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When a catalytic converter has truly failed, or a thief has cut it out overnight, Route 66 Auto Repair in Upland replaces it and repairs the damage around it. We confirm the right part for your vehicle, explain your options in writing, and fix the cause of the failure so the new converter lasts. California-compliant parts are required where applicable, and we check fitment before you approve anything.
When is converter replacement the right call?
- Testing shows the core is clogged, melted or broken apart
- The shell is cracked or rusted through
- The converter was stolen or cut
- Pieces of core are rattling loose and could block the muffler
What happens after a converter theft?
You start the car and it roars like a dragster. It is a sinking feeling, and the first question is whether it is safe to drive. A short, slow trip is usually possible, but gas now exits under the car, so keep the windows down and do not idle in a closed space. A tow-in is the safer choice, and our after-hours key drop helps when you are stuck at night.
Thieves rarely cut cleanly. We inspect the cut pipe ends, the oxygen sensors and their wiring, nearby heat shields and any brake or fuel lines near the saw marks. The written estimate lists every damaged part, and the photos help if you file an insurance claim.

Which replacement converter fits your car?
California-compliant parts are required where applicable, and the correct part depends on your exact vehicle and its engine. Direct-fit converters bolt in where the original was. Other installs need the converter joined into the existing pipe, and your written estimate shows every step. We explain the parts that fit before you approve, and we will not install a converter that does not belong on your vehicle.
Our converter replacement process
Step 1: Confirm the failure
We verify the diagnosis or document the theft damage with photos.
Step 2: Fix the cause
Misfires, oil burning or sensor faults go on the estimate first, so the new part is not ruined.
Step 3: Match the part
We confirm a compliant converter for your vehicle and quote it in writing.
Step 4: Install and verify
We fit the converter with new gaskets and hardware, check sensor readings, leak-check and road-test.
What's included in converter replacement
Included on the work order
- 01Diagnosis or theft damage review with photos
- 02Part fitment check for your vehicle
- 03New gaskets, studs or clamps at the joints
- 04Oxygen sensor and wiring inspection
- 05Heat shield refit or replacement as quoted
- 06Leak check, code check and road test
Can converter replacement wait?
Need now: call
- A stolen converter with gas exiting under the cabin
- A core blocking flow and choking power
Need later: book
- A steady efficiency code after the cause is fixed, planned within your budget
How pricing and timing work
Converters vary widely in price by vehicle, and theft repairs can add pipe, sensors and wiring, so we quote only after inspection. AAA members get 10% off parts and labor, up to $75. Some converters must be ordered, and we give you a realistic window and text if it slips. Warranty terms depend on the part and are written on the invoice. For testing before replacement, see catalytic converter service.
Frequently asked questions
Why does California have special rules for converters?
California sets its own requirements for replacement converters, and the right part depends on your vehicle. We check what applies to your car and quote only parts that fit it.
Will a new converter fix my check engine light?
Only if the converter was the real fault and the cause is fixed. Otherwise the new one can fail the same way. That is why we test first and check the oxygen sensors and misfire history.
Is it safe to drive after my converter was stolen?
A short, slow drive is usually possible, but exhaust exits under the car and can reach the cabin. Keep windows open, avoid idling, and consider a tow-in. Our exhaust pipe replacement work often goes with a theft repair.
