A car that idles rough after refueling most commonly has a stuck-open EVAP purge valve. The valve can allow excessive gasoline vapor—or even liquid fuel from an overfilled charcoal canister—into the intake, making the air-fuel mixture temporarily too rich. Other possibilities include contaminated fuel, a loose fuel cap, an EVAP vent problem, weak ignition components, or a fuel-delivery fault.
The timing matters. If the engine runs normally before getting gas, then becomes hard to start, shakes, stalls, or smells rich immediately afterward, begin with the evaporative-emissions system. The gas station probably didn’t magically wear out all four spark plugs during the receipt-printing process.
- Hard start and rough idle immediately after filling: A leaking EVAP purge valve is the leading suspect.
- Problem began after topping off the tank: The charcoal canister may be fuel-saturated.
- Rough running continues at all speeds: Check fuel quality, ignition, fuel pressure, and engine-performance faults.
- The Check Engine light appeared after refueling: Scan for EVAP, rich-mixture, lean-mixture, or misfire codes.
- Strong raw-fuel odor or visible leak: Shut the engine off and address the safety hazard before diagnosing anything else.
Quick Diagnosis: Rough Idle After Getting Gas
| What happens | Likely causes |
|---|---|
| Long crank, then rough idle after every fill-up | Purge valve stuck open |
| Engine starts better with accelerator partly depressed | Excess vapor creating a rich mixture |
| Rough idle began after repeatedly topping off | Saturated charcoal canister |
| Check Engine light with P0441 or P0496 | Incorrect or excessive purge flow |
| Rough idle plus P0300–P0308 | Misfire caused by rich mixture, ignition, injector, or compression fault |
| Car runs poorly on the road after one particular fill-up | Contaminated or incorrect fuel |
| Hissing at the filler or pump repeatedly clicks off | Tank venting or filler-neck problem |
| Fuel smell near the rear of the vehicle | Fuel leak, canister saturation, vent or filler problem |
| Fuel smell strongest under the hood | Purge hose, injector, fuel rail, or supply leak |
| Rough idle clears after several minutes | Excess fuel vapor is being consumed |
| Problem occurs even without refueling | Broader ignition, airflow, fuel, or mechanical problem |
| Vehicle stalls and won’t restart | Severe rich condition, fuel fault, or unrelated no-start problem |
This table points you toward the right system. It does not authorize replacing every EVAP component alphabetically until the symptom gets bored and leaves.
Why Refueling Can Affect Engine Idle
Gasoline continuously produces vapor. Instead of releasing those vapors into the atmosphere, the evaporative-emissions system stores them in a charcoal canister. When operating conditions are appropriate, the engine computer opens the purge valve and draws the stored vapor into the intake manifold to be burned.
The system normally includes:
- Fuel tank
- Fuel cap or capless filler seal
- Vapor lines
- Charcoal canister
- Canister vent valve
- Purge-control valve or solenoid
- Fuel-tank pressure sensor
- Engine-control module
During refueling, displaced vapor moves through the tank’s venting system toward the charcoal canister. If the purge valve leaks while the engine is off, vapor can travel into the intake. When the engine starts, that concentrated vapor creates a richer mixture than the computer expects.
A healthy system compensates quickly. A stuck valve, saturated canister, restricted vent, or inaccurate sensor can overwhelm that correction and produce rough idle, hard starting, or stalling.
1. EVAP Purge Valve Stuck Open
The purge valve is the most common cause of rough idle immediately after refueling. It should remain closed when the engine is off and carefully meter vapor while the engine runs. If it sticks open or leaks internally, intake vacuum can pull excessive vapor from the canister and fuel tank.
Common symptoms include:
- Extended cranking after getting gas
- Rough idle immediately after starting
- Engine starts and stalls
- RPM drops or hunts
- Gasoline odor from the exhaust
- Temporary black smoke on some vehicles
- Rich fuel trims immediately after startup
- Misfire codes
- EVAP flow codes
- Normal operation after the excess vapor is burned
Relevant diagnostic codes may include:
- P0441: Incorrect EVAP purge flow
- P0496: EVAP flow during a non-purge condition
- P0172/P0175: System too rich
- P0300–P0308: Random or cylinder-specific misfires
Code definitions and test procedures vary by manufacturer. Some vehicles use different terminology or monitor the same failure indirectly.
