Blogs Car Info Our Show Deals Mechanics Files Vehicle Donation

2002 Highlander. Puff of blue smoke on most startups

150,000 No loss of power. Only very small loss of oil in 3000 miles. Could it be valve seals. At what point is this a fix it problem. Would like to run car as long as possible. Great car. I had valve seals replaced years ago in a Chevy 305. That was so bad that I needed a stand off plug to prevent fouling and skipping. Should I look to trade or will the fix not be too bad. NEED advice!!! Thanks

I had this happen with my '96 ES300 (same basic engine), it seems like the valve seals are the common cause for this. I just keep track of the oil consumption, it’s very low, so there’s no way I’d spend the money to fix it. It takes very little oil to cause the puff on startup.

It probably is valve seals, but I would first pull the valve covers (you have to to get to the valve seals anyway) and check for proper drainage. Some oils, if left too long in the engine can form sludge along the top of the head and clog up the drain back holes.

This engine may also have a dam under the camshaft so that the cam is always bathed in oil, even on startup. You need to be sure that there isn’t sludge on top of the dam so that the oil level under the valve cover can rise up to the calve stem seals, even good seals will leak if drowning in oil.

This is a normal consequence of aging valve seals. The oil that lubricates your valvetrain runs down return channels and back into your oil pan. What happens is that when the car is parked overnight, some of this oil, which normally is blocked from passage into the cylinders by the valve stem seals, seeps past worn seals onto the backs of the valves. If the valve is resting in the open position, it can even drip into the cylinder. When you start the engine in the morning, it gets burned. You won’t see it in small amounts, but it’s probably getting drawn into the cylinders on deceleration when the cylinder vacuum spikes too,

With a small loss, I’d just consider it normal and monitor the oil level. Some might argue that it may reduce cat converter life by putting some additional burned oil onto the surface of the converter’s platinum-palladium coating, but my feeling is that on a vehicle with 150K a tiny amount it isn’t a big contributor.

In short, I agree with Texases, as I usually do.

And I congratulate you on monitoring the condition of your engine and pursuing anything you’re uncertain about. Keep up the good work.

Good call Tex,this problem used to be prevelant on Fords-Kevin(mostly harmless)

Are there any additives that help open blocked back drain holes or clear dam under the cam shaft? LIke Miracle oil. Thanks for the comments!!

If you’re not burning oil, and you’re changing it adequately, I wouldn’t put anything else in your oil.

How many miles between having to add a quart?

How many miles between oil changes?

I agree with Tex. What you’re experiencing is perfectly normal and poses no danger of causing more problems, and additives are always a gamble. They’re worth using to try to squeeze and extra year out of an old beater, but not on a well running engine.

Puff of blue smoke at startup is usually valve seals. Nothing to worry about. They do wear over time. Both my Pathfinder did this after about 8 years and 260k miles. Both lasted at least another 100k miles. My 98 Pathfinder over 150k more miles…and still going.

Blue smoke while you’re running…that’s a different problem. Usually rings…and you’ll need a new engine.

Agree, no additives. I also agree that with the rate of consumption you have right now, I wouldn’t do anything. Anything you do right now will cost you a lot more than just checking and topping off the oil.

I will add that if you feel you MUST do something, the correct thing to do is to have the valve stem seals replaced.

While I still feel it’s unnecessary, I can understand having it done for peace of mind. If it helps you sleep better, it’s worth it for that reason alone.