motor. This condition of AF-OIL can be determined by examining your Engine Oil for what looks like Chocolate Milk instead of the expected amber green, healthy Motor Oil.
If you can see the Brown Mung on your dipstick...catastrophic engine failure is coming. The engine can be salvaged by a re-build involving flushing out all that crap and essentially install new bearings everywhere inside the engine. If you continue to drive with the Chocolate Milk in the Oil Pan, since the gooey liquid has no lubricating properties... therefore, the interior engine components have no protective thin film of oil separating stationary metal areas from metal rotating in the moving parts under normal Oil Pressure. The other bad feature of this Chocolate Milk Mung ...is that it is of a consistency that is much like pudding and as such, It makes it impossible for the Oil Pump Pick-Up Tube to suck in anything and after the pump cavitates... The entire engine is without any oil lubrication. The Metal to Metal contact in any circumstance can cause 50,000 miles of engine wear in a matter of days.
https://s-media-cache-ak0.pinimg.com/originals/6f/c4/c8/6fc4c8dce904972e47c5bd696c945307.jpg
Symptom #2: Oil Droplets floating in the Radiator just under the cap...
The presence of Engine Oil in the Anti-Freeze is an indication in the best conditions as a Blown Head Gasket adjacent proximal Oil and Water Passages shared between the Engine Block and the Heads (probably not the case in your motor), The worst case scenario is that for one reason or another, there is a crack in one or more cylinders in the engine block allowing oil to push through and enter the coolant passages. If the engine is to be saved, the motor needs dis-assembly and new bearings throughout before it is damaged beyond any hope of repair from continued use.
http://www.team-bhp.com/forum/technical-stuff/134621-do-i-need-change-head-gasket-3.html
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smt 59
Member
Yes... As long as BOTH conditions of Chocolate Oil and Oil Droplets Floating on the top of the Coolant inside the Filler Neck of the Radiator are NOT present. But you will have to grit your teeth because on a "Scale of Repair Difficulty" of 1-10... THIS one is indeed a 10....and a 12.5 on the "Mechanical PITA Richter Scale" as well. I am in the middle of this nightmare right now and even when possessed of solid "Mr. I-Can-Fix-ANYTHING" Chops... it is a Bear because of the need to buy and use Specialty Tools and doing things that require a high degree of mechanical precision. Even though my situation involves the need to perform Replacement of the Head... All of the steps to the R&R are identical to merely doing an R&R of the Head Gasket. Please have a look at this GMT Nation Post Nightmare-in-Progress and you will understand:
http://gmtnation.com/forums/threads/the-85-000-00-gm-4-2l-engine-repair.14423/
http://gmtnation.com/forums/threads/the-85-000-00-gm-4-2l-engine-repair.14423/
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There are no oil droplets in the coolant. I bought this truck 2 months ago and the first thing I did was change the oil. It was a few quarts low, they claimed they changed it every 5k. Any ways the oil was super dark, and nowhere near chocolate milky. I put synthetic in it. So I have been puzzled with the color lately trying to figure out if it's contaminated or not. It does have a slight color variation but nothing like what I've seen online for coolant and oil mixed. But I still had the old jug that I took out of it so yesterday I did the sizzle test and it sizzles. It also sizzles when I take the dipstick out and use that oil. So I'm guessing there is coolant in the oil. The trucks runs great, doesn't overheat and doesn't smoke constantly like a usual head gasket leak. Like I also said before, no bubbles coming from the radiator.
Please also review the Signature Article on this job that prompted my attempt well documented by @Mooseman and consulting him directly is a wise thing to consider, If you are going to go to this much difficulty, having the head looked over by a Machine Shop for any possible problems before re-installing it is also wise:
http://gmtnation.com/forums/threads/how-to-remove-i6-oil-pan-in-vehicle.12230/#post-470387
http://gmtnation.com/forums/threads/how-to-remove-i6-oil-pan-in-vehicle.12230/#post-470387
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Mooseman
Moderator
I once had a cracked head in my old Jimmy that had a misfire on the affected cylinder and the oil was contaminated with coolant. The coolant would migrate past the piston rings and into the oil. If your oil is milky/chocolaty, no need to have it analyzed. It's coolant. Check your spark plugs and if one is really clean, that's where it's getting into the engine. If you have a borescope, checking each one will confirm this with a really clean piston.
While searching for the "sizzle test" (I just learned something today!), I found this video on block testing to test for exhaust gases in the cooling system. I think this would be worthwhile for you to do this test.
