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Catalytic Converter Overheating

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Old Apr 28, 2025 | 03:10 PM
  #31  
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OK put all the relays back into their positions ,
take the the horn relay and put it into the starter relay position see if it will crank
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Old Apr 29, 2025 | 03:33 PM
  #32  
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From: INDY
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Well I was skeptical that would work because I knew the other relay had functioned on the horn. It’s cranking now and has fuel pressure. I was able to press the gas pedal down and get it started. I can at least get it to start for a baseline of my troubles. This is absolutely amazing and crazy. Mind blown

I do appreciate the guidance and now to the matrix chart. (Miss fires)

I also plan to check the continuity of the three wires to the CPS because my sensor works fine and is probably five years old and not many miles on it.
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Old Apr 30, 2025 | 10:05 AM
  #33  
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Originally Posted by Want to be

Cats, yeah I realize I might need to replace them and I’m not excited about it. I’ve removed the exhaust more than once but that’s a ways down the road.

Thanks
…and maybe not unless the matrices are broken. That inexpensive Harbor Freight boroscope can help tell the story there. With the cars pulled off the pipes, the boroscope can see into both ends as to if the matrix is intact or not.
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Old Apr 30, 2025 | 10:31 AM
  #34  
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OK so you had a bad starter realy.
NOTE they go bad due to a few things, the first is many starts with a low state of voltage battery.
This prevents the contacts from making a solid contact and over a period of time,
the contacts get dirty and carbon up you can usually clean these contacts.
However its easier to replace the relay.
The other thing is extended starting cycles due to a non running engine,
and some times accompanied by a battery booster ,
this spike can fry the coil wire in the relay.
Bottom line keep the battery charged and disconnected if the car is going to sit for more than a week.
This will preserve the battery charge for when you need it.
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Old May 2, 2025 | 07:56 PM
  #35  
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From: INDY
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Thanks for the information on battery tending.

Well, I have figured out the ignition issue, and I am very embarrassed to say what I did, but I am sure there will be another idiot (like myself) who might make the same boneheaded mistake.

After some thought about the ignition system, I then began to wonder if the rotors were placed in the correct position. So, I took off the distributors and each timing cover. I rotated the engine to TDC, and guess what I found. The rotors were not placed in the correct position. I'm like... that would cause a problem.

So, I put the rotors in the correct position, and guess what happened? The car started on the FIRST crank—almost instantly.

It ran pretty good for several minutes, but later began to haunting on the idle. I need to get everything tightened up and put the airbox on the car to see if the car just needs a good run since it hasn't been on the road for 6 plus months.

I do appreciate everyone's help, and I apologize if I wasted everyone's time. I am very embarrassed by this one.... Oh well... that won't happen again.

Last edited by Want to be; May 2, 2025 at 07:57 PM.
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Old May 2, 2025 | 09:27 PM
  #36  
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Originally Posted by Want to be
Thanks for the information on battery tending.

Well, I have figured out the ignition issue, and I am very embarrassed to say what I did, but I am sure there will be another idiot (like myself) who might make the same boneheaded mistake.

After some thought about the ignition system, I then began to wonder if the rotors were placed in the correct position. So, I took off the distributors and each timing cover. I rotated the engine to TDC, and guess what I found. The rotors were not placed in the correct position. I'm like... that would cause a problem.

So, I put the rotors in the correct position, and guess what happened? The car started on the FIRST crank—almost instantly.

It ran pretty good for several minutes, but later began to haunting on the idle. I need to get everything tightened up and put the airbox on the car to see if the car just needs a good run since it hasn't been on the road for 6 plus months.

I do appreciate everyone's help, and I apologize if I wasted everyone's time. I am very embarrassed by this one.... Oh well... that won't happen again.
You are not the only one. I recently finished a timing belt job on my 16V with lots of other items including replacing the distributor seal. I was certain I stabbed the distributor back correctly. After several rough starts, I left it until the next day when rested. I had the rotor pointed at cylinder 8 instead of cylinder 1 despite double checking. Once the rotor was corrected, it fired right up.
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Old May 2, 2025 | 11:13 PM
  #37  
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well thats great you figured it out.
I will go back to my favorite question.
What was the last thing you fixed?

NOTE the stumbling idle is normal if you had the air cleaner off,
this will let different amounts of heated air fill the engine bay as the engine runs for more than a few mins,
and the result will be the MAF trying adjust the mixture and then ICV trying to maintain a smooth idle.
Install the aircleaner housing and the intake tubes then see how it runs.
NOTE with all of starting you have done its also possible the plugs could be fouled.
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