Drivers side Cat went bad...


GT35065

GT Owner
Mark II Lifetime
My engine light came on and I brought my car in to have it checked. Used the same tech who changed my axle bolts, and he seems good. He was able to tell with his laptop plugged in that the #2 bank cat is not functioning. Car has 1500 miles on it. The price on one cat from Ford is $1500, so I'm glad its a warranty item.
Can anyone give me any tricks I can pass on to Russel for R&R of the drivers side (#2 bank) cat? He hasn't had to do one yet and the service manual makes it look like a ton of steps. He is having it shipped overnight, so any help would be appreciated.
He has a drive on hoist we can use with some 2x6's for getting on the hoist. Think I'll call Jason and order a Heffner muffler. Looks like a perfect time for a swap.

Thank you for any help.

Rick
 

ViperJoe

GT Owner
Mark II Lifetime
Aug 17, 2006
1,305
Washington Crossing, PA
I seriously doubt the cat is at fault. O2 sensors or associated controls/circuitry would be more likely to cause the problem.
 

jamie

GT Owner
Mark II Lifetime
Sep 23, 2005
271
Virginia
I seriously doubt the cat is at fault. O2 sensors or associated controls/circuitry would be more likely to cause the problem.

I agree! I would get a second opinion or have him run a few different tests before they start tearing my car apart.
 

SFLGT

Well-known member
Dec 29, 2007
205
FtLauderdale,Florida
I have to agree also. It is not imposable I have seen cat problems with low miles before. If you feel confident in your tech and he feels that it is really a cat problem then it may be, but be sure that he has done a complete diag. Do you know what codes he found or any mode 6 data he may have checked? I don't know how involved with it you got. If the exhaust is going to come apart then yes you might as well do the cat back now if you planed on doing it.
 
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GT35065

GT Owner
Mark II Lifetime
Russel seemed very thorough in his tests and explained them to me. He was unplugging the sensors and running various tests. What he said and what the computer was showing made sense, however I don't have the knowledge to second guess him. It seems unlikely that the cat could go out with this mileage to me. My warranty is up in August, so I would rather have the cat put on then find out it is bad after warranty is up.

I still would like to know if there is an easier way for him to pull the cat than what the service manual is calling for. If any one can give us some advice, I would appreciate it.

Left a message for Jason at Heffner's about buying an exhaust, he didn't get back to me yet. I'm sure I will talk to him tomorrow.

Rick
 

Fubar

Totally ****** Up
Mark II Lifetime
Le Mans 2010 Supporter
Aug 2, 2006
3,979
Dallas, TX
I just pulled mine out (went with the cat delete kit from Ford Racing). It was not that complicated. Shadowman posted some great instructions in that thread.

You will not be removing the manifold so disregard the last portion of the instructions.
 

nota4re

GT Owner
Mark IV Lifetime
Le Mans 2010 Supporter
Feb 15, 2006
4,339
I agree with others here - it is very unlikely that it is your cat. I'd swap the rear-most O2 sensors from side to side and drive the car to see what happens. These rear O2's are VERY easy to get to and should take no more than 30 minutes to swap them. BTW, they are identical, with identical wire lengths, etc. If the symptom changes sides, you know it is the O2.

Not real cool to sock it to Ford unless you're sure, IMO.

Just so you know, there's really no risk to your engine or tune with this experimentation of the REAR sensors. Part of the Fed mandated OBDII standard (1996+) is that the OEMs must have the ability to detect cat efficiency and throw a trouble code when/if it occurs. The computer relies on the Front O2's for stoichiometric feedback.
 

GT35065

GT Owner
Mark II Lifetime
Fubar, thanks for the link, that should help.

nota4re, I respect the opionions very much on this board. I am calling Russell this morning and will have him check this thread. He is knowledgeable on these cars and has worked on a lot of them. I can assure you I have no desire at all to "stick it" to Ford. I also have no desire to pay some $1700 with labor to buy a faulty cat, if it is bad. This is the second time the engine light has come on, and it took three months for it to come back after being reset (200 miles). I know with the testing Russell did, he was certain the cat itself is bad. I'm not in a position to second guess him. I'll report back later and see what he thinks.

