Jaguar XJS Catalytic Converters Comprehensive Guide

Jaguar XJS Catalytic Converters: The Jaguar XJS is a luxurious grand tourer produced by Jaguar from 1975 to 1996. It was available in various engine options, including 6-cylinder and V12 engines, but all models feature multiple catalytic converters in the exhaust system. These catalytic converters are crucial in reducing harmful emissions by converting pollutants into less harmful gases. The XJS’s advanced exhaust system with multiple catalytic converters ensures enhanced performance and compliance with environmental regulations.

Key Take Away

Direct-fit replacement Jaguar XJS Catalytic Converters are available from aftermarket brands like Autozone catalytic converter, Bosal, Eastern Catalytic, and Walker. Proper inlet/outlet dimensions and flange style must match the original converters. Jaguar XJS Catalytic Converters sold in California must be CARB-compliant.

Specific Details on the Jaguar XJS Catalytic Converters

Common Signs For Bad or Clogged Jaguar XJS Catalytic Converters

Check engine light: Warning light for the engine. Checking the engine warning light is a valuable way to tell whether or not there is a problem with the emissions system in your vehicle. A professional mechanic must check out your car immediately if the “check engine” light turns on in your dashboard.

Reduced fuel economy: Your car’s fuel consumption efficiency may suffer if Jaguar XJS Catalytic Converters malfunctions since it cannot convert dangerous exhaust gases into less harmful gases at the same efficiency level.
Engine Misfires: If Jaguar XJS Catalytic Converters aren’t working properly, it could cause engine misfires. This is because the catalytic converter cannot cut down on the quantity of carbon monoxide present in the exhaust fumes.
Increased Emissions: A catalytic converter in your car that isn’t working properly may cause increased emissions. This is due to the inability of the catalytic converter to transform hazardous exhaust gases into gases that are less detrimental to the environment.

Excessive Exhaust Noise: Noise from the exhaust system that is excessive. A catalytic converter that is not working fine can create noise from the exhaust system that is excessive. This is due to the catalytic converter’s inability to significantly reduce the quantity of noise produced by the exhaust gases.
Dark Exhaust Smoke: An exhaust with a dark color is a symptom of a clogged catalytic converter, which can also generate this exhaust color. This is due to the inability of the catalytic converter to transform hazardous exhaust gases into gases that are less detrimental to the environment.

Troubleshooting Tips for Jaguar XJS Catalytic Converters:

Check for P0420/P0430 codes pointing to converter failure using an OBD2 scanner.

Listen for rattling noises from the exhaust, indicating internal damage.
Inspect oxygen sensor performance upstream and downstream of converters.
Look for reduced performance, increased fuel usage, and rotten egg smells.

Use Catalytic Cleaner for catalytic converting cleaning

Installation Tips:

Always replace the exhaust inlet/outlet gaskets when installing the new Jaguar XJS Catalytic Converters. High-temperature silicone sealant can also be used to seal connections.
The inlet/outlet pipe diameter is 2.5″. Ensure the replacement converters have the proper 2.5″ inlet and outlet ports.

When secured to the manifolds, use a torque wrench to tighten the converter mounting nuts/bolts to the proper spec of 22-27 ft-lbs.
Carefully detach and reattach the oxygen sensors from the original converters to the new ones in their same locations.
Clear any check engine codes with a scan tool after installing the new Jaguar XJS Catalytic Converters. This will reset fuel trim parameters and monitor operation.

Tips for Cleaning Jaguar XJS Catalytic Converters:

Use a catalytic converter cleaner. Products like Catalytic Converter Cleaners can help break down and remove contaminants and deposits inside the catalytic converter. Follow the directions on the product.
Flush the catalytic converter. You can do this by adding the catalytic converter cleaner to your gas tank when filling up, and then driving the car for 30-60 minutes on the highway. The high speeds and engine heat will help circulate the cleaner through the catalytic converter to remove deposits.

