[QLD] Catalytic Converter Problems [Lexus LS400]

[Zarconia]

Nah no vvt in this one, not until the 97' 1UZ-FE's

I'm also thinking that one of the cylinders isn't sparking and burning the fuel correctly. Going to go out get a timing light and confirm if it's the timing or not first

 

[ari666]

heat is usually caused by too lean. if its not sparking itll be too rich.

 

[delcowizzid]

it only takes a dead plug or coil or its just kissed a valve when the belts snapped and its not sealing fully to cause a missfire and the cats will start to glow .and these do in coils quiet often.
does it sound smooth and on all 8.
use the timing light to check for dead plugs/cylinders as well as ignition timing.if its retarded a fair bit it will glow the headers and cats quick smart.
failing that do a compression test and leakdown test to check valve condition.you could even fit a vacuam gauge to check valve seal

 

[Not_An_Abba_Fan]

Or if you want to test it without the cats hooked up, but it will be loud....

 

[Zarconia]

Yeah good points I'll smash in tomorrow with the compression tester and timing light and pray it's not the valves. It does sound very smooth and does sound like it's running right until you play with the throttle straight after it's started up. About 5 minutes of playing with the throttle it just gives loud popping or backfire through the intake but after that it stops then the cats start to glow but headers remain unaffected

 

[Zarconia]

Played with the timing light and found the first problem, one of the vacuum hoses have snapped and wont sit properly and plays with the timing something chronic. Going to see if i can fabricate something back on so it connects back in properly. Don't know what the hell the part is called so if this doesnt work I have no idea how to go about getting a new one or what to call it. It's like a part of the intake with vac lines attached almost like a huge plastic tube it doesn't even store any air in it. Not 100% but i'm thinking it has something to do with the EGR valve

 

[delcowizzid]

you might be able to drill it out and screw in a brass fitting.worst come to worst you could melt it closed with a soldering iron and fit a tee inline in the rubber hose

 

[ari666]

just get a piece of metal tube, heat it up on the stove or a lighter or something, melt it into the plastic then araldyte the edges to ensure its sealed.

edit*

you might be able to drill it out and screw in a brass fitting.worst come to worst you could melt it closed with a soldering iron and fit a tee inline in the rubber hose

or that

 

[Zarconia]

Great minds think alike! Got a brass fitting and melted it through the plastic to mold into place then slapped some cold weld around it now sitting to dry