Blue smoke from tail pipe?

[Jason]

Hey guys. So it seems my car is starting to have more problems than I knew about. One of the senior mechanics at the oil change place I work at informed me he saw some blue smoke from my tail pipes when I took off heading out to lunch. Pressing him for info, he said there’s a possibility that my rings might be bad. I have a 1993 Honda prelude Vtec. I haven’t done any tests on her yet or anything. At this point I am still trying to gather info on what I need to do to diagnose it and find if its the rings or what the real problem is if its not. What kinds of tests should I be doing and what should I be looking for?

Also what are my worst and best case senarios and about how hard would these be to do on your own instead of taking it to a shop? I’m kinda limited on money, so trying to figure this all out without breaking the bank but also not cheap out on things.

Topic

[Its me]

Smoke from the tailpipe at initial startup in the morning (or after it has been sitting) is indicative of oil leaks through the valve guides/valve seals…

If it is continuous on a warm running engine, it more than likely is indicative of rings going bad… Which means at minimum, a partial rebuild (new rings and deglaze the cylinders)… This can escalate quickly to new pistons and new bearings and much more…

After all, it is a 21 year old car…. so it is not surprising…

If money/repair is an issue then continue to operate the car and watch the oil level closely… You can continue to operate, but you must ensure it always has a proper oil level…

-Karl

[Lorrin Barth]

Does the engine use oil?

[Jamie]

Its old so something’s are bound to start leaking or bung up. Mentioned above is 100% correct about start up, or while running.

I found in a lot of older cars its a gunk issue as well as wear. All though it wont make your engine new again using a good oil system cleaner will help clear up blocked and stuck oil control rings. You can go a step further and let the car sit over night with a little bit of it dribbled into each cylinder can help free up stuck rings.

If its burning on start up there is only really one way to fix it and that’s to replace the seal. But you can using additives designed to help old engines. Its probably the best use of Lucas to be honest.

[EricTheCarGuy]

Honda 4 cylinders burn oil. It’s just a fact of life. That said, some burn more than others. Everyone hopes for valve seal problems but the truth is, this is not often the cause. Extended oil change intervals can cause the oil control rings to load up with gunk and they don’t work properly. When this happens, the engine burns more oil. Thing is, if you’re going to go in and clean all that gunk up, you might as well do a rebuild or replace the engine. You can cross your fingers and dump some ‘product’ into the oil and hope for the best, but thats a long shot in my experience. If you’re not experienced in engine building, I’d recommend replacement. I’m not saying that’s what you have to do. If you’re passing emissions, or you don’t have to worry about them, don’t worry about it. Drive the car and get on with your life. More info on burning oil in this article I wrote.

http://www.ericthecarguy.com/faq/finding-and-fixing-fluid-leaks

Good luck and keep us posted.

[Bill]

First thing to do is make sure the oil is on the full mark. Mark down your mileage and keep it in a place where you are gonna remember where it is. Drive the car normally and keep an eye on the oil level. If it drops to the add mark before it’s due for a change. check the mileage to see how far you drove on 1 quart.

If it’s 1000 miles or less then you have a problem. If it’s 1500 to 2000 miles then I would say that is normal for an older Honda like yours.

[Jason]

Thanks for the response guys. The odd thing is, I replaced the motor at 250k with a used crate motor. H22a, the J-spec motor. It “shouldn’t” be that old. It was said to have 30k -90k on the motor when I got it, plus putting another 50k on it myself. As for how reliable that is, I can’t verify.

But yes, the blue smoke was seen while the engine was warm and running. I don’t see it myself from the drivers seat, and it’s not some huge cloud, just a tiny puff. The other indicator is I have a lot of black soot built up on the back bumper above the tail pipe.

[EricTheCarGuy]

The black soot is also normal for that engine. The fact that the engine was used means that it was already worn before you got it and who knows how it was taken care of. As I stated, Honda engines can burn oil, even when new. Any wear on them can make the problem more pronounced. Also, given that your engine could be considered a ‘performance’ engine, I would say that it’s likely been driven in a spirited manner. This can increase cylinder pressure and cause it to burn more oil. On the flip side, if it wasn’t well maintained, there could be buildup on the pistons blocking the oil return holes which can also cause blue smoke out of the tailpipe.

In summary, it’s likely an internal engine issue you can do nothing about. With that in mind, drive it until there’s a real problem. It may be some time in the future before that’s an issue. Otherwise, look for a new engine, preferably a rebuild with a warranty.

[Author]

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