archer973
Well-Known Member
- Joined
- January 31, 2014
- Messages
- 112
- Reaction score
- 3
- City, State
- Mt. Vernon, WA
- Year, Model & Trim Level
- 1998 Ford Explorer XLT
History: Vehicle on road traveling about 45 MPH when several backfires occurred accompanied by fireballs from the exhaust. A compression test indicated a timing chain had slipped causing low compression in all right side cylinders. Towed home and placed in garage for 10 years. I acquired the vehicle and started an engine rebuild--ongoing spare time project chronicled in my thread 1998 Explorer XLT Resurrection. I recently reinstalled the engine which runs fine, but I observed the right side catalytic converter is glowing red hot.
An initial online search into this problem revealed the most common cause is unburned fuel in the engine exhaust or a plugged catalytic converter. A compression test of the engine indicated all the valves were closing, so I concluded the catalytic was plugged and ordered a new one. $170 dollars later, I still have a glowing catalytic converter. I spent a couple of hours yesterday reviewing other threads here and in other forums looking for a solution to the problem. Most of the threads contained many suggested solutions, but very few of the threads come to a conclusion, i.e., "I fixed it. This was the problem." So I am starting this thread focused on this problem alone and will follow through until I have a fix and posted the answer for others.
One suggestion I found is that the exhaust could be plugged further downstream from the catalytic, so I disconnected the muffler from the new catalytic. After starting the engine, it took longer, but eventually the catalytic started glowing again so I am back to thinking unburned fuel in the exhaust.
I am not ruling out I made a mistake somewhere in my rebuild that could cause this. Lots of hoses and wires unattached and reattached. New gaskets. Some new parts, some old ones, and some from a wrecking yard. My next step is to test the oxygen sensors and plug wires. Hoping I will receive some good tips from others here.
An initial online search into this problem revealed the most common cause is unburned fuel in the engine exhaust or a plugged catalytic converter. A compression test of the engine indicated all the valves were closing, so I concluded the catalytic was plugged and ordered a new one. $170 dollars later, I still have a glowing catalytic converter. I spent a couple of hours yesterday reviewing other threads here and in other forums looking for a solution to the problem. Most of the threads contained many suggested solutions, but very few of the threads come to a conclusion, i.e., "I fixed it. This was the problem." So I am starting this thread focused on this problem alone and will follow through until I have a fix and posted the answer for others.
One suggestion I found is that the exhaust could be plugged further downstream from the catalytic, so I disconnected the muffler from the new catalytic. After starting the engine, it took longer, but eventually the catalytic started glowing again so I am back to thinking unburned fuel in the exhaust.
I am not ruling out I made a mistake somewhere in my rebuild that could cause this. Lots of hoses and wires unattached and reattached. New gaskets. Some new parts, some old ones, and some from a wrecking yard. My next step is to test the oxygen sensors and plug wires. Hoping I will receive some good tips from others here.