Use a shop vac to vacuum out loose debris. Disconnect the oxygen sensor and carefully insert the vacuum hose into the catalytic converter inlet. Be careful not to damage the honeycomb structure inside.
You may need to remove the catalytic converter and soak it in a solvent-based or acid-based cleaner for heavy carbon deposits. Make sure to thoroughly rinse and dry it before reinstalling.
Avoid using engine degreasers or harsh chemicals that could damage the catalyst material inside the converter. Stick to products made explicitly for catalytic converter cleaning.

Be gentle in your cleaning methods to avoid damaging the converter. Over-cleaning or using too much pressure can harm the internal structure.
Consider having a professional mechanic do the cleaning if you’re uncomfortable with the process. They’ll have the proper tools and skills.

Some Tips For Properly Washing Jaguar XJS Catalytic Converters

Use a degreaser or catalytic converter cleaner. Spray it directly onto the exterior casing of the Catalytic Converters and let it soak for 5-10 minutes. This will help break down oil, grease, and carbon deposits. Avoid getting cleaner inside the converter.
Rinse the converter thoroughly with a garden hose or pressure washer. The high-pressure water will help blast away loosened contaminants.
Use a soft brush or rag to scrub the converter’s outside for stubborn deposits. Avoid abrasive pads or brushes that could damage the metal casing.

Ensure you thoroughly flush out any catalytic converter cleaner you use with plenty of water. Leftover chemical residue can damage the catalyst over time.
Dry the Jaguar XJS Catalytic Converters thoroughly after washing, using compressed air if available. Moisture left inside can also degrade the catalyst. Let the converter idle for 10-15 minutes to help evaporate any moisture.
Avoid using harsh chemicals like engine degreasers directly on the converter, as they can wash away the catalyst material and degrade performance over time.

Do not attempt to wash inside the converter or scrape at the honeycomb – this will destroy it. Only clean the outer casing.
Consider having a professional detail shop wash the catalytic converter if you don’t have the proper tools. They can properly clean it without damage.

The key is to be gentle and use only Catalytic Converter-approved cleaners. Thorough rinsing is important. Avoid excess moisture inside the converter.

Life Of Jaguar XJS Catalytic Converters

Under normal driving conditions, the OEM Jaguar XJS Catalytic Converters can average 120,000-150,000 miles.
The converters have an 8-year/80,000-mile federal emissions warranty. California emissions models have a 15-year/150,000-mile warranty.
Driving style has a significant impact. Many short trips and cold starts can foul the converters faster than more extended highway driving.

Poor engine maintenance, like oil leaks, bad spark plugs, or issues causing misfires, will degrade the converters quickly.
Contaminants like oil, coolant, or fuel getting into the exhaust can coat and damage the converter’s internals.
The upstream converter near the engine tends to fail sooner due to more heat cycling. The downstream one often lasts longer.

The efficiency declines if the Check Engine light comes on for a catalytic converter code. Replacement is recommended.
Periodic visual inspections of the converters can help spot potential issues early. Signs include blocked flow, rattling, and visible damage.
Aftermarket replacement converters typically have a shorter 50,000-80,000-mile lifespan. OEM parts tend to last longer.

How To Replace Jaguar XJS Catalytic Converters

Positioning:

It uses multiple catalytic converters, one on each exhaust manifold bank. The new converters must be bolted into the original mounting positions for proper exhaust flow.

Exhaust Seals:

When installing the Jaguar XJS Catalytic Converters, use new gaskets to seal the inlet and outlet flanges. Apply high-temperature silicone sealant as well to prevent leaks.

Oxygen Sensors:

Carefully detach and reattach the oxygen sensors from the old converters to the new ones. Position the upstream and downstream sensors properly.

Inspect Other Components:

Inspect the exhaust manifolds, mounts, and pipes when replacing the Jaguar XJS Catalytic Converters. Look for any leaks or damage that needs addressing.

Post-Installation Check:

After installing the new Jaguar XJS Catalytic Converters, clear any codes and road-test the vehicle. Verify the catalyst efficiency monitors are set to ready and that no check engine lights return.