Synthetic oil didn't cause your problem.

Unfortunately dumping Seafoam probably did some damage. I am going to guess like you did that it did the valve seals.

The P0430 is a bank 2 cat problem. More than likely the sensor on catalytic converter is fouled since you just did the change but it could be a fouled cat.

How exactly did you Seafoam the engine?

 

Seafoam - my thinking as well. I've been running synth blend for awhile in my Camry, never an issue. In my prior car I went full synthetic, never an issue.

 

Its a common occurrence to see initial oil consumption when changing from conventional to synthetic. The cylinder walls are coated with years of conventional oil glaze. Takes a while for that to be replaced. 5-10k things should get back to normal or close to it.

Your right, synthetic oil does a better job with flow and lubrication. So if there is engine wear at the rings or valve seal, anywhere oil can seep, the synthetic oil would surely find it.

Seafoam will give you a cat code if you use too much of it in the gas. Because its mostly pale oil, a lube that does not burn off the cat very well. Will oil it up and contaminate it, lowering its efficiency. But in most cases especially Toyotas, you were burning oil in some amounts for a long time. Just more noticeable right now. In the oil being a thin lube, Seafoam will make your oil thinner, maybe coat the cylinder walls for a while preventing a new oil glaze. That will go away after a while.

If after a second synthetic oil change/10k the oil consumption hasn't gone down, try what I use in the old camry in my signature. Perhaps a little thicker. as stated above, could be leaky valve seals.

 

OP has a 3MZFE V6 which isn't known for any oil consumption issues.

Also I have switched plenty of high mileage cars from conventional to synthetic and never ever experienced an issue. Especially something like start up smoking.

105K isn't even a lot.

 

Thanks for the replies. So should I go back to a conventional oil since that is what I was using all along? I can't believe the seafoam might have done this. I've never used any additives in my engine until this one was recommended. If it continues to smoke on start up, is there anything I can do to maybe help condition the valve seals, short of having to pull the head and getting them replaced?

Also, you guys were saying that P0430 fault code is a bank 2 cat problem, possibly a fouled sensor on catalytic converter. I've read that there is more than one sensor since its a V6. How do I know which one it is and is it possible to test the sensor before replacing it? Thanks again.

 

The sensor code isn't important and you have more important problems at hand.

Does it smoke all the time or only at startup?

What oil did you use?

 

The type of oil was
Valvoline/Durablend synthetic engine oil SAE 5W-20



The smoke is only at start up and it has subsided some. Maybe using the seafoam cleaned all the build up off the engine and its taking a while for the engine to adjust to the synthetic oil? I've had my wife follow me in our other car and she said there was no smoke while I'm driving the car on the highway. It seems to only happen when the car has been sitting all night and I start it up in the morning is when I'm getting blue smoke.

It just seems like the car is bogging down and not getting great mileage. That's why I'm really concerned about this whole P0430 sensor thing. Could the burning oil have caused it to fail? Thanks.

 

Toyota has a big problem with cat. efficiency below threshold codes-P0420, and P0430. Go to the dealer with that code and they replace everything. Cats, before and after cat sensors. they don't know how to fix it. It is hard to diagnose. A lazy sensor can cause it, and not test bad otherwise. Some models have had TSB's issued to reflash or replace the ECMs in an attempt to fix problem. Supposedly converters don't just fail unless contaminated or damaged. I feel that ethanol blend fuels are contributing to the problem. I think that the parameters the ECM uses to set those codes are in error. Try replacing the downstream (after cat) Os sensor first. As for the oil consumption, 5000 between changes on conventional oil is too much-no mater what Toyota says. Give it a little time and see if smoking, oil use with the synthetic slows.

 

Really hoping I don't have to go that route and replace everything. I've been pricing these sensors and they can get quite expensive. So you're suggesting with the trouble code P0430 which is a bank 2 cat problem, replace the downstream (after cat) OS sensor first? Is that the same as downstream rear? Some auto parts sites have them listed as "downstream front and downstream rear" Thanks

 

Use Denso, not Bosch.

 

I have read a lot re folks using Seafoam ...on perfectly good running engines ...what's with that? Is there any INDEPENDENT analysis out there showing this to be safe, smart or to enhance or improve something? Sheesh ... Toy engines, with even poor care seem to last a LONG time ...

Now this all said, my son's 1999 4 cylinder had massive amounts of coking buildup on every surface inside valve cover and on head, cam bank, etc ...chipped it off with various surgical implements while vacuuming at same time ...don't think magic stuff would have helped there ...better oil and more oil changes would have.

Reminds me of the Water Wetter additive some folks use ...supposed to improve cooling ...instructions said to decrease amount of coolant to water and add water wetter ...duh ...likely improved cooling because had higher percentage of water ...

Anyone know of any independent Seafoam analyses?

 

Anyone know of any independent Seafoam analyses?

all i can find thus far, is message boards where there is a split in the belief this crap works.

some say when a person uses it, he thinks it works, because he spent money on it.

some say it is nothing more than a "placebo"......

but what i did read, is where you are indeed putting oil in the gas tank, mucking up the cat.

seems like many advise against using it, and rather use Techron, Red Line LS-1, Gumout Regane, and 3M.....3M what...it doesn't say.

