Catalytic converter replacement?

Tiny
ANONYMOUS
  • MEMBER
  • 2003 FORD FOCUS
  • 209,000 MILES
My car has a noise, especially when I have it on but with the brakes on, is a noise that sounds as if all the pieces to move, and the sound is only when the vehicle brakes or do I have on but with the brakes on. What can that be, Will by the catalytic, as is the light on and the only code that gives is catalytic. But the damaged catalytic makes so much noise. The catalyst is very expensive and I do not want to change it until you are sure that this is due to the catalytic. I can not spend all that money so that the noise remains the same, and I want to be sure that noise is the problem of catalytic, or other think.-
Saturday, November 10th, 2012 AT 8:02 AM

21 Replies

Tiny
ASEMASTER6371
  • MECHANIC
  • 52,796 POSTS
The code for the cat means the cat is done and worn out. no matter what else, the cat is no good.

This guide will help walk you through the replacement.

https://www.2carpros.com/articles/catalytic-converter-replacement

Roy
Was this
answer
helpful?
Yes
No
Sunday, November 11th, 2012 AT 4:43 AM
Tiny
SMEKAF
  • MEMBER
  • 5 POSTS
  • 2002 FORD FOCUS
  • 4.0L
  • 4 CYL
  • 4WD
  • AUTOMATIC
  • 167,000 MILES
I changed the catalytic converter and spark plugs and it still gets red hot. Help!
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,796 POSTS
Good evening,

The catalytic turns red from unburned fuel in the system from the engine not burning the fuel correctly.

Does the engine misfire?

https://www.2carpros.com/articles/engine-misfires-or-runs-rough

Is the check engine light on? If it is, do you know the codes?

I would do a compression test to be sure the engine is good internally.

https://www.2carpros.com/articles/how-to-test-engine-compression

Roy

1. Open the central junction box (CJB) and remove the fuel pump relay.
2. Start the engine: the engine will start up, run for a few seconds and then stall.

imageOpen In New TabZoom/Print

NOTE: Turn the spark plug connectors slightly before pulling them off. Pull on the connector, not on the cable.

imageOpen In New TabZoom/Print

3. Pull off the spark plug connectors.
4. Pull off the ignition coil connector.

imageOpen In New TabZoom/Print

5. Remove the spark plugs and keep track of spark plug location for installation.
Images (Click to make bigger)
Thumb
Thumb
Thumb
Was this
answer
helpful?
Yes
No
+1
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
SMEKAF
  • MEMBER
  • 5 POSTS
So the sensors on the catalytic converter wouldn’t be the cause?
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,796 POSTS
No, they will not. This is an engine issue not burning all the fuel in the cylinders.

Roy
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
SMEKAF
  • MEMBER
  • 5 POSTS
Okay, so is it an easy fix?
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,796 POSTS
Diagnostics need to be done to find out why.

I asked about the check engine light.

I asked you to do a compression test.

That's is where you need to start. Once we determine the failure, then we can discuss the repairs.

Roy
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
YOGITECH1
  • MEMBER
  • 13 POSTS
  • 2000 FORD FOCUS
  • 4 CYL
  • FWD
  • MANUAL
  • 136,000 MILES
I have replaced the plugs, wires and coil. I have an engine light P0420 catalyst below threshold, was cleared and stayed gone for two days. Power is good when I take off but when holding the throttle steady it has an occasional surge like it is missing but no strong bucking. What else could be causing this issue? I have looked at the O2 readings and they seem to be W/I perimeters so don't know what is triggering the code either.
Michael
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
BLACKOP555
  • MECHANIC
  • 10,371 POSTS
Were the plugs and wires replaced for a reason?

that code means that the post converter o2 sensor is malfunctioning, or the catalytic converter has failed. which would make sense if you replaced the spark plugs and wires due to a problem that could have been pumping out raw fuel and burning up the converter!

