Question about 2001 Ford Focus

3 Answers

Misfire on cylinder 4 only when accelerating

Ford Puma 1.7
Misfires on cylinder 4 when accelerating or engine under load, but just OK at idle and with very gentle accelerator usage. All spark plugs except cylinder 4 have proper colouring. Cylinder 4 bad colouring. Diagnostics software confirmed one fault only: missfire on cylinder 4. Changed plugs, same problem. Visual checked for spark - spark there. Visual inspection of injectors - seem to be spotless. Swapped injector 4 with injector 1. Still problem on cylinder 4. Swapped plug 4 with plug 1. Still problem on cylinder 4. Check resistance of spark leads - seem to be OK (not sure of expected resistance values, but longer leads proportionally show more resistance than shorter ones). Ordered new ignition coil, as I am told these commonly fail. Can't be fuel starvation, as this would affect all cylinders and would show up when at high revs even without load. If not coil, then possibly the engine management computer? No signs of head gasket problems, fluids and oil clean. Any suggestions are very welcome!

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  • carlo210 Jul 18, 2009

    Problem is solved! Replaced the ignition coil pack and engine runs perfectly. The compression test was always high on my list, but the coil pack got delivered before my compression tester! Will probably do a compression test just to see the results. Many thanks to everyone who helped.

  • ahmet ezik Oct 20, 2012

    i had same problem replaced the ignition coil now its good...thanks for sharing this info

  • Anonymous Mar 20, 2014

    plugs replaced. #4 cylinder plug wasn't even screwed in. made sure replscement was. on running got chck engine and testing showed bad #1 coil. Swapped. Engine ran but rough. shut off for 2 minutes. on restart, heard a loud pop followed by high pitched whine. this happens in drive and neutral. swapped starter relay w/pcm relay. still no go

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Coil pack

Posted on May 05, 2010

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Try a compression test. You could have a bent valve or a bad ring on the piston. If the compression test shows it to be much lower than the other cylinders then its a mechanical problem. The valve may not be seating or a weak spring isn't allowing the valves to close and its leaking under load.

Posted on Jul 13, 2009

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Just change ur throttle position sensor and let me know if auto u have to change the hole throttle body they don't dell it seperat good luck

Posted on Aug 12, 2009

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RE: Johnny brown- 2003 Sebring multiple cylinder misfire 3.0 New distributor new crankshaft sensor new plugs new wires good compression injectors good... Installed new EGR started with cold engine and


ENGINE MISFIRE

There are few possibilities that can cause engine misfire issues. It can be issue with spark plugs or faulty spark plugs. Also get the compression test done for cylinders. If any of cylinder shows low compression then required, then that particular cylinder will cause misfire.

Also get obd codes scanned, the error code will let you know which cylinder is misfiring or all cylinders are misfiring.

-----------

For your trouble shooting I suggest you to refer the help oinks below. It has step by step details for many engine misfire issues.

----------


Click the link below:-----


Ford Explorer Cylinder Misfire?

http://whoisbyme.blogspot.in/2012/06/ford-explorer-cylinder-misfire.html

---------

Engine Misfire codes on Chevrolet Malibu?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html

---------

Cylinder 6 Misfire?

http://howtobyme.blogspot.com/2011/12/cylinder-6-misfire.html

------------

Misfire on cylinder 4?

http://schematicsdiagram.blogspot.com/2011/12/misfire-on-cylinder-4.html

-----

While stop engine idles like cylinder missing?

http://schematicsdiagram.blogspot.com/2012/01/while-stop-engine-idles-like-cylinder.html

----------

Ford Explorer 5.0L: Engine Miss?

http://whoisbyme.blogspot.in/2012/06/ford-explorer-50l-engine-miss.html

-----------

Oil on spark plugs and car misfires?

http://technoanswers.blogspot.in/2012/02/oil-on-spark-plugs-and-car-misfires.html

------------

Can cylinder misfire Damage the Catalytic converter?

http://schematicsdiagram.blogspot.in/2012/02/can-cylinder-misfire-damage-catalytic.html