 

If the code doesn't present a problem with emission testing then you could reset the code wait for the oil problem to stabilize. If sensors were coated, making them less sensitive,
it could burn off eventually. Wouldn't change sensors or cat now while you still have an oil burning problem.

 

Wow, drive it for 10,000 miles to see if makes any difference? I gotta be honest guys, I only average about 10,000 miles a year on this car now. It's a daily driver, but my commute to work is not that far, about 20 miles round trip average, along with running errands, kids to school functions, etc.

I'm still having to top it off with about a 1/2 quart a week now. And it seems to burn more blue smoke at start up when the oil level is where it should be. I'm not overfilling it and have monitored the oil level on a weekly basis.

Would adding a quart of the additives on the market like Duralube or Slick 50 help slow the consumption? From the responses I've read, my piston oil rings my be gummed up or clogged. leading the burning, would these additives or something else possibly help? Thanks again. Mike

 

So if you drive 20 miles a day for 5-7 days a week you only do around 100-150 miles a week. That's 1 quart every 200-300 miles which is HORRIBLE consumption.

I can guarantee you synthetic oil is not your problem, especially on a 3MZFE. Heck I switched a Lexus ES to synthetic at 130K and it runs like new. I switched a V6 Solara over even later.

My guess is the oil flush caused a serious problem. You have to figure out where your leak is coming from. Is it valve seals, broken ring, PCV valve issue, or something else.

Unfortunately it's a guess at this point. Does it run normally at least?

 

I agree, it's got me extremely frustrated too.
Yes Hardtopte, It's been running fairly normal. I have noticed it's a bit hesitant on acceleration, but I was attributing that to the malfunctioning oxygen sensor (P0430 code) Starts up just fine, with the exception of the blue smoke. There aren't any leaks anywhere. Does this model engine have a replaceable PVC valve? I couldn't locate one.

 

Yes the PCV valve is located on the rear bank valve cover near the passenger side strut tower.

Only use a Toyota PCV valve.

Part #s

PCV Valve: 12204-20060
Hose (if damaged): 12261-20091

 

Also lets try another oil change with a good oil like Pennzoil Platinum and an oversized PL20195 oil filter (FL400S Motorcraft as well).

It is a wild guess, but maybe something in there is causing the problem.

 

Will do. Is Pennzoil Platinum a synthetic? Should I stick with a synthetic or go back to conventional like I was using? What about Mobil 1, I've read on here that it's a great oil, do you recommend it? I've been using NAPA Gold filters. The FL400S Motorcraft is an oversized filter and will work with my camry? I'll go ahead and replace the PVC valve too. Thanks again for the help.

 

... as reported by Zero260:
Seafoam's main contents are #1 ACETONE (High purity) and #2 TOLUENE, a Benzene family aromatic compound with octane rating of 115 KI (knock Index), Toluene is a carcinogen and requires special handling i.e. (gloves, mask, clothing) and lots of ventilation, not to mention it's high flammablity :thumbsup:

So, it looks like there was some significant solvent action going on within the engine oil passages. Apparently, a single oil change was not sufficient to clean the resulting debris and remnants of the resulting cleaning mixture. ... As mentioned previously, the valve seals could be compromised somehow, as well as exhaust sensors and the catalytic converter.

 

... as reported by Zero260:
Seafoam's main contents are #1 ACETONE (High purity) and #2 TOLUENE, a Benzene family aromatic compound with octane rating of 115 KI (knock Index), Toluene is a carcinogen and requires special handling i.e. (gloves, mask, clothing) and lots of ventilation, not to mention it's high flammablity :thumbsup:

So, it looks like there was some significant solvent action going on within the engine oil passages. Apparently, a single oil change was not sufficient to clean the resulting debris and remnants of the resulting cleaning mixture. ... As mentioned previously, the valve seals could be compromised somehow, as well as exhaust sensors and the catalytic converter.

Geez, No the kinda news I wanted to hear. I still can't believe I took some autoparts stores advice and used that stuff! I've never used any additive or cleaners in my engines (until now) and I'm starting to regret it. I was told it wouldn't harm my engine or sensors, but I really believe it definitely had something to do with it. I bought this car brand new and have never had a single problem until now. Pushy sales people and their gimmicks! I should have just stuck with what had worked for me for many years.

 

Always astonishing to hear of someone taking 10 seconds of advice at an auto parts store from an unknown person ...unknown skills...unknown education ...unknown experience - when the internet exists.

And then acting on what is considered to be the second most important asset they own.

Anyone else find this odd?

 

+1
I know two very good mechanics and both of them had advised me to stay away from the Sea Foam when I bought a 2000 100k Camry and was planning to use it to clean the engine. I switched to 5-30 High Mileage synthetic oil, replaced the spark plugs and belts and had no issues for 40+K.

OP, switch to a thicker High Mileage full synthetic oil, it should take care of smoking and oil burning.