Great deals on TJ parts on Amazon!

Looking for parts for your Jeep Wrangler TJ? Checkout the selection of TJ parts Amazon has to offer, many with 2-day Prime shipping!

Click the image below to browse TJ parts on Amazon.

Jeep Wrangler TJ Parts on Amazon

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.

Glowing exhaust manifold on 2000 TJ 2.5

RAC02

TJ Enthusiast
Joined
Jul 27, 2019
Messages
176
Location
Jacksonville
Hello,
My 2000 Jeep Wrangler has been real load and I noticed today that the manifold is real red, basically overheating. The engine ideal has also been going up and down as well. The only code is a cylinder 4 misfire. I know their is a crack in the manifold however I never noticed how red it was. Any help would be much appreciated!! Thanks

06328D7B-1821-4229-B87C-55ECBCA7C187.jpeg




DE425A75-88B9-468A-9327-B5B8D94B8093.jpeg
 

SSTJ

Inexperienced Overthinker
Supporting Member
Lifetime Supporting Member
Joined
Aug 24, 2019
Messages
2,332
Location
South Carolina
I don't have advice to offer about what's going wrong, but if you decide to replace that manifold, I have notes from when I did it recently on my 97 2.5.
 
OP
R

RAC02

TJ Enthusiast
Joined
Jul 27, 2019
Messages
176
Location
Jacksonville
I don't have advice to offer about what's going wrong, but if you decide to replace that manifold, I have notes from when I did it recently on my 97 2.5.

Any thing would help. I just don’t know why it’s getting that red. If it is a clogged catalytic converter could I cut that off just to allow the hot air to escape? I wonder..
 

SSTJ

Inexperienced Overthinker
Supporting Member
Lifetime Supporting Member
Joined
Aug 24, 2019
Messages
2,332
Location
South Carolina
Any thing would help. I just don’t know why it’s getting that red. If it is a clogged catalytic converter could I cut that off just to allow the hot air to escape? I wonder..

I don’t know but I will be eager to hear what others say.

For tips on replacing the manifold, click on my build thread and then click on the ‘Maintenance’ link, where I put all my notes.
 

Daryl

2004 Rubicon
Supporting Member
Joined
Apr 29, 2018
Messages
2,829
Location
Earth 🌎
Raw fuel from the cylinder misfire is being burned in the catalytic converter. If you continue to run the engine like that you will ruin the CAT if you haven’t already. Fix the misfire and check the CAT for damage.
 

Squatch

Master Thread Derailer
Supporting Member
Joined
Oct 25, 2017
Messages
9,243
Location
Everett, Wash, United States
My 2000 Jeep Wrangler has been real load

Not entirely sure what you mean by this ^^^, but T from T and Daryl are setting you on the right path. I would start by dealing with the misfire first, and then perhaps be prepared to replace the cat, and even possibly the manifold. Cracking and/or warping are real possibilities with that much heat.
 
OP
R

RAC02

TJ Enthusiast
Joined
Jul 27, 2019
Messages
176
Location
Jacksonville
Ok I found one vacuum port on the bottom of the exhaust manifold that has no hose and from what I read should be capped. I changed my cylinder 4 spark plug and I will call the port tomorrow to see if that fixes it. O and I took the ideal control valve off and cleaned it. I’ll update!!!
 

SSTJ

Inexperienced Overthinker
Supporting Member
Lifetime Supporting Member
Joined
Aug 24, 2019
Messages
2,332
Location
South Carolina
Ok I found one vacuum port on the bottom of the exhaust manifold that has no hose and from what I read should be capped. I changed my cylinder 4 spark plug and I will call the port tomorrow to see if that fixes it. O and I took the ideal control valve off and cleaned it. I’ll update!!!

If your current manifold is not OEM, there are many aftermarket manifolds that have a port near the bottom, which was used for the YJ. They are known to come unplugged over time and cause issues.
 
OP
R

RAC02

TJ Enthusiast
Joined
Jul 27, 2019
Messages
176
Location
Jacksonville
I put the plug on the port. It did not change anything. I am wondering if there throttle position sensor needs to be looked at? Or maybe an O2 sensor could cause it to ring rich?
 

SSTJ

Inexperienced Overthinker
Supporting Member
Lifetime Supporting Member
Joined
Aug 24, 2019
Messages
2,332
Location
South Carolina
I put the plug on the port. It did not change anything. I am wondering if there throttle position sensor needs to be looked at? Or maybe an O2 sensor could cause it to ring rich?

Yea, I think that was Jerry's suggestion in that other thread that you just bumped for an update.
 
OP
R

RAC02

TJ Enthusiast
Joined
Jul 27, 2019
Messages
176
Location
Jacksonville
Have you made any progress on this?

Nope, changed the cylinder 4 spark plug, cleaned the spark plug wire. Cleaned the idle control valve, tps, and map sensor. Nothing yet has really changed anything. At first I cleaned the sensor with carb cleaner, then it drove worse, went back and cleaned with maf sensor cleaner and it’s a little better. I think the misfire is still there. I don’t have enough right now to replace every sensor so I’m guessing on which (if any could be causing the misfire). I have not replaced the 02 sensor yet. Maybe that is it. The code I get is bank 1 sensor 1.
 

SSTJ

Inexperienced Overthinker
Supporting Member
Lifetime Supporting Member
Joined
Aug 24, 2019
Messages
2,332
Location
South Carolina
Nope, changed the cylinder 4 spark plug, cleaned the spark plug wire. Cleaned the idle control valve, tps, and map sensor. Nothing yet has really changed anything. At first I cleaned the sensor with carb cleaner, then it drove worse, went back and cleaned with maf sensor cleaner and it’s a little better. I think the misfire is still there. I don’t have enough right now to replace every sensor so I’m guessing on which (if any could be causing the misfire). I have not replaced the 02 sensor yet. Maybe that is it. The code I get is bank 1 sensor 1.

I'm not sure, but I think that is the code for the upstream O2 sensor, right by the top of the down-pipe, where it meets the manifold.
 

Akitadog

Willy's Edition
Supporting Member
Joined
Jun 11, 2018
Messages
521
Location
The "209"
Can you check your timing?
Last time I saw red iron manifolds was when we would retard the timing to pass the old smog checks.
It would fire after the valve starts to open and burn the fuel when it was in the manifold.
 
  • Like
Reactions: Blondie70
OP
R

RAC02

TJ Enthusiast
Joined
Jul 27, 2019
Messages
176
Location
Jacksonville
Can you check your timing?
Last time I saw red iron manifolds was when we would retard the timing to pass the old smog checks.
It would fire after the valve starts to open and burn the fuel when it was in the manifold.

I don’t know how to do that. What tools would I need?
 

Fishtaco

TJ Expert
Joined
Sep 29, 2020
Messages
3,757
Location
Perth AU
Last time I had glowing headers was when my motor was cooking (not jeep) and a straight 6, the head gasket was put on upside down/wrong way around blocking the water jacket holes, how is your temperature? not all cooking motors blow steam some run red hot.