------------

Car misfires and error code P0306 and P0303 is shown?

http://technoanswers.blogspot.com/2012/01/car-misfires-and-error-code-p0306-and.html

-----------

Chevrolet K1500 No spark, random misfire

http://repairhelpcenter.blogspot.com/2012/11/chevrolet-k1500-no-sparkrandom-misfire.html

-------------

2004 Ford F150: Engine Misfire and Lean Code?

http://whatisbyme.blogspot.in/2012/05/2004-ford-f150-engine-misfire-and-lean.html

-----------

1995 Toyota LS: Misfire at idle or low RPM

http://whatisbyme.blogspot.in/2012/04/1995-toyota-ls-misfire-at-idle-or-low.html

--------------

Toyota Corolla: Random Misfire?

http://technoanswers.blogspot.in/2012/04/toyota-corolla-random-misfire.html

----------

2006 Ford Freestar: Misfire on Cylinder Number 2?

http://whatisbyme.blogspot.in/2012/06/2006-ford-freestar-misfire-on-cylinder.html

-----------------------------


This will help.

Thanks.

Dec 09, 2012 | Cars & Trucks

2 Answers

Bad gas mileage from O2 senor being bad, EGR sensor bad or needs cleaning


How to Increase gas mileage?
http://schematicsdiagram.blogspot.com/2011/12/how-to-increase-gas-mileage-on-2011.html---------

For car not changing gears it can be shifter assembly issue, or it can also be transmission issue. Get the shifter assembly inspected with ignition OFF.

For more troubleshooting, I suggest you to get the Following help link checked, its complete step by step procedure to inspect gear shift issues: -----

GEAR SHIFT ISSUES

http://alltypesofpartsreplacing.blogspot.com/2012/11/gear-shift-issues.html

==========




Car not starting or turning over indicates towards multiple possibilities. It can be issue with battery or weak battery. But if battery checks out ok, then it can be starter issue or faulty alternator or problem with low fuel pressure or no spark at spark plugs due to dirty spark plugs or faulty ignition coil or injectors getting cracked or dirty and needs to be cleaned.


To confirm the problem, the basic troubleshooting is required.



From start to end troubleshooting these problems I suggest you to check the help link below and follow its procedure: -----


Mostly all types of car no start problems are discussed here with solutions.


CAR NO START: ENGINE NOT TURNING OVER:
http://alltypesofpartsreplacing.blogspot.com/2012/11/car-no-start-engine-not-turning-over.html
----------




ENGINE MISFIRE

There are few possibilities that can cause engine misfire issues. It can be issue with spark plugs or faulty spark plugs. Also get the compression test done for cylinders. If any of cylinder shows low compression then required, then that particular cylinder will cause misfire.

Also get obd codes scanned, the error code will let you know which cylinder is misfiring or all cylinders are misfiring.

-----------

For your trouble shooting I suggest you to refer the help oinks below. It has step by step details for many engine misfire issues.

----------


Click the link below:-----


Ford Explorer Cylinder Misfire?

http://whoisbyme.blogspot.in/2012/06/ford-explorer-cylinder-misfire.html

---------

Engine Misfire codes on Chevrolet Malibu?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html

---------

Cylinder 6 Misfire?

http://howtobyme.blogspot.com/2011/12/cylinder-6-misfire.html

------------

Misfire on cylinder 4?

http://schematicsdiagram.blogspot.com/2011/12/misfire-on-cylinder-4.html

-----

While stop engine idles like cylinder missing?

http://schematicsdiagram.blogspot.com/2012/01/while-stop-engine-idles-like-cylinder.html

----------

Ford Explorer 5.0L: Engine Miss?

http://whoisbyme.blogspot.in/2012/06/ford-explorer-50l-engine-miss.html

-----------

Oil on spark plugs and car misfires?

http://technoanswers.blogspot.in/2012/02/oil-on-spark-plugs-and-car-misfires.html

------------

Can cylinder misfire Damage the Catalytic converter?