How a purge valve is tested
A purge valve should be checked according to the manufacturer’s procedure. Testing may include:
- Commanding the valve with a scan tool
- Monitoring commanded purge percentage
- Watching fuel trims as purge is enabled and disabled
- Checking whether the valve seals when unpowered
- Applying controlled vacuum to the valve
- Verifying power, ground, and control wiring
- Inspecting purge hoses for liquid fuel
An unpowered valve that freely passes air when it should be closed is usually defective. However, verify the plumbing and valve design before declaring victory. Some systems operate differently, because universal simplicity would apparently violate an automotive engineering treaty.
2. Saturated Charcoal Canister From Topping Off
The charcoal canister is designed to store fuel vapor, not liquid gasoline. Continuing to add fuel after the pump automatically shuts off can force liquid fuel into vapor lines and the canister.
Possible symptoms include:
- Rough idle after refueling
- Difficult starting
- Strong fuel odor
- EVAP codes
- Fuel leaking from a vent line
- Premature pump shutoff during later fill-ups
- Damaged purge or vent valve
- Reduced canister capacity
One accidental extra click may not immediately ruin the system, but routinely rounding the purchase up to the nearest satisfying number increases the risk. Stop filling when the nozzle shuts off automatically.
If liquid fuel reaches the purge line, the engine can receive much more fuel than expected. Inspect the hoses and canister rather than replacing only the purge valve and leaving its gasoline-soaked accomplice in place.
3. Contaminated Fuel
If rough running begins after a specific fuel purchase and continues beyond the first few minutes, the gasoline itself may be contaminated.
Possible contaminants include:
- Water
- Diesel fuel
- Dirt or rust
- Excessive ethanol
- Incorrect fuel blend
- Old or degraded gasoline
Symptoms can include:
- Rough idle
- Misfires at all engine speeds
- Hesitation
- Lack of power
- Stalling
- Hard starting
- Check Engine light
- Unusual exhaust odor
Water contamination may cause intermittent misfires as water reaches the fuel pickup. A significant quantity of diesel in a gasoline vehicle can create smoke, plug fouling, and severe running problems. Gasoline in a diesel vehicle can damage the high-pressure fuel system and should be treated as an immediate no-drive condition.
Save the fuel receipt and note the pump number, station, grade, and time. If several vehicles experience similar symptoms after using the same station, report it promptly. A fuel sample can be inspected for separation and contamination using safe, approved procedures.
Do not drain fuel casually into open containers or attempt amateur chemistry beside an ignition source. Gasoline vapor has very little respect for confidence.
4. Incorrect Fuel Grade or Fuel Type
Using a lower octane than recommended usually doesn’t cause an immediate rough idle in a modern gasoline engine, although it can reduce performance and cause spark knock under load. Using the wrong fuel type is much more serious.
Examples include:
- Diesel added to a gasoline vehicle
- Gasoline added to a diesel vehicle
- E85 used in a vehicle that isn’t flex-fuel compatible
- Very high ethanol content in an incompatible fuel system
- Leaded or otherwise unsuitable racing fuel damaging emissions components
If the wrong fuel was added and the engine hasn’t been started, leave it off and arrange professional draining. Starting the engine circulates the fuel through more of the system and converts an inconvenient mistake into a group project involving pumps, rails, injectors, and invoices.
5. EVAP Vent Valve or Restricted Vent System
The canister vent valve allows filtered outside air into the EVAP system. A stuck-closed valve, obstructed filter, kinked hose, or saturated canister can prevent the fuel tank from venting normally.
Possible clues include:
- Fuel nozzle repeatedly clicks off
- Filling the tank takes unusually long
- Pressure or vacuum releases when opening the cap
- Fuel tank appears distorted
- EVAP leak or vent codes
- Fuel odor
- Rough running after refueling
A vent restriction doesn’t always directly cause rough idle, but it can disrupt vapor management and contribute to canister or purge problems. Common vent-related codes include P0446, P0451, P0452, P0453, and manufacturer-specific faults.
Inspect the vent filter for dirt, dust, spider webs, mud, and corrosion—especially on vehicles driven off-road or in areas where road debris treats underbody components as a buffet.
6. Loose, Damaged, or Incorrect Fuel Cap
A loose cap commonly triggers an EVAP leak code. By itself, it usually does not cause an engine to idle severely rough immediately after refueling.
