my 97 ls400 revs low when i approach a light or have to slow down, the revs go so low almost to the zero then before it stalls it shoots up again, i just wanna knw whats going on, and why it does that, the check engine light was on so i put the computer on it and the code was for the egr valve, i got a new one and it still does the same thing, i was thinking its the spark plugs but I'm not sure

 

Cleaning the throttle body MIGHT help but maybe a tune up is in order. Check the plugs to see what they look like.

 

ok will do thanks! i was thinking of doing that

 

Yes... cleaning the throttle body and swapping out the plugs worked on my old 95... it would get so low that it would die coming off the interstate...

 

ill try that because it does fine on the freeway, it just happens when i press the brake when i come to a stop or a light

 

so today i cleaned the throttle body and it was filthy!!!! it was so bad i cleaned out the whole intake manifold and it was filthy, so i put every thing back on and it still does the same thing, now the next thing I'm going to do is the spark plugs, wires , cap and rotor, hopefully that fixes it, but if its not that then who knows what it cud be

 

did you clear the EGR code? low revs is typical and usually a TB cleaning brings it back up. there is also an idle control valve that gets gunked up.

http://www.planetsoarer.com/IAC/iac.htm

referenced from:
https://www.clublexus.com/forums/per...rol-valve.html

 

no i did not clear the code, and that part on ur link, thats the part i replaced for a new one, i did clean the throttle body, i also cleaned the whole intake manifold

 

https://www.facebook.com/photo.php?f...type=1&theater
so i cleaned all that and it still acts the same

 

That's a lot of oil and it's most likely your PCV.

 

it looks like that because of the carburetor cleaner, whats the pvc?????

 

There's more to an EGR system than just the valve. Clear the code. If it comes back, you haven't solved your EGR problem.

 

lets say it comes back, what is another way i can solve the egr problem? my check engine light came one like 2 3 weeks ago so i checked the codes, it came up with 2, 1 was the egr, 2 was my catalytic converter, i checked the egr, it looked bad, so i ordered the part, by the time i got it in the mail, the check engine light had came off by it self, i took it to get it smogged and the code still came up even tho the check engine light was off, they did not erase the code, and i just put the new egr the day after

 

PCV= Positive Crankcase Ventilation Valve.

 

a friend that works at toyota told me it was probably going to the idle air control valve