http://schematicsdiagram.blogspot.in/2012/02/can-cylinder-misfire-damage-catalytic.html

------------

Car misfires and error code P0306 and P0303 is shown?

http://technoanswers.blogspot.com/2012/01/car-misfires-and-error-code-p0306-and.html

-----------

Chevrolet K1500 No spark, random misfire

http://repairhelpcenter.blogspot.com/2012/11/chevrolet-k1500-no-sparkrandom-misfire.html

-------------

2004 Ford F150: Engine Misfire and Lean Code?

http://whatisbyme.blogspot.in/2012/05/2004-ford-f150-engine-misfire-and-lean.html

-----------

1995 Toyota LS: Misfire at idle or low RPM

http://whatisbyme.blogspot.in/2012/04/1995-toyota-ls-misfire-at-idle-or-low.html

--------------

Toyota Corolla: Random Misfire?

http://technoanswers.blogspot.in/2012/04/toyota-corolla-random-misfire.html

----------

2006 Ford Freestar: Misfire on Cylinder Number 2?

http://whatisbyme.blogspot.in/2012/06/2006-ford-freestar-misfire-on-cylinder.html

-----------------------------


This will help.

Thanks.

Dec 06, 2012 | 1997 Mitsubishi Eclipse

1 Answer

Ck engine light is on and miss fire #5


There are few possibilities that can cause engine misfire issues. It can be issue with spark plugs or faulty spark plugs. Also get the compression test done for cylinders. If any of cylinder shows low compression then required, then that particular cylinder will cause misfire.

Also get obd codes scanned, the error code will let you know which cylinder is misfiring or all cylinders are misfiring.

-----------

For your trouble shooting I suggest you to refer the help oinks below. It has step by step details for many engine misfire issues.

----------


Click the link below:-----


Ford Explorer Cylinder Misfire?

http://whoisbyme.blogspot.in/2012/06/ford-explorer-cylinder-misfire.html

---------

Engine Misfire codes on Chevrolet Malibu?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html

---------

Cylinder 6 Misfire?

http://howtobyme.blogspot.com/2011/12/cylinder-6-misfire.html

------------

Misfire on cylinder 4?

http://schematicsdiagram.blogspot.com/2011/12/misfire-on-cylinder-4.html

-----

While stop engine idles like cylinder missing?

http://schematicsdiagram.blogspot.com/2012/01/while-stop-engine-idles-like-cylinder.html

----------

Ford Explorer 5.0L: Engine Miss?

http://whoisbyme.blogspot.in/2012/06/ford-explorer-50l-engine-miss.html

-----------

Oil on spark plugs and car misfires?

http://technoanswers.blogspot.in/2012/02/oil-on-spark-plugs-and-car-misfires.html

------------

Can cylinder misfire Damage the Catalytic converter?

http://schematicsdiagram.blogspot.in/2012/02/can-cylinder-misfire-damage-catalytic.html

------------

Car misfires and error code P0306 and P0303 is shown?

http://technoanswers.blogspot.com/2012/01/car-misfires-and-error-code-p0306-and.html

-----------

Chevrolet K1500 No spark, random misfire

http://repairhelpcenter.blogspot.com/2012/11/chevrolet-k1500-no-sparkrandom-misfire.html

-------------

2004 Ford F150: Engine Misfire and Lean Code?

http://whatisbyme.blogspot.in/2012/05/2004-ford-f150-engine-misfire-and-lean.html

-----------

1995 Toyota LS: Misfire at idle or low RPM

http://whatisbyme.blogspot.in/2012/04/1995-toyota-ls-misfire-at-idle-or-low.html

--------------

Toyota Corolla: Random Misfire?

http://technoanswers.blogspot.in/2012/04/toyota-corolla-random-misfire.html

----------

2006 Ford Freestar: Misfire on Cylinder Number 2?

http://whatisbyme.blogspot.in/2012/06/2006-ford-freestar-misfire-on-cylinder.html

-----------------------------


This will help.

Thanks.

Nov 28, 2012 | 1994 Lincoln Town Car

1 Answer

Number 3 and 4 are not firing from coil on 2002 subaru outback 2.5


its faulty coil.