While searching for the "sizzle test" (I just learned something today!), I found this video on block testing to test for exhaust gases in the cooling system. I think this would be worthwhile for you to do this test.
Head Gasket-Coolant Leak = White Smoke
Bad Valve Guides & Seals = Light Blue Smoke
BlazingTrails
Member
- Apr 27, 2014
- 19,409
I have never heard of this method of testing for head gasket leaks. The method I have always preferred to use was a radiator pressure test. But there are MANY signs to look for with a blown head gasket so it is usually pretty easy to diagnose, but def not always! I recall a couple of scenarios where I would have loved to have this test kit. Good info for sure.
Mooseman
Moderator
Isn't it possible that it could be the intake manifold gasket?
They give off the same symptoms am i correct?
I have now seen coolant loss, and slight oil contamination.
Still no overheating, and no bubbling in the radiator.
The smell that comes from the exhaust isnt sweet smelling, when you guys refer to a sweet smell im thinking the smell of syrup. Smells regular
Im trying to find a way to avoid tearing the engine down to see which one it is. There has to be a sure fire test out there for this.
And how hard is it to remove the intake manifold on these engines
Only codes that have been thrown are
P0420 Catalyst System Efficiency Below Threshold (Bank 1)
This was when i first got the truck in October and i cleared it,it never returned
A constant code i do receive after being cleared is P0440. I changed the gas cap and observed no leaks from the neck, so i assume there is a leak with that elsewhere
I cleaned the throttle body after replacing the actuator for the AC. At start up, the engine will idle over 1200 for about 30 to 40 seconds before lower down to about 700 and will stay there. It will dip though to below 500 then recover multiple times off and on while idling.
I'm just trying to give more symptoms that i have been experiencing. The truck gets drove 10 miles a day and i havent had the money to take to the shop and i definitely dont have the money for an engine swap or rebuild right now.
I also dont have the equipment or knowledge of how to do a leak down test.
They give off the same symptoms am i correct?
I have now seen coolant loss, and slight oil contamination.
Still no overheating, and no bubbling in the radiator.
The smell that comes from the exhaust isnt sweet smelling, when you guys refer to a sweet smell im thinking the smell of syrup. Smells regular
Im trying to find a way to avoid tearing the engine down to see which one it is. There has to be a sure fire test out there for this.
And how hard is it to remove the intake manifold on these engines
Only codes that have been thrown are
P0420 Catalyst System Efficiency Below Threshold (Bank 1)
This was when i first got the truck in October and i cleared it,it never returned
A constant code i do receive after being cleared is P0440. I changed the gas cap and observed no leaks from the neck, so i assume there is a leak with that elsewhere
I cleaned the throttle body after replacing the actuator for the AC. At start up, the engine will idle over 1200 for about 30 to 40 seconds before lower down to about 700 and will stay there. It will dip though to below 500 then recover multiple times off and on while idling.
I'm just trying to give more symptoms that i have been experiencing. The truck gets drove 10 miles a day and i havent had the money to take to the shop and i definitely dont have the money for an engine swap or rebuild right now.
I also dont have the equipment or knowledge of how to do a leak down test.
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Robbie... Forget about removing the Intake Manifold... THERE IS NO COOLANT GOING THROUGH THE INTAKE MANIFOLD... By my reckoning...using your "Only 10 Miles a Day" vs the last time you posted here on your progress... you have driven at LEAST 360 Miles with a Blown Head Gasket remaining consistently as your most likely problem. The P0420 DTC is not only a strong earmark that you have a compromised Head Gasket... but your problems are beginning to compound expense-wise because the Leaking Head Gasket has now allowed the chemical contamination of your Catalytic Converter with Anti-Freeze-Coolant.... The Probable cause of the P0420 DTC.
http://www.aa1car.com/library/p0420_dtc.htm
The cascade that will follow soon will be this: You will attempt a 10 Mile per Day Foray.... and as you are driving along... the Engine Bearings will seize and begin spinning with the journals on the crankshaft and start making a horrendous noise as the Waste Foam Cast Aluminum Block is destroyed as the rotating parts and pieces struggle to continue under the influence of your foot on the gas pedal... and if it happens at low speed .... the engine will lock up and that will be that. If it happens at highway speed... same story... but the occurrence will be much more dramatic. The Engine RPM dropping precipitously low is fair indication that the parts are beginning to adhere to one another (bearings to journals-bearings to camshaft-bearings to connecting rods) and you need to change your Oil and Oil Filter.... right away.
