1993 Cadillac Deville catalytic converter

Tiny
IMWHOYOUARENT
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  • 1993 CADILLAC DEVILLE
Smells problem
1993 Cadillac Deville V8 Automatic 200k miles

when I first bought this car coming out of the country something went up under the car and hit my catalytic converter few minutes later on thi highway something fell off a dump truck and hit the converter again there are two diff dents on the thing itself. Since then my converter has been making a loud rattling noise sometimes it wouldnt more often than not it does (im assuming its something loose in there). One night I was driving my car it overheated cause of a slow leak from the radiator at the top bolt with the hose on the other side of the cap. Ever since it overheated the converter has been ore loud, the car feels like a vibrating bed in a cheap motel and you can smell gas while its running only. What do I need to do to make my car run better again?
Thursday, January 29th, 2009 AT 1:42 PM

9 Replies

Tiny
JACOBANDNICKOLAS
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Hi:
It sounds like the catylatic converter needs replaced. It sounds like it melted down inside and not allowing pressure to release. Check at the exhaust to see if there is pressure. Let me know what you find.

Joe
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Sunday, February 1st, 2009 AT 9:23 PM
Tiny
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Exhaust from tail pipe is goin put put put very lightly while car is on and idling. Too bad this isnt a o it yourself type fix on my car the cat has been welded into the pipes rather than bolted up : /

if I cut my cat out there oughta be a way to put a new one up without welding rite?
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Sunday, February 1st, 2009 AT 10:07 PM
Tiny
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Hi:
Check with the local parts store. They may have a universal converter that will allow you to cut the old one out and clamp the new one in.

Let me know what you find.

Joe
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Monday, February 2nd, 2009 AT 5:37 AM
Tiny
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Sry for taking so long to get back to yall just barely got the new cat, muffler, thermostat, repaired and cleaned raditor, oil change, and tune up done to it.

But. I have to give it some gas when I turn it on from letting it sit a few hours in order to catch and stay running. It also idles rough especially in drive :(

i was thinking egr valve but want to be sure cause that is an expensive part.
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Sunday, March 29th, 2009 AT 7:48 PM
Tiny
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Is the car running better than it did? Also, a rough idle can be caused by a few things. It could be the EGR, a vacuum leak, in need of a tune up. Have any of those items bee checked? Also, the temp sensor could cause a rough start.

Let me know.
Joe
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Monday, March 30th, 2009 AT 1:53 PM
Tiny
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I havent checked the egr valve yet not too sure on how to tell if its bad. Ive checked all the lines I could without tearing the motor apart and they dont look bad just old. I did a tune up the rotor was melted roun the metal changed the dist. Cables and the front row of plugs. Plugs still look pretty good little darkened but still sparks and did an oil change. I also unplugged the cables from my dist. And cranked the car to listen for any inconsitencies all is well with that. I put in a new thermostat if that is the thing you were talkin about for temp.
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Tuesday, March 31st, 2009 AT 8:36 AM
Tiny
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The temp sensor is a sensor that tells the computer how cold or hot the engine is so it knows how rich to make the fuel. It takes the place of the old choke on a carb.

As far as the EGR, it is a valve. You need to make sure it doesn't have any carbon build up that would block vacuum and make sure when the valve closes, it seals (no dirt or carbon is blocking it.

As far as the vacuum lines, they may be fine, but when they get old and hard, they can leak. Some mechanics spray starting fluid on them with the car running to see if it chances the idle. If it raises, there is a leak. The problem is, this is a very dangerous process because it the starting fluid / carb cleaner hits an exhaust manifold or other component that is extreamly hot, you can have an instant fire. The process will find a leak, but you must be careful
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Tuesday, March 31st, 2009 AT 9:40 PM
Tiny
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I found a couple old tubes with cracks in them replaced them and no more suckin noise :)

as for the egr valve im thinkin its shot. I replaced the tube on that and with the car running I puled the tube off of it and the car did not change in any way, no idle up and no idle down, was as if the egr valve had nothing to do with the car lol. Unfortunately this is an expensive part for me at the moment while I look for another job (lay-offs suck). If I were to continue driving this car like this wat is the likelyhood of my car becomming badle damamged? After the car is started it runs fine. The rough idling at a stand-still has subsided some with new tubing but not completely gone.
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Wednesday, April 1st, 2009 AT 5:54 PM
Tiny
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A rough idle shouldn't hurt anything. And I agree, layoffs do suck. Chances are the EGR sounds bad.
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Wednesday, April 1st, 2009 AT 9:26 PM

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