Get the compression test done on each coil.these will let you know if its faulty coil or not.

=========

It can be issue with spark plugs or faulty spark plugs. Also get the compression test done for cylinders. If any of cylinder shows low compression then required, then that particular cylinder will cause misfire.

Also get obd codes scanned, the error code will let you know which cylinder is misfiring or all cylinders are misfiring.

-----------

For your trouble shooting I suggest you to refer the help oinks below. It has step by step details for many engine misfire issues.

----------


Click the link below:-----


Ford Explorer Cylinder Misfire?

http://whoisbyme.blogspot.in/2012/06/ford-explorer-cylinder-misfire.html

---------

Engine Misfire codes on Chevrolet Malibu?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html

---------

Cylinder 6 Misfire?

http://howtobyme.blogspot.com/2011/12/cylinder-6-misfire.html

------------

Misfire on cylinder 4?

http://schematicsdiagram.blogspot.com/2011/12/misfire-on-cylinder-4.html

-----

While stop engine idles like cylinder missing?

http://schematicsdiagram.blogspot.com/2012/01/while-stop-engine-idles-like-cylinder.html

----------

Ford Explorer 5.0L: Engine Miss?

http://whoisbyme.blogspot.in/2012/06/ford-explorer-50l-engine-miss.html

-----------

Oil on spark plugs and car misfires?

http://technoanswers.blogspot.in/2012/02/oil-on-spark-plugs-and-car-misfires.html

------------

Can cylinder misfire Damage the Catalytic converter?

http://schematicsdiagram.blogspot.in/2012/02/can-cylinder-misfire-damage-catalytic.html

------------

Car misfires and error code P0306 and P0303 is shown?

http://technoanswers.blogspot.com/2012/01/car-misfires-and-error-code-p0306-and.html

-----------

Chevrolet K1500 No spark, random misfire

http://repairhelpcenter.blogspot.com/2012/11/chevrolet-k1500-no-sparkrandom-misfire.html

-------------

2004 Ford F150: Engine Misfire and Lean Code?

http://whatisbyme.blogspot.in/2012/05/2004-ford-f150-engine-misfire-and-lean.html

-----------

1995 Toyota LS: Misfire at idle or low RPM

http://whatisbyme.blogspot.in/2012/04/1995-toyota-ls-misfire-at-idle-or-low.html

--------------

Toyota Corolla: Random Misfire?

http://technoanswers.blogspot.in/2012/04/toyota-corolla-random-misfire.html

----------

2006 Ford Freestar: Misfire on Cylinder Number 2?

http://whatisbyme.blogspot.in/2012/06/2006-ford-freestar-misfire-on-cylinder.html

-----------------------------


This will help.

Thanks.

Nov 28, 2012 | Cars & Trucks

1 Answer

Engine is misfiring


There are few possibilities that can cause engine misfire issues. It can be issue with spark plugs or faulty spark plugs. Also get the compression test done for cylinders. If any of cylinder shows low compression then required, then that particular cylinder will cause misfire.

Also get obd codes scanned, the error code will let you know which cylinder is misfiring or all cylinders are misfiring.

-----------

For your trouble shooting I suggest you to refer the help oinks below. It has step by step details for many engine misfire issues.

----------


Click the link below:-----


Ford Explorer Cylinder Misfire?

http://whoisbyme.blogspot.in/2012/06/ford-explorer-cylinder-misfire.html

---------

Engine Misfire codes on Chevrolet Malibu?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html

---------

Cylinder 6 Misfire?

http://howtobyme.blogspot.com/2011/12/cylinder-6-misfire.html

------------

Misfire on cylinder 4?

http://schematicsdiagram.blogspot.com/2011/12/misfire-on-cylinder-4.html

-----

While stop engine idles like cylinder missing?

http://schematicsdiagram.blogspot.com/2012/01/while-stop-engine-idles-like-cylinder.html

----------

Ford Explorer 5.0L: Engine Miss?

