What causes visible smoke and how do I fix it.
Model year of your Acura?
Total odometer mileage?
Date and odometer mileage of last major service?
Typical mileage and time interval between oil changes?
What color is the smoke?
Under what conditions does it happen?
How many miles are on the car and how has it been maintained?
What year is it?
Are there any operating problems?
White smoke is generally water vaporā¦coolant from a breech somewhere or steam from a cold engine. In rare cases it can be tranny fluidā¦but Iāll wait for your detailed responses before going there.
Black smoke is generally carbonā¦from too rich a mix or poor combustion.
Blue/gray smoke is generally oil. On acceleration itāll generally be ring problems, on morning startup and/or under deceleration it could be valve stem seals.
Tell me more.
Blue smoke is from oil burning, usually from worn rings.
The remedy to cure the visual smoke test is to run a very rich mixture of thick oil, like 80 or 90 weight gear oil, or motor honey. My tailpipe smoked badly due to worn rings but passed emissions. 8 of 8 mechanics I spoke with wanted me to replace the engine. When I drained the oil and put in 5 bottles of STP oil treatment, the smoke was GONE. It passed all the smog tests. I went back and showed this to 3 of the 8 mechanics. They already knew it would work but were too corrupt to tell me. They really wanted me to buy a new motor (crooks). Perhaps fewer bottles of STP could have been mixed with some regular oil, but I used pure STP to be sure. Regular STP oil treatment in the blue bottle is thicker than STP in the red bottle for 4 cylinder engines.
Synthetic oil is supposed to be smokeless but is too thin and slippery to cushion the rings so it still smoked. Heavy gummy oil will seal worn rings and pass visual smoke tests.
Another tip. Retarding the ignition timing will reduce emissions and help it pass. Minus three degrees TDC with the computer wire disconnected is still within specs. A timing light can be purchased at Harbor Freight for $12. Some distributor caps require a special tool to loosen the bolt to adjust the timing. The tool is about $8 at most any auto parts store.
Vacuum leaks will make the car idle fast.
Premium gas is better to run during the test.
The motor should be warmed up well first before the test.
If you read the fine print on G2P - Guaranteed to Pass fuel additive youāll see that youāll never ever be able to collect on their double your money back guarantee when your car fails. Donāt buy it.
The emissions test has two categories: hydro carbons, and oxides. EGR hardware is related to the oxides test. Spark plugs, wires, ignition timing, etc., are related to the hydro carbons.
Mechanics often want to replace the O2 sensor without a valid reason. Watch out.
It took me only a few minute to replace mine but āthe bookā authorizes mechanics to charge 0.9 hours at the shop rate. Ouch.
Some smog stations that offer internet coupons are known to sabotage your vehicle by pulling off a vacuum hose then failing it for being ātamperedā with. There is no way in a million years that a vacuum hose will just fall off by itself because the vacuum sucks it on there. The coupon savings that brought you there is offset by the additional retest fee. Itās a scam. The guy at Saticoy/Winnetka pulled this dirty trick on me. I know this for sure because checked everything right before I took it to him. That hose was indeed on there when I took it to him, for sure.
After making timing adjustments or replacing various sensors It is a good idea to reset the cars computer by disconnecting the battery for a minute. This causes the computer to recalibrate itself the next tim the engine is started.
When the vehicle is cold, reach under it with a HAMMER and bang on the CATALYTIC CONVERTER, careful not to dent it, but hard enough to knock the carbon buildup off the platinum catalyst plates inside. Then start the car and rev on the gas to blow the carbon out. Repeat steps a few times and that will drastically improve your emissions test.
Never take a car that needs a little work to a mechanic who needs a little work. 
wise_consumers advice can be disregarded completelyā¦
Bob C, we need more information to answer your question. Year, make, model, mileage would be a good startā¦
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I second Caddyman.
Did your car fail the emissions test because of visible smoke, or did it fail a specific CO, HC, NOx, or CO2 test? Depending on what test procedures your area uses, visible smoke may or may not be related to failing an emissions test.