Robbie... You are running out of time and options... but don't despair just yet:
At this point you have nothing to lose by considering doing what Scotty Kilmer recommends in these two videos with a liquid product he has used on many occasions to deal with Head Gasket Leaks... WITHOUT TEARING DOWN THE ENGINE. The stuff is called STEEL SEAL and I have NO PERSONAL EXPERIENCE TO VERIFY THAT IT WORKS.
caveat emptor (ĕmpˈtôrˌ)
We want you to succeed, Robbie... But in the absence of doing either an R&R of the Engine Head Gasket for around $2,500-$3,000 OR picking up a decent USED 4.2L Engine anywhere from $850-$1,500 ... you will have to make the decision to try STEEL SEAL on your own.
https://duckduckgo.com/?q=youtube+scotty+kilmer+head+gasket&t=ffhp&ia=videos&iai=3suQy44G_B0
https://duckduckgo.com/?q=youtube+scotty+kilmer+head+gasket&t=ffhp&ia=videos&iai=f6YF-3zMBqY
http://www.aa1car.com/library/p0420_dtc.htm
The cascade that will follow soon will be this: You will attempt a 10 Mile per Day Foray.... and as you are driving along... the Engine Bearings will seize and begin spinning with the journals on the crankshaft and start making a horrendous noise as the Waste Foam Cast Aluminum Block is destroyed as the rotating parts and pieces struggle to continue under the influence of your foot on the gas pedal... and if it happens at low speed .... the engine will lock up and that will be that. If it happens at highway speed... same story... but the occurrence will be much more dramatic. The Engine RPM dropping precipitously low is fair indication that the parts are beginning to adhere to one another (bearings to journals-bearings to camshaft-bearings to connecting rods) and you need to change your Oil and Oil Filter.... right away.
Robbie... You are running out of time and options... but don't despair just yet:
At this point you have nothing to lose by considering doing what Scotty Kilmer recommends in these two videos with a liquid product he has used on many occasions to deal with Head Gasket Leaks... WITHOUT TEARING DOWN THE ENGINE. The stuff is called STEEL SEAL and I have NO PERSONAL EXPERIENCE TO VERIFY THAT IT WORKS.
caveat emptor (ĕmpˈtôrˌ)
- n.
The axiom or principle in commerce that the buyer alone is responsible for assessing the quality of a purchase before buying.
We want you to succeed, Robbie... But in the absence of doing either an R&R of the Engine Head Gasket for around $2,500-$3,000 OR picking up a decent USED 4.2L Engine anywhere from $850-$1,500 ... you will have to make the decision to try STEEL SEAL on your own.
https://duckduckgo.com/?q=youtube+scotty+kilmer+head+gasket&t=ffhp&ia=videos&iai=3suQy44G_B0
https://duckduckgo.com/?q=youtube+scotty+kilmer+head+gasket&t=ffhp&ia=videos&iai=f6YF-3zMBqY
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Mooseman
Moderator
I HATE band aid solutions, which usually don't fix anything and usually cause more problems. I also can't stand Kilmer. Apart from being uber annoying, did you see his video on doing an oil change under a car with a jack?!?
Ericthecarguy has this video against such sealers.
My own experience with them, my BIL used it and it didn't seal the head gasket but did plug up the heater core.
If this type of work is beyond your equipment or capabilities, I would suggest you either find a friend that does or abandon the truck because it will be prohibitively expensive. Given the age of your truck, it may not be worth it. Sorry to be so harsh but a head R&R is way beyond the home oil change crowd. Even professionals have trouble with this engine, especially with broken head bolts and the timing chain. Definitely not for the faint of heart. But you FIRST need to confirm that it is definitely your head gasket. You asked for a sure fire way to test, one was given above along with other telltale signs.
BTW, please do not multi-post. If you need to add more info, use the edit button.
Ericthecarguy has this video against such sealers.
My own experience with them, my BIL used it and it didn't seal the head gasket but did plug up the heater core.
If this type of work is beyond your equipment or capabilities, I would suggest you either find a friend that does or abandon the truck because it will be prohibitively expensive. Given the age of your truck, it may not be worth it. Sorry to be so harsh but a head R&R is way beyond the home oil change crowd. Even professionals have trouble with this engine, especially with broken head bolts and the timing chain. Definitely not for the faint of heart. But you FIRST need to confirm that it is definitely your head gasket. You asked for a sure fire way to test, one was given above along with other telltale signs.
BTW, please do not multi-post. If you need to add more info, use the edit button.