http://whoisbyme.blogspot.in/2012/06/ford-explorer-50l-engine-miss.html

-----------

Oil on spark plugs and car misfires?

http://technoanswers.blogspot.in/2012/02/oil-on-spark-plugs-and-car-misfires.html

------------

Can cylinder misfire Damage the Catalytic converter?

http://schematicsdiagram.blogspot.in/2012/02/can-cylinder-misfire-damage-catalytic.html

------------

Car misfires and error code P0306 and P0303 is shown?

http://technoanswers.blogspot.com/2012/01/car-misfires-and-error-code-p0306-and.html

-----------

Chevrolet K1500 No spark, random misfire

http://repairhelpcenter.blogspot.com/2012/11/chevrolet-k1500-no-sparkrandom-misfire.html

-------------

2004 Ford F150: Engine Misfire and Lean Code?

http://whatisbyme.blogspot.in/2012/05/2004-ford-f150-engine-misfire-and-lean.html

-----------

1995 Toyota LS: Misfire at idle or low RPM

http://whatisbyme.blogspot.in/2012/04/1995-toyota-ls-misfire-at-idle-or-low.html

--------------

Toyota Corolla: Random Misfire?

http://technoanswers.blogspot.in/2012/04/toyota-corolla-random-misfire.html

----------

2006 Ford Freestar: Misfire on Cylinder Number 2?

http://whatisbyme.blogspot.in/2012/06/2006-ford-freestar-misfire-on-cylinder.html

-----------------------------


This will help.

Thanks.

Nov 28, 2012 | 2004 Honda CR-V

1 Answer

Cylinder misfire


replace no 2 injector

May 05, 2017 | 2009 Chevrolet Traverse

1 Answer

My 2006 mustang gt misfires under load in higher rpms


For engine misfiring problem check the help links mentioned below. Click the link below to go through the troubleshooting procedure :---- Engine misses and truck jumps? Hard to down shift? Issue with high gear only? http://technoanswers.blogspot.in/2012/02/engine-miss-and-truck-jumps-hard-to.html

-----------
Bad miss at idle?

http://technoanswers.blogspot.com/2012/01/bad-miss-at-idle.html

-----------
While stop engine idles like cylinder missing?

http://schematicsdiagram.blogspot.com/2012/01/while-stop-engine-idles-like-cylinder.html

------------
Engine Misfire codes for car?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html
Engine Misfire codes?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html

--------------
Misfire on cylinder 4?

http://schematicsdiagram.blogspot.com/2011/12/misfire-on-cylinder-4.html

-----------
Oil on spark plugs and car misfires?

http://technoanswers.blogspot.in/2012/02/oil-on-spark-plugs-and-car-misfires.html

----------

This will help.

Thanks.

Feb 28, 2012 | 2006 Ford Mustang

1 Answer

My 2003 mustang has a misfire code P0302 and runs rough under load.


For engine misfiring problem check the help links mentioned below. Click the link below to go through the troubleshooting procedure :---- OBD-II Trouble Code P0300? http://schematicsdiagram.blogspot.com/2011/12/obd-ii-trouble-code-p0300.html
---------- Engine misses and truck jumps? Hard to down shift? Issue with high gear only? http://technoanswers.blogspot.in/2012/02/engine-miss-and-truck-jumps-hard-to.html

-----------
Bad miss at idle?

http://technoanswers.blogspot.com/2012/01/bad-miss-at-idle.html

-----------
While stop engine idles like cylinder missing?

http://schematicsdiagram.blogspot.com/2012/01/while-stop-engine-idles-like-cylinder.html

------------
Engine Misfire codes for car?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html
Engine Misfire codes?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html

--------------
Misfire on cylinder 4?

http://schematicsdiagram.blogspot.com/2011/12/misfire-on-cylinder-4.html

-----------
Oil on spark plugs and car misfires?

http://technoanswers.blogspot.in/2012/02/oil-on-spark-plugs-and-car-misfires.html

----------

This will help.

Thanks.