Still, inspect for:
- Loose installation
- Damaged sealing O-ring
- Cracked cap
- Debris on the sealing surface
- Rust or damage at the filler neck
- Incorrect aftermarket cap
- Failed capless-filler flap or seal
Codes such as P0440, P0455, P0456, or P0457 may indicate an EVAP leak, depending on the vehicle.
Tightening the cap may stop a leak, but the warning light might remain on until the computer completes several successful self-tests. A loose cap also shouldn’t be used to explain away hard starting and rich running after every fill-up. That pattern still points more strongly toward purge flow.
7. Damaged EVAP Hose or Vapor Line
Cracked, disconnected, pinched, or incorrectly routed EVAP hoses can produce vapor leaks or allow unintended flow.
Inspect lines between:
- Fuel tank and charcoal canister
- Canister and vent valve
- Canister and purge valve
- Purge valve and intake manifold
Possible symptoms include:
- Fuel odor
- Check Engine light
- Rough idle
- Lean fuel trims from an intake-side leak
- Hard starting after refueling
- Failed emissions inspection
A hose disconnected near the intake can behave like a vacuum leak. A restriction or collapse nearer the tank can interfere with venting. A smoke test is often more effective than looking at several meters of dark hose and asking it to reveal its emotional damage.
8. Leaking Fuel Injector
A fuel injector that leaks after shutdown can flood a cylinder or make the mixture too rich during restart. Refueling may be coincidental, but the extra cranking time at the gas station can make the pattern seem connected.
Possible symptoms include:
- Hard warm restart
- Rough idle after restarting
- Fuel smell
- Black exhaust smoke
- Cylinder-specific misfire
- Oil that smells like gasoline
- Fuel pressure dropping rapidly after shutdown
- Poor fuel economy
Tests may include fuel-pressure leak-down, injector balance, borescope inspection, spark-plug comparison, and electrical testing. Do not assume that injector-cleaning additive will repair a mechanically leaking injector. The bottle is optimistic; physics remains unconvinced.
9. Weak Spark Plugs or Ignition Coils
An overly rich mixture after refueling requires a strong spark to ignite reliably. Worn plugs, excessive plug gap, weak coils, damaged wires, or oil-contaminated plug wells may misfire during the temporary rich condition.
Possible clues include:
- Flashing Check Engine light
- P0300 or cylinder-specific misfire codes
- Shaking that continues beyond refueling
- Misfire under acceleration
- Rough idle in damp weather
- Worn or fouled spark plugs
The EVAP system may trigger the event while weak ignition makes it more severe. Diagnose both sides when purge control is faulty and one cylinder consistently records most of the misfires.
10. Dirty Throttle Body or Airflow Problem
Carbon around the throttle plate can reduce the system’s ability to stabilize idle when the mixture suddenly changes. A contaminated mass airflow sensor, cracked intake boot, restricted air filter, or vacuum leak can produce similar problems.
Symptoms may include:
- Low or hunting idle
- Stalling when coming to a stop
- Hesitation
- Fuel-trim codes
- Poor throttle response
- Rough running unrelated to refueling
Inspect the intake tract and review airflow data before cleaning or replacing components. Some electronic throttle bodies require an idle relearn after cleaning or battery disconnection.
11. Fuel-Pressure Problem
A weak pump, faulty pressure regulator, restricted filter, pump-control module, or electrical fault can cause rough idle after the engine is restarted.
Possible symptoms include:
- Long crank at any fuel level
- Hesitation under load
- Stalling
- Lean codes
- Loss of power uphill
- Fuel pressure outside specification
Fuel level can affect some failing pumps. A vehicle may run differently with a full tank because the pump is cooled differently, the tank changes shape, or a damaged pickup or internal hose behaves differently.
Test pressure, volume, electrical supply, and pressure retention under the conditions that reproduce the complaint. Hearing the pump prime proves that it produces sound. Your children can do that too; nobody calls them a fuel-delivery system.
12. Fuel-Tank Pressure Sensor Fault
The fuel-tank pressure sensor reports pressure and vacuum inside the tank. The engine computer uses that information during EVAP leak testing and purge control.