BTW wise_consumer,thanks for the chuckle.
If Wise Consumer is so wise, does he really think that the OP is still waiting for a response, two years after posting his question? Especially in a case where the OP was asked for additional information and then failed to ever provide that information, reviving a two year old thread does not make a whole lot of sense.
And, as Caddyman implied, the advice given by Wise Consumer about 80-90 weight oil and the use of STP is best ignored if someone wants to keep his engine running for the long term.
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Hi everyone, kind of had the same issue as the first post. I purchased a used 2012 mini S Cooper countryman last week and went for my emission test in New Jersey today. It failed because of visible smoke. It was the first time I saw visible smoke since buying it (Smoke was grey/white). There was a huge line at the inspection place and my car idled for about an hour there before I passed the test. No engine lights or anything in the car, and the smoke stopped after I drove a couple miles out and away from the place. I am going to go to a mechanic to have it checked but if you have any recommendations or anything, let me know!
Well, which is it?
First you state āfailed because of visible smokeā
Then you state āmy car idled for about an hour there before I passed the testā
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Same as above, pass or no pass??
I am assuming the smoke was seen coming out of the tail pipe and not from a wheel area or from under the hood correct??
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If we assume that āpassed the testā means you went through the test station, then you might try driving the Mini for at least a half hour before getting it tested again. Maryland suggests driving on the highway for a half hour on the way to the test station to give you the best chance of passing the test. Idling for an hour doesnāt count towards the drive time. If the NJ test is like ours, you will just get the ODB2 codes read after the smoke check. No smoke and no stored codes would mean you pass her, and maybe in NJ.
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Iām not making any suggestions until my very simple question has been answered
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Sorry for the confusion, I failed the test. I meant āpassedā for going through the center to get the car tested. On my vehicule inspection report it says I passed at everything, but the āvisible smokeā.
Smoke was indeed coming out of the tail pipe.
The car idled during an hour where I probably did less than a mile until I could enter the center and do the testing, so I agree conditions were definitely not the best.
I am bringing the car to a certified mechanic, so he checks if the smoke can come from something major and needs repair + will do the inspection too.
Is it the good way to proceed?
Did you buy your car from a dealership, or from a private party?
I ask because of the following:
- NJ law requires used car dealers to warrant that vehicles pass inspection. If a car fails, the dealer must pay for repairs or repurchase it.
If you bought it from a dealer, did you sign a waiver?
- The Waiver: Dealers may have you sign a waiver, separating it in the contract, which waives your right to have the vehicle pass inspection.
If you bought it from a private party, then you are on the hook for the repairs that are necessary in order to pass the emissions tests.
- Private Sellers: No inspection guarantee exists when buying from a private seller; you are responsible for any repairs.
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I bought it from a used car dealer in Pennsylvania and donāt remember signing a waiver. I do not believe the same law in PA exists. Thank you for the note though!
Drive the H E C K out of it for at least 1/2-hour or so before trying again is my quick suggestion before spending big bucks
Drive it hard in some lower gears for awhile
Find out when the testing station is open for business
Drive the car as suggested and make sure itās HOT
Be there idling BEFORE the testing station is open
Make sure youāre the first one to get smogged
Do this on a Tuesday or Wednesday
That way thereās less likelihood the car cools off while the tester is recalibrating equipment, performing some software update, etc
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I shut the engine off while waiting, I donāt want to fail the inspection for visible smoke. Old cars will sometimes begin to smoke if left idling for an extended period. Iām not going to replace the pistons and rings just to be able to idle the engine for long periods.
An OBDII inspection is a review of the vehicleās computer history, the engine does not need to be hot or cold for this to be performed.
Now that this vehicle has been identified as a smoking vehicle, you will be required to have it repaired before the next inspection can be performed. There is a possibility that the turbocharger is leaking oil into the exhaust system or the valve guide seals are leaking.