Feb 13, 2012 | 2003 Ford Mustang

1 Answer

P0303 cylinder misfire


For engine misfiring problem check the help links mentioned below. Click the link below to go through the troubleshooting procedure :---- OBD-II Trouble Code P0300? http://schematicsdiagram.blogspot.com/2011/12/obd-ii-trouble-code-p0300.html
---------Car misfires and error code P0306 and P0303 is shown? http://technoanswers.blogspot.com/2012/01/car-misfires-and-error-code-p0306-and.html
-----------
Engine misses and truck jumps? Hard to down shift? Issue with high gear only? http://technoanswers.blogspot.in/2012/02/engine-miss-and-truck-jumps-hard-to.html

-----------
Bad miss at idle?

http://technoanswers.blogspot.com/2012/01/bad-miss-at-idle.html

-----------
While stop engine idles like cylinder missing?

http://schematicsdiagram.blogspot.com/2012/01/while-stop-engine-idles-like-cylinder.html

------------
Engine Misfire codes for car?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html
Engine Misfire codes?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html

--------------
Misfire on cylinder 4?

http://schematicsdiagram.blogspot.com/2011/12/misfire-on-cylinder-4.html

-----------
Oil on spark plugs and car misfires?

http://technoanswers.blogspot.in/2012/02/oil-on-spark-plugs-and-car-misfires.html

----------

This will help.

Thanks.

Jan 23, 2012 | 1999 Subaru Legacy

1 Answer

I am having ongoing problems with the truck miss firing and rough running. Timing is ok, replaced cap and rotor,coil. It still starts rough,idles rough and misses when at cruising speed,although it seems...


Misfire is a common driveability problem that may or may not be easy to diagnose, depending on the cause. A misfiring cylinder in a four-cylinder engine is, pardon the pun, hard to miss. The loss of 25% of the engine's power output is the equivalent of a horse trying to run on three legs. The engine may shake so badly at idle that it causes vibrations that can be felt in the steering wheel and throughout the vehicle. The engine also may be hard to start and may even stall at idle, depending on the accessory load (air conditioning, headlights and electric rear defroster, for example).

When misfire occurs, performance suffers along with fuel economy, emissions and idle quality. And, when a misfiring vehicle is subjected to an emissions test, it will usually fail because of the unusually high levels of hydrocarbons (HC) in the exhaust.

What causes a cylinder to misfire? Basically, it's one of three things: loss of spark; the air/fuel mixture is too far out of balance to ignite; or loss of compression. Loss of spark includes anything that prevents coil voltage from jumping the electrode gap at the end of the spark plug. Causes include worn, fouled or damaged spark plugs, bad spark plug wires or even a cracked distributor cap. A weak coil or excessive rotor gas inside a distributor would affect all cylinders, not just a single cylinder.

"Lean misfire" can occur when the air/fuel mixture is too lean (not enough gasoline in the mixture) to burn. This can be caused by a dirty, clogged or inoperative fuel injector; air leaks; or low fuel pressure because of a weak pump, restricted filter or leaky pressure regulator. Low fuel pressure would affect all cylinders rather than an individual cylinder, as would most air leaks. A leaky EGR valve can also have the same effect as an air leak.

Loss of compression means the cylinder loses most of its air/fuel mixture before it can be ignited. The most likely causes here are a leaky (burned) exhaust valve or a blown head gasket. If two adjacent cylinders are misfiring, it's likely the head gasket between them has failed. Also, if an engine is overheating or losing coolant, it's likely the head gasket is the culprit.

Intermittent misfires are the worst kind to diagnose because the misfire comes and goes depending on engine load or operating conditions. They seem to occur for no apparent reason. The engine may only misfire and run rough when cold but then smooth out as it warms up. Or, it may start and idle fine but then misfire or hesitate when it comes under load. Also, it may run fine most of the time but suddenly misfire or cut out for no apparent reason. Intermittent misfires can be a real challenge to diagnose, so let's start with a steady misfire in one cylinder before moving on to intermittent misfires.

Hope this help.

Mar 25, 2010 | 1989 GMC Sierra

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