Thanks,
Rick
 
Aug 25, 2006
4,436
My engine light came on and I brought my car in to have it checked. Used the same tech who changed my axle bolts, and he seems good. He was able to tell with his laptop plugged in that the #2 bank cat is not functioning. Car has 1500 miles on it. The price on one cat from Ford is $1500, so I'm glad its a warranty item.
Can anyone give me any tricks I can pass on to Russel for R&R of the drivers side (#2 bank) cat? He hasn't had to do one yet and the service manual makes it look like a ton of steps. He is having it shipped overnight, so any help would be appreciated.
He has a drive on hoist we can use with some 2x6's for getting on the hoist. Think I'll call Jason and order a Heffner muffler. Looks like a perfect time for a swap.

Thank you for any help.

Rick


Very unlikely that it is a bad cat

Shadowman
 

BlackICE

GT Owner
Nov 2, 2005
1,416
SF Bay Area in California
I agree with others here - it is very unlikely that it is your cat. I'd swap the rear-most O2 sensors from side to side and drive the car to see what happens. These rear O2's are VERY easy to get to and should take no more than 30 minutes to swap them. BTW, they are identical, with identical wire lengths, etc. If the symptom changes sides, you know it is the O2.

Good advice! I have heard only 2 GT that have cat failures. But these cars with aftermarket tunes that were driven very aggressively for extended amounts of time. Most aftermarkets tunes turn off COT (Cat over temp) protection as well has flange temp protection. Ford designs the cats to last 100K miles and to minimize failures, the stock tune richens up the mixture to lower exhaust gas temps if the ECU thinks they may be getting to hot.

Swap the rear (post cat) O2 sensors and log pre and post cat O2 readings from both banks. That will tell you whats up. Maybe this is what your tech as already done.
 

SFLGT

Well-known member
Dec 29, 2007
205
FtLauderdale,Florida
Just by watching the voltages on the O2s and cat monitor pids and some freeze frame data should be enough for your tech to diag your problem. If you are confident in the tech working on the car and he is sure that you have a cat problem it is possible, but still unlikely. The only other thing I could suggest is to ask the tech to call hot-line before he orders the cat and give them his data and let them confirm what he thinks just to be safe. As far as your warranty running out and then finding a bad cat. Remember cats are warrantied for 8 years 80,000 miles.
 

GT35065

GT Owner
Mark II Lifetime
SFLGT

I just talked to Russell and that is exactly what he did. He said there is not a doubt in his mind that the cat is bad. He showed me on the lap top and explained it at the time, but I'm not a tech guy so I couldn't remember all that he said. He said they occasionally get new cars right off the truck with a bad cat, so it can happen.

I forgot about the extra warranty on pollution control stuff. I thought it was 5 year, 100,000 miles? In any case it is not the emergency I thought it was.

Ordered my Heffner exhaust from Jason yesterday. None in stock, but he will have it to me a week from this Monday. So cat job is waiting until then.

Appreciate everyones comments.

Rick
 

SFLGT

Well-known member
Dec 29, 2007
205
FtLauderdale,Florida
GREAT! Glad it is getting worked out for you. It's rare but it does happen. Sounds like you have a good thorough tech. You will love the Heffner exhaust.
 

Sinovac

GT Owner
Mark II Lifetime
Jul 18, 2006
5,864
Largo, Florida
Rick,

You need to put a Heffner pulley and tune in that car because those solid red GTs are s-l-o-w.
 

GT35065

GT Owner
Mark II Lifetime
Sinovac,
Bite me, you dark blue dust magnet:biggrin. Here is a picture of you trying to keep up with old red::eek:ld:

Loved your pictures from Grand Prix, especially of your son having a blast. Looks like you two had a great time. Any time he wants to see and or ride in the GT350, let me know. Maybe I can provide entertainment for the nice Largo police lady again...doh!

Rick
 

Beach-GT

GT Owner
Mark II Lifetime
May 8, 2006
887
Seminole Florida
It's the White Stripe that makes them go FAST.:biggrin
 

mousecatcher

GT Owner
Jun 26, 2007
200
San Mateo, CA
Good advice! I have heard only 2 GT that have cat failures. But these cars with aftermarket tunes that were driven very aggressively for extended amounts of time.

make that 3!

mine was passenger side, car was completely stock. blew a piece out into the muffler about 3 hours into a 4 hour track day :) . had to replace both cat and muffler (under warranty).
 

BlackICE

GT Owner
Nov 2, 2005
1,416
SF Bay Area in California
make that 3!

mine was passenger side, car was completely stock. blew a piece out into the muffler about 3 hours into a 4 hour track day :) . had to replace both cat and muffler (under warranty).

I was counting your GT already.