lorenzo816

1992 LS400 170k

Car never gave any warning. It just started sputtering the last few miles home, like it was missing a cylinder or arcing or something. Or kind of like transmission is acting up.

Happened before in my other vehicle;

so I changed the plugs (NGK), wires are on the way.....

Now it still is not getting good power when I hit the gas.

Sputters the engine even in neutral. Sputters in drive - any gear......
It just conks down when you touch the gas, and any hill you try to drive over sucks big time.
Never went out on me, never died that is......on the way home.
But I was "that guy" for about an hour.

It Doesn't get hot.
Doesn't Rev high like a bad tranny....
Isn't leaking anything.
Isn't eating gas.
No codes coming up.
Lights aren't getting dim.
Connection to battery is good.
Power steering pump soon to be replaced, but alternator is in good shape.
Timing belts are on and look great.


Loud hissing coming from the front top of engine, Mild-hot air is coming out of it, (exhaust?)
Exhaust pipes smell a little funny - not rich though. Not burning oil either.
Tapping, sort of like low oil, occurring on the driver's side of engine.
Oil is full. Transmission fluid is clean and full.

Left Cat is starting to popcorn.

Could the Cat be clogged and have blown out a manifold or gasket up top?

HELP PLEASE.

I have a CD manual so I can find all the goodies if people HELP me..... Pease

lorenzo816

I Found a small hose near the regulator that was loose. Put sealant on it and got it back on tight.

Still a loud hissing noise coming from the bottom. Stinks bad, like carbon......

Exhaust Leak

Both of the flange connectors behind the cats were leaking badly.
Didn't I just have those gaskets replaced? Anyways....

Going to fix those gaskets and also find out if my convertors are bad tomorrow...

any other ideas are requested.....

anyone?

lorenzo816

Alright,
reason for the hoses blowing off and gaskets blowing out, was because the y-pipe is clogged.

mech said that there is a screen between the manifold and the cat, and that I'm missing one on one side and has contributed to the degradation of my cats and clogged the y-pipe. (likely story - I'll see for myself)

cats - around $900 each
y-pipe - around $1850

Any other ideas of where to get a cat and y-pipe that will pass inspection and have same or better peroformance.

I found one link for a cat but it has no flanges:

cat convertor link

Any other places to get good stuff for my LS400 would be greatly appreciated......

lorenzo816

$4821.70 from the "stealer" and done with $790.00 from local shop

Guys, it never ceases to amaze me.

I know everything that I could have got from the Lexus dealer would have fit perfectly.
But that is WAY too much money when Cats cost 90 - 300 dollars for good ones.

So my local shop did a crazy welding job and put the smallest Cat-co Cats they had in stock (if I ordered them smaller it would have been longer wait - need car now!) and used the old y-pipe to fit everything as nice as they could.

Sounds throatier - if that is a word - and I also had a BG induction/injection system job done on it. I recommend it for anyone with a high mileage car.
You should have seen the crap coming out of the tail pipe!

Car runs smooth, but I've got two codes "21 and 31" Main O2 sensor signal/heater signal and the Air flow meter signal.
For more on codes from an OBDI go to:
troublecodes.net/lexus/
I'll fix that crap tomorrow.

I'll post pics of the weld job that they did If anyone wants to see.

And guys it is still mean as **** to floor the Lex on the highway!!!!!!!

Yeeee-Haaaaa!


Oh and I hate talking to myself so I hope this comes in Handy for anyone who has issues with their 1rst Gen Lex.

lorenzo816

Hope I don't **** anyone off with the non-japanese cats.
But I saved a lot of loot and still have a 50k warranty.

Here is a pic of the new exhaust and I have highlighted some things I'm not too happy with but I'll live with.
First the O2 sensors are hanging exactly opposite as OEM and risk being scraped which is why I taped them up with gaffe-tape to protect the wires.
And I didn't quite like the hangers on the exhaust but they are welded to the exhaust pipe and bolted to the car - SO it Does come Off if needed.
They still used the old Y-pipe but cut off the cat - of course - and welded some new sections to the pipe so the angle would line-up just right.
The cats are a little bigger, couldn't wait for smaller ones.





and here is a diagram from walker.
The circled y-pipe with convertor is a straight bolt-on piece but it is 1850 dollars, and the cats are 900 a piece - heck no!





Sounds still quiet outside the car.
Sounds throaty in the car and now that it can breathe, Man! does it fly.


thoughts, and criticism is accepted.

Hope this helps everyone.

LS400 1992 170k

Lorenzo