An inaccurate signal may cause:
- EVAP monitor failures
- Incorrect purge behavior
- Check Engine light
- Implausible tank-pressure readings
- Refueling difficulty
Codes may include P0451, P0452, or P0453. Compare the sensor reading with atmospheric pressure when appropriate and follow the manufacturer’s electrical test. A code identifying a circuit doesn’t guarantee the sensor is bad; wiring, connectors, reference voltage, and ground also receive invitations to the diagnostic party.
13. PCV Valve or Vacuum Leak
A stuck PCV valve, cracked PCV hose, brake-booster leak, or intake-manifold gasket failure can destabilize idle. Refueling may temporarily intensify the problem when the purge system adds another airflow and vapor change.
Clues include:
- High or unstable idle
- Hissing noise
- Strong positive fuel trims
- Lean codes P0171 or P0174
- Oil leaks or excessive crankcase vacuum
- Rough idle that improves at higher RPM
Compare fuel trims at idle and at increased RPM. A large positive correction at idle that improves as airflow rises often supports a vacuum leak.
14. EVAP System Software or Control Fault
Some symptoms arise from calibration, wiring, connector, or control-module problems rather than a mechanically stuck valve.
Potential causes include:
- Shorted purge-control circuit
- Damaged wiring near the engine
- Corroded connector
- Incorrect replacement valve
- Control-module driver fault
- Manufacturer software update or service bulletin
Verify commanded purge against actual flow. A valve can be mechanically healthy but continuously commanded open because the signal or control strategy is wrong. Conversely, the scan tool may show zero commanded purge while a leaking valve passes vapor anyway.
Why Is My Car Hard to Start After Getting Gas?
A hard start immediately after refueling is the classic symptom of excessive purge flow. Concentrated fuel vapor enters the intake and creates a temporarily rich mixture.
The engine may:
- Crank longer than normal
- Start only with the accelerator slightly open
- Start and stall
- Run rough for 10–60 seconds
- Smell strongly of gasoline
- Recover and drive normally afterward
Opening the throttle may introduce more air, which helps a flooded engine start. This observation is a diagnostic clue, not a daily workaround. Holding the accelerator to the floor can also activate clear-flood mode on some fuel-injected vehicles, but behavior varies by manufacturer.
Repeatedly using pedal position to overcome the fault doesn’t repair the purge valve. It simply teaches the owner a strange ritual every time the fuel gauge reaches empty.
Why Does My Car Stall After Refueling?
If excessive vapor makes the mixture too rich, combustion can become unstable enough for the engine to stall. A purge valve stuck wide open may also act like a vacuum leak once vapor concentration changes.
Other causes include:
- Saturated charcoal canister
- Contaminated fuel
- Leaking injector
- Weak ignition
- Dirty throttle body
- Incorrect fuel
- Fuel-pressure failure
If the vehicle stalls in the station, move it only if doing so is safe. Shut it off immediately if fuel is leaking, smoke is present, or the odor is severe.
Why Does the Check Engine Light Come On After Getting Gas?
The EVAP monitor may detect a leak, incorrect flow, or pressure that doesn’t respond as expected. The light may appear shortly after refueling or several drive cycles later.
Common code families include:
- P0440: General EVAP system malfunction
- P0441: Incorrect purge flow
- P0442: Small EVAP leak
- P0446: Vent-control circuit or performance
- P0455: Large EVAP leak
- P0456: Very small EVAP leak
- P0457: Fuel-cap-related leak on some vehicles
- P0496: Purge flow during a non-purge condition
Retrieve the exact code and freeze-frame data. “EVAP code” isn’t a complete diagnosis any more than “engine noise” is a repair estimate.
How to Diagnose Rough Idle After Refueling
Step 1: Record the Exact Pattern
Note:
- Whether the tank was nearly empty
- How much fuel was added
- Whether the tank was topped off
- Fuel grade and station
- Cranking time
- Whether opening the throttle helped
- Duration of the rough idle
- Fuel odor, smoke, or leakage
- Warning-light behavior
- Whether the symptom occurs after every fill-up
A repeatable event immediately after refueling strongly favors the EVAP purge system.
Step 2: Check for an Immediate Fuel Leak
Before connecting diagnostic equipment, inspect for dripping fuel, wet areas, strong concentrated odor, or damaged filler components.
Do not start or continue running the engine around a visible leak. Avoid sparks, smoking, switches, and other ignition sources. Arrange professional assistance.
