It appears one or both of the cats are bad. P0420.

Has anyone found a reasonable solution to this?

Parts and labor will almost cost more then the car is worth.

I'm in Colorado so we do have to do emmissions testing here.

Thanks in advance.

 

Google o2 simulators, also if you move the sensors out of the exhaust stream with oil foulers for spark plugs(dorman sells) this many times is enough to make them "think" the cats are still working properly. Dont be tempted to use aftermarket cheaper cats. Youll waste your money. I have taken many off and had to argue with customers about the problem.
"its gotta be something else, i just replaced those last yr!"
no theyre cheap crap and that why when i sell used cats i get about $50-75 per car for a oem, and $5 for aftermarkets. They just dont have enough of the precious metals that the cats use to clean the exhaust. Which sucks because labor on the rear cat is expensive. Front is pretty easy

 

Brutal,

When you say aftermarket, does that include this one?



BENCHMARK CATALYTIC CONVERTER ASSEMBLY

Benchmark catalytic converters are considered to be the industry's standard replacement catalytic converter. It is the recognized leader in fitment and durability. It features perfect fit and repeatability and its performance results are continually monitored by Benchmark's internal emissions laboratory to insure quality loadings which eliminate OBDII issues caused by many universal catalysts.

Specifications

• With oxygen sensor port
• Standard assembly with one catalytic converter

Notes

• 49-state legal; Not for sale or use in California; Cannot be shipped to California addresses

• Location: Front
• Color/Finish: Natural
• Emissions: 49-state legal - no CA shipments
• Product Fit: OE replacement
• Quantity Sold: Sold individually

• Tube Material: Steel
• Case Material: Steel
• Anticipated Ship Out Time: 1-3 business days
• Catalytic Converter Quantity: One
• Warranty: 2-year or 25, 000-mile Benchmark limited warranty

Fits the following 2003 Jaguar X-Type</STRONG> submodels:

• 2003: Base; 6 Cyl 2.5L;

 

Yep although they at least stand behind it for 2yrs instead of 1. Theres a reason why its not legal in cali(does clean enough) and the orginals last much longer which is covered by a 8/80 from new. That says front so im assuming you need to replace the easy 1. Had misfires in the past, lean engine codes? Those are many issues that take out cats. Make sure the original issue is fixed before you throw cats at it

 

Brutal,

The p0420 codes was the first code to come up. We ignored it because it passed emmissions so easy and the code would come and go.

Then some time much later the car started studdering but still runs after the RPMs are up.

Do you still thing that if I replace the cat I will have other issues?

If so I am not sure the car is worth repairing.

 

Is that still the only code? You may have other like lean engine or msifires. Ide check. You can get away with not replaceing cats for awhile if. You can clear the code, drive the car and the monitors reset without reseting a check engine light when the cat monitor recheck and resets. Its when you clear and it returns rightaway that youll have to replace it.

 

i have a pair of v6 decat pipes with o2 sensors in them. good condition, will need to use your own headers. if there any use to you. im in the uk and can post if wanted. 90gbp plus postage

 

There are other codes as well. I don't have them in front of me but it like misfire #5 and some others.

If we clear the codes they return fairly soon.

I drove it this weekend and it stutters at first when backing out of the garage, but then doesn't run bad at all.

 

Jimbobsgts,

Tempting idea.

How much is 90gbp in US $?

 

>How much is 90gbp in US $?

$140 plus shipping...
================================================
Jaguar: Grace, Pace, and Space - Sir William Lyons

 

Does anyone have any input on an "O2 sensor spacer"? I've seen them online but do they really work?

 

I would think the decat pipe would make your car fail its emission test!!