DanielP

Before I start I just want to say that I know theirs a bunch of these on the forum but none imo give a clear answer or have a clear question. So, my 97 Civic Dx (d16y7) blows smoke out of the tailpipe even when warmed up, at idle it doesn't much but when you rev it up to like 1,500k rpm it definitely leaves a cloud. I've looked at the smoke and im pretty sure its white, so I'm thinking coolant. How would I go about pin pointing the problem? Head gasket, valve stems or something like that?

mk378

If it's blue-gray oil smoke, this sounds like worn rings causing it to burn oil. How much oil are you losing?

A head gasket leak will quickly lead to overheating even if it isn't big enough to make noticeable "smoke". The smoke from a leaky head gasket smells like antifreeze, because that is what it is.

DanielP

I haven't had any overheating issues and I've been driving it for about a two weeks now, so does that mean it's burning oil? If it is that means I have to replace the piston rings right?

njn63

Blueish smoke is oil. White smoke is coolant. Coolant smells sweet when it burns vs a very pungent odor from oil.

The only likely place for coolant to enter the combustion chamber is a head gasket. Oil is generally either worn rings or valve stem seals.
(There are other places it could be coming from but those are the typical ones)

You can find information here or on google regarding how to diagnose/confirm which one has failed once you've narrowed down what is burning.

DanielP

Then it's probably oil because yesterday I got behind the tailpipe and started smelling and it smelled terrible. Say it is coolant though, what would happen if I didn't replace the headgasket for a month or two? Someone told me my rings would go bad. But I'm going to look into replacing the valve stem seals or rings. Would I have to do that now or can I wait a month or so because I don't have the funds to replace them right now and send off to a mechanic, and I need to drive it everyday for high school. I don't go above 25 mph everyday.

mk378

Make sure the radiator is staying full. Check it when the engine is cold before the first drive of the day.

If you don't have a cooling problem it's not the head gasket. When it is merely burning oil, you can drive indefinitely as long as you keep putting oil in.

DanielP

I checked my coolant level yesterday and it was almost to the brim of the cap, so it has to be a oil leak right?

DanielP

And come to think of it, I recently had a oil change, about 2 weeks ago? I checked the oil level yesterday when I got home from school and it's definitely gone down. I only drive a mile to school and a mile back.

mk378

Just keep an eye on the oil, add some whenever it gets down to the bottom mark, and you will be OK.

Don't use expensive oil, as your engine already needs replaced. Using a heavier oil like 10W40 may reduce the rate of burning some.

DanielP

Why do I have to replace my engine, don't I just replace the valve stem seals, or pistons?

DanielP

Bump, why would I have to replace the engine?

civic402lx

Because it may be cheaper then fixing it. Have u done a compression test to see how healthy it is or not?
blown that much white smoke, if headgasket is bad, the head and block may be warped. Ever had overheating issue?

DanielP

Nope, never had a overheating issue, just the smoke even when it's warm. I have a friend that has a compression tester, I'll try and compression test it this weekend. What should all the cylinders be at?

mk378

More than 130 psi in all cylinders. Less than 25 psi difference between the highest and the lowest one.

It is very important to cut the power to the distributor by unplugging the harness wires before cranking the engine for a compression test. The coil can be damaged by firing with the spark plugs disconnected.

civic402lx

Go to YouTube. Search for ericthecarguy how to do compression test. Watch and repeat.

DanielP

Gotchya, thanks for the info you two, really appreciate it.