Good afternoon,

I need help trying to figure out which exhaust gasket I need to replace n my 1991 Lexus LS 400. I tried exhaust tape to get me going but the pressure from the exhaust blew off the tape. That was the dumbest thing to do but anyway it's Friday and I wanted to go out and buy the gasket(s) to resolve my exhaust leak issue. Problem is I am not sure of the part name and was wondering if someone could help me.

It seems as if the exhaust leak is coming from the front of the car on both sides driver and passenger side right before the oxygen sensor. If I am not mistaken, that would be the catalytic gasket?

Please help.

Thanks!

yep that would be the catalyst converter gasket...but on the header side or the mid pipe side is the question.

I believe it is the mid pipe because I tried to patch the gap, it seems as if the gaskets fell out or the previous owner toke them out and didn't completely tighten the bolts. I remember that when I tried to patch the gap with metal tape, I kept banging my hand on the oxygen sensor. How much would it cost to replace the gaskets (parts and labor)?

parts are relatively cheap, labor im not sure...keep in mind u might need new studs/bolts also.

labor with a good impact wrench and some PB Blaster is cake. i replaced mine two weeks ago

Sweet idea. I check and my bolts are rusted to the bone...

Cool... I will do so. Do I order them from the dealership or could I just go to Home Depot to buy some bolts that will fit them?

Thanks!

Is there suppose to be a gap in the middle where the cat and exhaust pipe meets?

http://www.sewellpartsonline.com/

has cheap OEM parts. call them and they'll help you out..they also have a coupon code, clublexus

What have you guys' exhaust leaks sounded like? Does it sounds kind of like a hissing noise or a loud ticking? My car is making a hissing noise underneath and it goes away at idle but starts hissing just above idle. It's coming from under the car.

I second the PB blaster suggestions, make sure you let that stuff sit overnight on the bolts and you'll have a much easier time in the morning!

YOU need to check your EGR tube also, that is the way mine sounded.. you can take a 2 foot piece of vacuum hose and slide it down behind the engine and you can pick up the sound very quickly,,

good luck..

my favorite method is to seafoam the car, then while it's still smoking hunt around with a flashlight for smoke

Forgot about the infamous EGR tube. I've read two different theories regarding replacing it. I've mostly heard that the transmission must be removed but I've also heard that it can be done without removing the trans. Which way did you do yours?

mine was the 97LS, removed the passenger side cat/converter, and lowered the rear crossmember and let the motor sag to get to the bolts.
BUT mine was the two piece EGR, I think the 1stgen has a one piece.
good luck..

sorry banshee, got you mixed up with britton