Do Not Sell My Personal Information Jump to content

1991 Ls400 Overheating Catalytic Converter


akibe
 Share

Recommended Posts

I have a 1991 LS400 with 260000 miles.i changed timming belt and water pump 8 months ago.About 2 months ago i had a problem with radiator and i never used it for those two months (never overheated).After replacing radiator and trying to reuse it after 2 months not being used,it now overheat(red hot) catalytic converter.Does anyone have an idea where the problem could be.I replaced all eight plugs and did not solve the problem.The engine also has no power as it used to be before going to rest.Please help

Link to comment
Share on other sites

Did you do the the timing belt & water pump change yourself....Are you sure the timing is correct.... Incomplete fuel conbustion dumping into the exhaust & into the cats will cause them to get red hot.....Very dangerous......

Be careful.....check your timing.....as to your overheating....are you sure you have the correct tension on your timing belt.....may not be enough tension on the water pump to create good circulation....thus overheating on you.....check your thermostat as well.....

Possible that radiator is clogged up somewhere....

Good luck.....

Link to comment
Share on other sites

I have a 1991 LS400 with 260000 miles.i changed timming belt and water pump 8 months ago.About 2 months ago i had a problem with radiator and i never used it for those two months (never overheated).After replacing radiator and trying to reuse it after 2 months not being used,it now overheat(red hot) catalytic converter.Does anyone have an idea where the problem could be.I replaced all eight plugs and did not solve the problem.The engine also has no power as it used to be before going to rest.Please help

The honeycomb structure holding the catalyst inside the converter has crumbled apart and portions are blocking the exhaust flow.

Link to comment
Share on other sites

This is kinda off-topic, but worth mentioning. I have read several cases of "glowing red" cat converters and now here is another, but it only seems to be issues on the 1991 models. I have NEVER heard anyone with a 90, 92 or newer complain of this problem- only the 1991s. Has anyone else noticed this, or have heard of this problem on 1990, 1992-94's as well? I am wondering if there was not just a problem with the converters they used in 1991. :unsure: One would assume they would be identical, but it seems to be a trend on the 1991s... at least what is mentioned on the Lexus forums.

Link to comment
Share on other sites

This is kinda off-topic, but worth mentioning. I have read several cases of "glowing red" cat converters and now here is another, but it only seems to be issues on the 1991 models. I have NEVER heard anyone with a 90, 92 or newer complain of this problem- only the 1991s. Has anyone else noticed this, or have heard of this problem on 1990, 1992-94's as well? I am wondering if there was not just a problem with the converters they used in 1991. :unsure: One would assume they would be identical, but it seems to be a trend on the 1991s... at least what is mentioned on the Lexus forums.

Well, I stand corrected. I just did a search and seen complaints of a 1992 and 1994 doing this as well, but it mostly seems to be a 1991 issue, at least mentioned here.

Link to comment
Share on other sites


Did you do the the timing belt & water pump change yourself....Are you sure the timing is correct.... Incomplete fuel conbustion dumping into the exhaust & into the cats will cause them to get red hot.....Very dangerous......

Be careful.....check your timing.....as to your overheating....are you sure you have the correct tension on your timing belt.....may not be enough tension on the water pump to create good circulation....thus overheating on you.....check your thermostat as well.....

Possible that radiator is clogged up somewhere....

Good luck.....

Timming belt,water pump,thermostat were changed by a qualified mechanic.And i used the car 8 months without problems.problem came after sitting for 2 months without driving it.Radiator is new,and i replaced it myself.Today am cleaning thorett body to see what will happen.Thanks

Link to comment
Share on other sites

Sounds like the famous loose wire to the left side (looking at the engine from the drivers side) lower coil. Causes the loss of half power, and red hot cats. Seems the left side wire to the coil can be affected by gravity if it gets loose-usually a defective cap on the coil wire. You might have hit it while doing all the other work. Hope this is the problem-cheap fix....

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

×
×
  • Create New...

Forums


News


Membership