Step 3: Scan All Relevant Codes
Record stored, pending, permanent, and manufacturer-specific codes before clearing anything.
Review:
- Freeze-frame data
- Short- and long-term fuel trims
- Misfire counts
- Commanded purge
- Fuel-tank pressure
- Oxygen or air-fuel sensor data
- MAF readings
- Engine coolant temperature
Clearing the codes first erases clues. It also creates the delightful possibility of paying someone to reproduce the exact evidence you just deleted.
Step 4: Inspect the Fuel Cap and Filler Area
Confirm that the cap is correct, secure, and undamaged. Inspect capless filler seals, the filler neck, and visible vent connections.
Remember that a loose cap commonly causes a leak code but rarely explains a severe rich start after refueling.
Step 5: Test the Purge Valve for Leakage
With the valve unpowered and expected to be closed, verify whether it seals. Follow vehicle-specific procedures and flow direction.
If it leaks, inspect the purge hose for liquid fuel and evaluate the charcoal canister. Replacing a valve without finding why it was exposed to liquid fuel can shorten the replacement’s life.
Step 6: Command Purge and Watch Fuel Trims
With a capable scan tool, compare commanded purge, fuel trims, idle quality, and tank-pressure response.
Fuel trims that swing sharply negative when purge flow begins may indicate excessive fuel vapor. No response may indicate a blocked line, stuck-closed valve, saturated sensor signal, or lack of vapor.
Interpret data using manufacturer specifications and current operating conditions.
Step 7: Smoke-Test the EVAP System
An approved low-pressure smoke machine can locate leaks at hoses, valves, the canister, cap, filler neck, or tank connections.
Use equipment and pressure designed for EVAP testing. Shop air at enthusiastic pressure can damage the system and introduce an ignition hazard—two failures for the price of one.
Step 8: Check Fuel Quality When Appropriate
If the problem started after a single station visit and continues while driving, inspect a safely obtained fuel sample or have a shop test it.
Do not blame fuel quality solely because the symptom followed refueling. A purge fault follows refueling by definition and is generally more common.
Step 9: Diagnose Misfires and Basic Engine Operation
If the rough idle persists, inspect:
- Spark plugs and ignition coils
- Injector operation
- Fuel pressure
- Intake leaks
- Throttle body
- Compression
- Engine timing
Refueling may expose an existing weakness without being its root cause.
Can I Drive With a Rough Idle After Refueling?
A brief mild rough idle that clears may not require an emergency tow, but repeated hard starting or stalling should be repaired. Uncontrolled vapor flow can increase emissions, damage the charcoal canister, foul spark plugs, dilute engine oil, and overheat the catalytic converter if severe misfires occur.
Stop driving and shut the engine off if:
- Fuel is visibly leaking
- The fuel odor is strong or worsening
- Smoke appears
- The Check Engine light flashes
- The engine stalls in traffic
- The vehicle won’t maintain safe power
- The wrong fuel was added
- The engine knocks or makes abnormal mechanical noise
- Fuel is present in the purge or vent lines
A flashing Check Engine light usually indicates an active misfire capable of damaging the catalytic converter. Reduce load, pull over safely, and arrange diagnosis.
How Much Does It Cost to Fix Rough Idle After Refueling?
Cost depends on the vehicle, access, and failed component. Possible repairs range from a correctly installed fuel cap or damaged hose to purge-valve, vent-valve, charcoal-canister, injector, or fuel-system work.
The efficient sequence is:
- Confirm the symptom pattern.
- Scan and record codes and data.
- Test whether the purge valve seals.
- Inspect for liquid fuel and canister saturation.
- Smoke-test or pressure-test the system as required.
- Test fuel quality and basic engine systems only when the evidence points there.
Replacing the cap, purge valve, vent valve, pressure sensor, and canister all at once may eventually fix the problem. So would replacing the car. Neither qualifies as diagnosis.
How to Prevent EVAP Problems After Refueling
- Stop filling when the pump nozzle automatically shuts off.
- Don’t repeatedly top off the tank.
- Use the fuel grade and type specified by the manufacturer.
- Replace a missing or damaged cap with the correct part.
- Keep dirt away from capless filler seals.
- Address EVAP warning codes before canister or valve damage spreads.
- Investigate repeated pump shutoff rather than forcing more fuel into the tank.
