monkiwrnch

iTrader: (1)

hello everyone! i have a 93 gs300 with 118.xxx miles on it,pretty much stock with an k&n Air filter and a Raizer jdm Aftermarket exhust. my problem is white smoke is coming out of my exhaust. and it ildes kinda rough when its happening, and it does it intermittently, my coolant level dosent seem to go down and the smell of the exhaust isnt really sweet smell like a burning coolant does. but i can hear a bubbling noise from my resevoir tank. i thought ive fixed this problem before. 4 months ago when i first notice this problem, i check the car and found out that my #6 spark plug had a small crack on the ceramic tip,((((this is a new set of toyota plugs too! about 8-9months old))))) causing it to misfire and run rich on that cylinder. thus the misfire/white smoke and hesitation on idle. but after i replaced the spark plug it was gone. then 2 months later it came back so i check all my plugs again and found out that no# 5 plug has a crack this time.so i replace that one, but the misfire and the white smoke coming out of my exhaust didnt disappear,i havent checked my injectors yet if all of them are firing when the problem is happening... if its the head gasket problem how come its very intermittent??? and why did both spark plug that are next to each other are the culprit( could be a head gasket problem!!! i hope not) i did a coolant pressure check and its holding pressure, im so confuse on this one. ... hope some one could help me on this one! thanks!!!

GS300916

milky oil cap? im assuming not?

white smoke is intermittent? while driving or idle? or only in the morning?

How about check engine lights?

monkiwrnch

iTrader: (1)

No. Milky oil cap, no codes (this what confuse me the most). It does it more when its at idle ut I can feel it sometimes to when driving.

Triple C

iTrader: (2)

So this happened to me....
The VCV (Vacuum Control Valve) coming from the powersteering Vacuum line connects to the Intake. If this valve is broken it will pull small amounts of Powersteering Fluid into the intake and burning off as white and sometimes Bluish smoke.
Just something to check out since it sounds like you have a handle on the obvious things.

monkiwrnch

iTrader: (1)

thanks for the input GS300916 and Triple c, ive check my car today,i did a coolant pressure test on it again and waited about 20mins, and when i started the car it started smoking again, i think i have a slow leak on my head gasket. and found out that i have a leaking injector too. cause my buddy hooked it up in the Smog machine and my Hydro Carbon (Hc) is really high. its running so rich that the white smoke dosent smell like burning coolant but a really rich fuel mixture smell. i guess it makes it really worst with coolant and unburn fuel at the same time. so thats my dilemma right now. i dont know if i should just replace the head gasket with factory one or put a stronger gasket,head bolts,machine the heads and install a turbo on it. or just go 2jzte, i dont know what to do.

thanks once again for those who chime in!!!

Triple C

iTrader: (2)

Did you do a Pressure Leak down test to see if you have a lot of loss. This would tell you if you had a blown gasket

monkiwrnch

iTrader: (1)

i havent done a cylinder leak down test yet, but im 99.9% positive that i have a blown head gasket. but ill make sure and do that test before i start to tear it down.

rapril

I have an LS400 and spent almost $3000 on completely useless and unneeded repairs. I had a pressure test, was told I had a blown engine, blown head gaskets, and a plethera of other things. Come to find out, could have spent $300 on a new engine computer (ECU). The guy that was a "foreign car expert" had no idea Lexus's are known to have these problems (Quote from mechanic: ecu can't cause white smoke, he was wrong) so just a suggestion to check that because it's cheap to check and at least mark off your list. If you search it in the forums here like I did, it'll give you a list of symptoms.. Not sure if it could be it, but at least thought I'd tell you my bad and very expensive experience Have a great day

bigjoeoso

this is literally what im doing tjos week tare down and replacing my head gasket cuz i have all the same symptems and the high (Hc) i got just the stock gasket from O'Riellys out by my house... well the whole gasket set it comes with water pump gasket and all intak and exaust and valve cover to i just need to know if i need new head bolts or not you know i have a small budget and just happed to run in to a guy that has a shop and he said that he would machein my head for 25 bucks... woot woot then im slaming it while i wait for the head to get back

ClarkKent

Head bolts stretch. Must replace them.

Titten

It's too big a big job to half *** it, if you're like me, you want to drive the thing, you don't want have to do it again. $25 doesn't cover new valve seals, guides, pressure testing it, does it? And absolutely, use new a Toyota head bolts properly torqued in the right, stepped sequence. I forget the correct head bolt torque spec. Be ready to replace old, small hoses and keep eye out for old brittle connectors and other unplanned stuff. GL.