1999 Montero Sport 3.5 V6 automatic with 185,000 miles white smoke. (I searched, and looked through 10 years of posts.)

This Montero runs fine, has good power, the oil is clean, the radiator always stays full, but it has an intermittent white exhaust smoke issue. I don't think it could be a head gasket.

It seems to be water, steamy white and drips out the exhaust. But the radiator is always full.

This is my wife's daily driver, and she says people are pointing at her and getting upset.

We know the catalytic converter probably needs to be replaced, because we were told so when we bought the car a few years ago. Could that be it?

Or I am thinking maybe valve stem seals? but that wouldn't make such white smoke.

It uses oil, but no giant drips, but that is not the issue for today.

So if the white smoke is not caused by a blown head gasket, what else might it be? There was a post about PCV valve, maybe that?

Any thoughts? thanks.

 

It is easy to mistake the light blue smoke for the white smoke. Having water dripping out of exhaust is normal and is not in itself a sign of problems. If the coolant level stays steady and you do not have to top off the radiator - it is probably not a head gasket. At the same time, you indicate that it uses oil. How much and how often you have to add it? The issue with valve seals is more likely.

 

Prob 1 quart per 1000 mi, or about half a quart every time I think of it.

 

It might be valve seals. If you can, drive behind the vehicle in another car so that you can see if there is a pattern to the puffs of smoke. That may give you some clues as to where the oil loss is happening. For example, if it happens only after you idle at a traffic light for some time or after vehicle sits for long time and restarted, it can be valve seals. If on the other hand it happens a little all the time or only after hard acceleration, it likely to be rings. You can also do a compression test to check if valves or rings are bad.

 

OK, thanks. I will follow this weekend and report back. We have mostly noticed smoke after long periods of idling. My wife will pull off the road and talk on her cell phone for 20 minutes with the AC on. Then it really smokes !

So, if indeed it is valve seals, can I do that while still in the car with that air compressor trick? Or should I pull the heads and take to machine shop.

Can I even GET to the heads while the engine is in the car?

I have sort-of heard about pump them up with air, but I don't know the exact procedure, or if I have the right tools?

 

Yes you can do valve seals replacement with the heads on the car. It does require some specialized tools, but if you have some experience you should be able to to do it. Do some more reading and make sure you understand what you have to do BEFORE you turn a single nut. You don't want to take something apart and not know how to put it back together. The job does involve removing the timing belt. So, if you are not comfortable with that job - do not attempt.

 

valve stem seals i have and rent out the tool to do them on the car if you want to tackle the job

 

Yes. I would like to follow up with you. Thanks