qewani1

Am going to seafoam my LS400 with one can of seafoam.

I don't know if what am going to do is either right or wrong!!

Can you guys help with the steps of seafoaming.

i have searched around the forum and found that we have to put

- 1/3 in fuel tank
- 1/3 in engine
- 1/3 in brake booster hose.

Turn car off for around 15 minutes and then start the car and enjoy with the smoke show.
oh and also must replace engine oil/filter after the seafoam.

Is that correct or i missed something?

qewani1

any help?!

fatcat2

if you go to sea foam engine treatment page it explains it all. go to the faq's and you will see. but you are right from what i have read.

RA40

iTrader: (6)

What motivates you to Seafoam? What type of issues does the car have?

qewani1

I get low MPG on highways; I get maximum like 17-20 MPG
Already tried most of solutions from what I have searched/founded in the forum and I just want to clean the car engine/fuel system/spark plugs/injectors/manifold from inside from any carbon build ups, so I may get better boost drive + better MPG , who knows it may improve MPG !

Recently I had even replaced the old engine of my ride which has (270000 miles) on it with low mileage (7000 miles) engine; it was imported from Japan… but still no improvement in MPG.

Car runs great + with no CEL + already tried almost everything.
People recommending trying sea foam to improve car performance and MPG. Is that wrong!? I just want to try this? Nothing to lose!

qewani1

I already searched in youtube/forums/google.

Am just waiting for the green light from you guys!

Did I mess something or should i go ahead and start the sea foam?

RA40

iTrader: (6)

If both engines are giving these symptoms, there is likely another cause. I doubt Seafoam is going to remedy it. You did the coolant temp and O2 sensors? What grade gas are you filling it with?

denverdog

when you suck the 1/3 of the can into a vacuum line, that will cause the car to die. you don't have to turn it off. when it dies, let it sit for 15 minutes before starting it back up.

willhickey

iTrader: (1)

garbage gas?

qewani1

I always fill tank with 95 octane gas.
Did not try to change to coolant temp sensor yet. BTW I saw the ECT thread which was posted in the forum.

Have checked O2 sensor reading using OBD2 device on idle during closed loop and open loop. Since am not getting any CEL, am assuming that O2 sensors are performing fine. I can post O2 sensor graphs readings if you can help with diagnosing the O2 sensor readings!!!

Since (O2 + ECT) sensors cost some cash am just trying to start using the cheapest methods first to improve the MPG. O2 and ECT are in my pending list.

qewani1

Thanks.

Imperium11

if a few sensors are going to break the bank maybe replacing the motor before actually trying to find a problem with the old one wasnt the best and most cost effective idea ?

python

iTrader: (4)

not neccessarily true...did the new engine come with everything? did u have to swap any parts over ...ill bet u did, i think the whole harness to the engine is different.
02 sensors are supposed to be replaced at 100,000 miles...it doesnt matter if u have a check engine light on or not

RA40

iTrader: (6)

Does your car have the catalytic converters on it? Air filter clean? A car with 270K miles has a good amount on it. I feel for you, hunting down problems is a challenge.

qewani1

Done the seafoam, and still same poor MPG.. Going to diagnose o2 sensors now.