So I'm hopeing someone could help me out. I have a 1996 lexus ls400 and i love it but im having some issues. I have white smoke pouring out the exhuast with horrible gas smell also is running rough (misfiring). someone said bad Head geasket but no mix in coolant or oil and levels are good. Sparks and wires r good. someone said ECU and i hope there rite wat do u think? any test u kno of to pinpoint? thanks

 

is the check engine light on? their are a number of reasons and im no expert however it sounds like a vacuum leak, things to look at : pcv valve, air filter, distributes, fuel filter, egr vacuum filter.

 

yes the check engine light is on. and the air filter is dirty but i cleaned it but still no change. And im not to familiar wit the enigine so where are those things located at??

 

can i ask did you run a scan tool yet???? i highly doubt its the ecu itself!!!! i would have to agree with kuziwk and check the pcv valve, air filter, fuel filter, and the egr system. could be possible your cap and rotors might be bad also.

 

Well i did run the test and codes i got were p0136 (02 sensor), p0156 (02 sensor), p0110 (IAT???), p0300 (random cylinder misfire), p0306 (cylinder 6 misfire), p308 (cylinder 8 misfire). They didnt help me out to much because i already knew the 02 sensors were bad and the cylinders were misfiring but i dnt know why. mabe the p0110 is the key? i dont know exactly what it is though.

 

well than you have your work cut out for you, replace or clean the defective o2 sensors, than do your dist caps. Also how do you know the wires are good, did you physically take a multimeter and check the resistance. There are tune up kits on ebay which come with plugs, wires, and dist caps start from there. Also how can you clean an air filter unless its a K&N? If all else fails grab an ecu from a junkyard or ebay.

 

Well i did the spray water test on the wires and they were good and wen it first started messin up i took it to mechanic and they checked the spark plugs they were good. but im going to try and find all the stuff u said and try and clean those things. my biggest problem is i'm not sure where everything is. thanks man i appritiate it.

 

Did you ever get the issue worked out?