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Help! Cat glows red!

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Old 05-23-12, 09:18 PM
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Help! Cat glows red!

so i bought a 85 SE with 77,000 miles. Ran good for one trip around the neighborhood then lost power. I just happened to look under and saw the cat was red so i figured a clogged cat. I took it off but still don't have any power and the cat looked ok. I don't know else could be causing it. ACV maybe? BAC? I have no idea.
Old 05-23-12, 09:54 PM
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before you went through the trouble of removing the converter, you should've felt the exhaust pressure emmitting from the muffler. strong pressure equals good main converter.

glowing cat can mean a rich mixture, incorrect timing or faulty air pump or air tube.

i would run a compression text next.
Old 05-23-12, 10:05 PM
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The previous owner had the same problem two years ago, driving it home and lost power so he parked it. I picked it up got a new battery and started right up and ran just like it was supposed to. Ran in place for 10 minutes straight. Trailered it home. I went out this afternoon and it ran just fine, drove fine for about 5 minutes now this. I had some good ignitors around so i changed them. The cap and button look new and spark plugs look and fire ok. Check and it has good compression, timing is correct.
Old 05-23-12, 10:31 PM
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Did you check the pre cats?

Originally Posted by Tsi_Xtreme
The previous owner had the same problem two years ago, driving it home and lost power so he parked it. I picked it up got a new battery and started right up and ran just like it was supposed to. Ran in place for 10 minutes straight. Trailered it home. I went out this afternoon and it ran just fine, drove fine for about 5 minutes now this. I had some good ignitors around so i changed them. The cap and button look new and spark plugs look and fire ok. Check and it has good compression, timing is correct.
Did you check the pre cats? There's three total.
Old 05-24-12, 02:57 AM
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there are actually two pre catylitic converters and one main converter. when the pre cats fail, they usually shoot their internals into the main converter causing it to clog or break apart.
Old 05-24-12, 03:47 AM
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Originally Posted by mazdaverx713b
there are actually two pre catylitic converters and one main converter. when the pre cats fail, they usually shoot their internals into the main converter causing it to clog or break apart.
i haven't check he pre cats but the main looked fine on the inside, not even black really so I think the pre is fine.
Old 05-24-12, 12:05 PM
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Originally Posted by Tsi_Xtreme
i haven't check he pre cats but the main looked fine on the inside, not even black really so I think the pre is fine.
checked the pre cats today, just as i thought they were fine. I tested the Air flow meterd, water coolant sensor, checked the fuel main relays. Running out of ideas! I'm going to check the fuel pressure next i guess and see if the fuel pressure regulator is not working. Only other thing i can think is that the fuel injectors are stuck open and dumping fuel but hell i have not idea. Starting to lean towards the ECC itself, maybe its messed up.
Old 05-24-12, 12:13 PM
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first check to see if you have leading spark, if you lost leading spark to the plugs then the engine will run severely retarded ignition timing, have a real lack of power and burn extremely hot in the exhaust.

excessively rich mixtures would also cause the hot cat but you wouldn't notice quite a severe lack of power from the car unless it was emitting black smoke and choking you out, smelling like a gas station.

if the above isn't a symptom then next see how well the car idles, if it idles smooth and accelerates somewhat decently then you may have a good engine. if it stumbles and sounds rough like a lawnmower with a paint shaker vibration then your next step will be to do a compression test. faulty apex seals will still pull fuel into the engine but cannot compress it to burn it, all that fuel is dumped into the exhaust and heats up the exhaust quite toasty.
Old 05-24-12, 01:14 PM
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Originally Posted by Karack
first check to see if you have leading spark, if you lost leading spark to the plugs then the engine will run severely retarded ignition timing, have a real lack of power and burn extremely hot in the exhaust.

excessively rich mixtures would also cause the hot cat but you wouldn't notice quite a severe lack of power from the car unless it was emitting black smoke and choking you out, smelling like a gas station.

if the above isn't a symptom then next see how well the car idles, if it idles smooth and accelerates somewhat decently then you may have a good engine. if it stumbles and sounds rough like a lawnmower with a paint shaker vibration then your next step will be to do a compression test. faulty apex seals will still pull fuel into the engine but cannot compress it to burn it, all that fuel is dumped into the exhaust and heats up the exhaust quite toasty.
i have both and thats whats so crazy. i have good compression and fire.
Old 05-24-12, 01:31 PM
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is your distributor clamp bolt loose? the distributor may have reclocked to a retarded position.

last alternative would be bad float seats in the carb, dumping fuel from the overflows into the carb throats causing a severely rich condition but if that was the case i doubt the engine would even idle.
Old 05-24-12, 02:00 PM
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Originally Posted by Karack
is your distributor clamp bolt loose? the distributor may have reclocked to a retarded position.

last alternative would be bad float seats in the carb, dumping fuel from the overflows into the carb throats causing a severely rich condition but if that was the case i doubt the engine would even idle.
timing is spot on. its Fuel injected its a GSL-SE
Old 05-24-12, 02:15 PM
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check your fuel pressure, could be a clogged return line increasing fuel pressure and causing a rich condition.
Old 05-24-12, 02:51 PM
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not going to believe this.... one freaking spark plug! All this testing and trouble over one freaking spark plug! But she runs!
Old 05-25-12, 06:25 PM
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was the metal around the grounding points corroded? had this happen once to me. replaced the plug and all was fine after that.
Old 05-25-12, 06:37 PM
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Glad it worked out in the end, LOL




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