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Fuel tank service deals with what is inside the tank: stale gas from a car that sat for months, water or rust, debris, the wrong fuel pumped in, or a fuel gauge that reads wrong because of the sending unit. Route 66 Auto Repair in Upland drains and inspects the tank, cleans or replaces what is contaminated, and protects the pump and injectors downstream. You get a written estimate before work starts.
When does a fuel tank need service?
- A car, truck or classic that sat for months with fuel in it
- Diesel pumped into a gas car, or gas into a diesel
- Water or rust found in a fuel filter
- Sputtering that started right after a fill-up
- A fuel gauge that sticks, jumps or reads empty when full
- Varnish smell from the filler on a stored vehicle
What should you do if you put the wrong fuel in?
Do not start the engine. If it is already running, shut it off as soon as it is safe. The less the wrong fuel circulates, the smaller the job. Call us and arrange a tow-in rather than driving over.
Once the car is here, we drain the tank, flush the lines, replace the filter and check how far the fuel traveled. If the engine ran on it, we check for misfires and injector trouble before sending it home.
Our fuel tank service process
Step 1: Sample the fuel
We draw a sample into a clear container so you can see the water, rust or color.
Step 2: Drain and access
The tank is drained into approved containers and the pump module is accessed or the tank lowered.
Step 3: Clean and inspect
We clean out sediment, inspect the pump strainer and sending unit, and photograph the inside when we can see it.
Step 4: Replace contaminated parts
Filters, strainers or the sending unit are replaced as quoted, and lines are flushed where needed.
Step 5: Refill and verify
Fresh fuel goes in, we check pressure and gauge readings, and we road test.
What's included in fuel tank service
Included on the work order
- 01Fuel sample in a clear container
- 02Tank drain and approved disposal
- 03Sediment cleaning and pump strainer check
- 04Sending unit and fuel gauge test
- 05Fuel filter replacement as quoted
- 06Pressure check and road test
Need-now or need-later?
Need now: call
- Wrong fuel in the tank
- Water in the fuel with stalling or misfires
Need later: book
- A gauge that reads a little low but moves
- Old fuel in a stored vehicle you are not driving yet
How pricing and timing work
The work depends on how the tank is accessed. Some cars have a service port under the rear seat, while others require lowering the tank. Fuel disposal and the number of parts that were contaminated also change the total. Phone quotes are ranges until we sample the fuel. AAA members get 10% off parts and labor, up to $75. Tow-ins and after-hours key drop are available.
Aftercare
Run the next tank or two from a busy station. If the car will sit again, ask us about storing it with a full tank to limit condensation. Stored classics often need more than fuel, and our general auto repair team can check the brakes, tires and belts too. If a leak shows up instead, see fuel tank repair. Persistent stumbling after service may call for fuel injector cleaning.
Frequently asked questions
How do I know if my gas has gone bad?
Old gas smells sour or like varnish and may look darker than fresh fuel. The engine may crank long, run rough or stall. We sample it so you can see it before any work is approved.
Why is my fuel gauge wrong?
Most often the sending unit inside the tank is worn or corroded. Sometimes the wiring or the gauge itself is at fault. We test the sender's signal before replacing it, and our electrical system diagnostics team handles wiring faults.
Do fuel additives clean the tank?
Additives can help with light deposits and stabilize fuel for storage. They cannot remove water, rust flakes or sediment. Those need to be drained out.