deanbrown

96 LS w/220K miles - some valve 'chatter' when pushing the gas pedal. Does this indicate an upcoming failure or valve job? Or just an adjustment (valve clearances?)

Been like this for a year or two, but gradually getting louder. Never had any engine work, and always used mobil1 synth every 5K miles.

LiCelsior

iTrader: (32)

just needs an adjustment..pretty common with teh 1uz.

deanbrown

So is this something that people do themselves? Any special tools? As far as I know it's never been done, at least in the latest 150K miles.

CrashGT007

Does it sound like metal to metal or does it kind of sound like a sort of flapping. Because the lower egr pipe is notorious for getting a crack in it. I thought it was a valve problem at first. Check under the hood and listen at the back of the intake for a flap/tapping noise when you pull the throttle a little it then thats it...

Carnut

Could it be he needs to up his octane a bit to mid level, if he's not already using it. My '93 LS-400 used to sound like the engine was coming apart if it sat for a few days. Some Lexus Tech friends of mine told me to go to a GM dealership and get some "Upper Engine Cleaner", remove the vacuum hose from the power brake booster, and pour the entire can into the hose with the engine at a slightly high idle and then let it bog down and die. Let it set for a few hours, if not overnight, and that would clean the excess carbon buildup off the valves. Worked for me. I had 148,00 miles on my LS when I did that.

Just an idea.

deanbrown

Yes, that is what it sounds like. I hear it when stationary and when driving I was going to take the cover off today and take a closer look, but then I had to do the $&^#%$ 5 tons of leaves in the yard.

Is the egr pipe visible / can you feel it blowing when you just take off the cover? sounds like something is blowing.

deanbrown

That would be SeaFoam? I've put that through a land rover before a couple of time - do people do this to their LS's too around here? Any problem with the O2 sensors?

CrashGT007

No the pipe is not where you can completely see it its connected from the passenger exhaust manifold to the back of the engine. the best way to get to it is to put it up in the air and use a swivel to get the bolts... its a pain you hav to snake it out. i could only find the piece at the dealer... and there are two of them back there. the one that fails the most is the bottom one which flexes more.