This guide will help confirm the issue

https://www.2carpros.com/articles/how-to-test-a-catalytic-converter

also if the front o2 sensor(s) fail or misread it could cause the back one to throw a code as it is used as a reference for the catalyst efficiency.
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
SMEKAF
  • MEMBER
  • 5 POSTS
I can’t drive it to AutoZone because it gets red hot too fast and it starts smoking.
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
YOGITECH1
  • MEMBER
  • 13 POSTS
I replaced the plugs as I believe they were original and the wires were leaking voltage, they had burn marks, I looked at the information last night again and although I couldn't get the info for the downstream O2 the upstream seemed to be all over the map form 70V to just under 800V with in m/sec. I believe this may be the problem as this appears to be erratic. Do you believe this would cause the fuel mixture to vary enough to cause the surging?
Just a little info on me I'm retired from the automotive field this issue just confused me.
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,796 POSTS
AutoZone is not where you belong. They sell parts and do not do repairs.

You need a shop to check this for you if you cannot do these checks. If this is your only wheels, then maybe you could get a tech to come to you and check it out.

Roy
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
BLACKOP555
  • MECHANIC
  • 10,371 POSTS
If it's varying that much it could cause that problem, especially if it's with it causing a lot of fuel to be pumped in then hardly any at all.

What I would do is disconnect the o2 sensor and run it, if the problem goes away then suspect the o2 sensor or harness for the o2 sensor.

Does it run good when cold? In closed loop.
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
SMEKAF
  • MEMBER
  • 5 POSTS
I was going to AutoZone for the diagnostic test, but okay thanks.
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
YOGITECH1
  • MEMBER
  • 13 POSTS
Yes, it runs this way when cold also, and I'll try running it without the o2 plugged in.
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
ASEMASTER6371
  • MECHANIC
  • 52,796 POSTS
Okay,

You are welcome.

Keep me updated.

Roy
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
BLACKOP555
  • MECHANIC
  • 10,371 POSTS
If it does not work with o2 sensor unhooked. Leave the sensor unhooked and remove the battery for about 10 minutes, reconnect battery and start, does it run?

Let me know what you find.
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
CHRISBLOOM
  • MEMBER
  • 1 POST
I have a 2000 Focus, did the whole surge and hesitate thing. Replaced fuel pump motor filter, coil pack, all the sensors nothing worked. Acting like it had no fuel but when tested it was right with in specks. So we got mad and cut thru the floor and accessed the fuel pump that way, yeah kinda drastic but we had a hunch. Opened up the tank and took a spin. Here the pump was spraying gas all over the place. The o-ring at the top of the motor into the assembly had failed and the little white one-way pressure valve that the pump pumps through first then out of the tank, that was clogged. So we replaced the entire unit this time instead of just the pump motor. Fixed it.
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
DANNY L
  • MECHANIC
  • 5,648 POSTS
Hello, I'm Danny.

Thanks for the input. Thanks for using 2CarPros.
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)
Tiny
RW7
  • MEMBER
  • 1 POST
  • 2000 FORD FOCUS
  • 4 CYL
  • FWD
  • MANUAL
  • 130,000 MILES
Ok I have a 2000 ford focus zx3 and I started notessing a few days ago after I would go above 4000 rpm it didnt really have any power. Then today I started my car and I let it warm up and I drove it about 2 or 3 miles and I was on the hi-way and once I got up to 70 it was like it wouldn go any faster, I had the petal to the floor and it didnt go faster and didnt slow down. So I got off the hi-way and it started sputtering, and almost dying first thing I thought of was maybe the gas was bad but it was new gas it hadnt been sitting in the car or anything so I thought it might be the fuel filter, and so I changed the fuel filter and there was some junk in the old one it was kinda brown but wasnt really gritty at all, so like before I started my car and let it warm up and after about 3 miles it did the same thing over again, sputterin kinda dying out, didnt make any grinding or wierd sounds just sounded normal. Could it be the catalytic converter? I have no idea. Thanks
Was this
answer
helpful?
Yes
No
Tuesday, July 28th, 2020 AT 6:18 PM (Merged)

Please login or register to post a reply.

Related Catalytic Converter Replace/Remove Content

Catalytic Converter Replacement
GUIDE
Catalytic Converter Replacement
The cat­alytic con­verter is a crit­i­cal com­po­nent of your ve­hi­cle's ex­haust sys­tem, re­spon­si­ble for re­duc­ing harm­ful emis­sions by con­vert­ing toxic gases into less harm­ful...
VIEW MORE