- Keep receipts when fuel contamination is suspected.
The nozzle’s first click is the finish line, not the opening bid.
Frequently Asked Questions
What is the most common cause of rough idle after getting gas?
A stuck-open or leaking EVAP purge valve is the most common cause, especially when the engine cranks longer than normal, starts rough, or stalls immediately after filling the tank.
Can a bad purge valve cause rough idle?
Yes. A purge valve stuck open can allow excessive fuel vapor into the intake. It may create a rich mixture after refueling and can act like a vacuum leak under other conditions.
Why does my car start only when I press the gas after refueling?
Opening the throttle adds air and may help overcome an overly rich mixture caused by excess fuel vapor. This strongly suggests purge-valve leakage or a saturated charcoal canister, although testing is still required.
Can topping off the tank cause rough idle?
Yes. Adding fuel after the nozzle shuts off can force liquid gasoline into the charcoal canister and vapor lines. That can cause hard starting, rough idle, fuel odor, and EVAP faults.
Will a loose gas cap make the engine run rough?
Usually not. A loose cap commonly causes an EVAP leak code and Check Engine light, but severe rough idle immediately after filling is more strongly associated with excessive purge flow or fuel contamination.
Why does my car smell like gas after refueling?
A brief odor near the pump may be spilled fuel or displaced vapor. Persistent or strong odor can indicate a leak, overfilled tank, saturated canister, damaged vapor line, faulty cap, leaking injector, or purge-system fault. Visible fuel requires immediate action.
How do I know if my charcoal canister is saturated?
Clues include a history of topping off, liquid fuel in vapor lines, strong odor, refueling difficulty, EVAP codes, and rough starting after fills. The canister and related valves should be tested rather than diagnosed by odor alone.
Can bad gas cause rough idle immediately?
Yes. Water, incorrect fuel, excessive ethanol, or other contamination can cause misfires and rough running. Unlike a purge fault that often clears, contaminated fuel may cause symptoms during acceleration and cruising as well.
Why does my car run rough only for 30 seconds after getting gas?
The engine may be consuming excess fuel vapor drawn into the intake through a leaking purge valve. Once the mixture stabilizes, idle returns to normal. The short duration is a useful clue, not proof that the problem fixed itself.
Can a purge valve fail without a Check Engine light?
Yes. A valve may leak intermittently or not exceed the monitor’s failure threshold. Pending codes, fuel-trim changes, and a physical sealing test may reveal the problem before the warning light appears.
Can I temporarily disconnect the purge valve?
Disconnecting hoses or electrical connectors can create vacuum leaks, EVAP codes, uncontrolled vapor release, or other drivability problems. Test and repair the system according to the manufacturer’s procedure instead.
Why does the gas pump keep clicking off?
A restricted vent valve, clogged vent filter, saturated charcoal canister, damaged filler neck, or nozzle-position issue can prevent vapor from leaving the tank normally. Repeatedly forcing fuel in can worsen the problem.
Does premium fuel fix rough idle after refueling?
No. Higher octane doesn’t repair a leaking purge valve, saturated canister, ignition fault, or contaminated fuel system. Use the octane recommended for the vehicle and diagnose the actual cause.
Can rough idle after refueling damage the catalytic converter?
Severe or repeated rich misfires can send unburned fuel into the converter and overheat it. A flashing Check Engine light is a warning to stop driving normally and address the misfire.
Why did the problem start after replacing my fuel pump?
Inspect recently disturbed tank seals, EVAP lines, electrical connectors, vent routing, filler connections, and pump-module installation. A pinched hose or damaged seal can create new EVAP and fuel-delivery faults.
The Bottom Line
When a car idles rough immediately after refueling, test the EVAP purge valve first. A valve that leaks while closed can fill the intake with fuel vapor, causing long cranking, rich operation, shaking, or stalling until the excess vapor burns away.
Also check whether the tank was topped off, whether liquid fuel reached the charcoal canister, and whether the problem continues while driving. Persistent symptoms after one particular fill-up raise concern for contaminated or incorrect fuel. A loose cap can trigger a warning light, but it usually doesn’t explain severe post-fill rough running by itself.
Record the pattern, scan the codes, inspect for leaks, and verify purge flow before buying parts. The fuel nozzle already took enough money from you. There’s no reason to let the parts cannon finish the job.
