Question about 2004 Subaru Forester

1 Answer

Cylinder 4 misfire plugs coil and wires okay about 20% compression rate

Posted by on

Ad

1 Answer

  • Level 1:

    An expert who has achieved level 1.

  • Contributor
  • 1 Answer

You need to change your 4th plug wire as there is a break in it

Posted on Aug 25, 2011

Ad

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
Best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of.(from cars to computers, handyman, and even drones)
click here to download the app (for users in the US for now) and get all the help you need.
Goodluck!

Posted on Jan 02, 2017

Ad

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

Why is there a cylinder 2 misfire?


Check these three things in the misfiring cylinder: spark, gas, and compression. One of them is wrong or missing. For spark check the spark plug and wire. Make sure you have spark on the plug wire, a strong blue spark. For gas, the fuel/air mixture may be wrong. Does the fuel injector pulse, putting gas into the cylinder? Possibly you may have a leaking injector or a clogged injector.

If gas and spark seem okay, you need to check compression in the cylinder. Low compression will cause a misfire. If compression is 20 or 25% lower than adjacent cylinders, that could be causing a misfire. For example, say numbers 1 and 3 cylinders had about 150 psi compression. 80% of 150 = 120, so if cylinder 2 is 120psi or less, that could be setting the misfire code. Low compression can be caused by valves not seating well, or bad piston rings, bad head gasket- something in the combustion area of the cylinder is losing compression.

Aug 17, 2015 | 2006 Mazda Tribute

1 Answer

Misfire on Cylinder 3 swapped plugs between 3 and 4 on Pontiak Aztek 2003. Misfire remained on cylinder 3. Swapped ignition coil 3 and 6 with ignition coil 1 and 4 misfire still on cylinder 3


Try a new plug wire on cyl 3 if that doesn't fix it you could have a bad valve or compression problem on cyl 3 Try doing a compression test also If it has injectors for each cylinder you could have a bad injector for cylinder number 3

Dec 04, 2014 | 2001 Pontiac Aztek

1 Answer

Misfiring on cylinder #3


Misfiring can be cause by ignition coil,spark plugs,wires,engine valve,cylinder compression,
if it's a quad four then crack around the ignition coil. there is 2 coils like 1-4 coil and 2-3 coil
first check spark plug color or foul of gaz
hope it help

Oct 18, 2014 | 2002 Pontiac Grand Am SE

1 Answer

WHEN I GIVE IT GAS IT START TO MISFIRE


Misfires are caused by one of 3 things-gas, spark, or compression-one of those is the problem. For gas, check the fuel pressure and see if it is at the right pressure for your car. Low fuel pressure will cause misfires. If pressure is good, it could still be an injector problem, like a clogged injector. If low pressure, suspect the fuel pump or the fuel filter.
For an ignition spark problem, check your spark plugs. Pull them out and inspect them for broken or cracked plugs, check the spark plug gap, check for oil fouled plugs. You may be able to isolate the misfire to a cylinder or two by the plugs condition. A misfiring plug or cylinder should show more black, sooty deposits than the other plugs. A normal firing plug will have a tan or brown colored insulator on the end with very little deposits. If the plugs are okay, clean them a bit if needed, and check for spark on the spark plug wire ends with engine cranking. Buy an inexpensive spark tester, or hold each spark plug wire metal end terminal 1/4 inch from a ground on the engine block, while cranking the engine. Wear a heavy glove to avoid getting shocked. Check that every cylinder is getting a strong blue spark to eliminate ignition as a problem. A weak, yellow or orange spark is an ignition problem, possibly a bad coil, or other ignition part.

If spark and gas is good, you may need to check engine compression. Any cylinder that has significantly lower compression than the other cylinders will cause a misfire, and set a misfire code. You should check for any trouble codes in the engine computer. A code reader or scanner would have to be connected to the diagnostic connector under the dash. What is "significantly lower" compression? About 15-20% less compression. Say you checked and had 150 psi compression in most cylinders. If one had 20% lower compression ( 150 X 20%= 30 psi, 150 -30 =120 psi, or same as saying 150 X 80%= 120 psi.), a condition like that can cause a misfire. I hope I have made sense here. Good luck, and post back what you find, or if any questions.

Apr 10, 2014 | 1998 Ford Windstar

1 Answer

Miss fire


Hi Richard, I'm glad to help! Richard, there's a lot of things that can cause one certain cylinder to misfire. I would first: "Replace the Spark Plug and Spark Plug Wire for number 4 and see if the misfire goes away. If it doesn't then you need to do a "Compression Test" for cylinder # 4 and compare it to another cylinder and if its more then 25 Psi difference then you need to do a "Cylinder Leak Down Test" to see where you are loosing the compression. If the compression is good and you have new plug and wire and it still misfires. Then you'll need to check and make sure you have good spark coming from the coil. If you have good spark coming from the coil. Then you'll need to check and make sure the # 4 Injector is firing. Hope this helps and have an awesome day Richard.

Apr 07, 2014 | 2000 Dodge Grand Caravan

1 Answer

1999 mercury mystique cylinder 2 misfire ! Changed gasket, plugs, wires, and coil pack and problem still exist !!! Please help !!!


Okay kevin, the first thing is to make sure there is no vacuum leak, start the car and look and listen around for a hissing sound.if no leak is found then we will move on to the next test which would be a compression test, this test will tell you if the cylinder has compression and will help with the next step. seeing that you replaced the plugs wires and coil pack, if you have good compression then the injector would be the next step. check the connector on injector, if all looks good then the next step would be to swap injectors from that # 2 cylinder with #4 and then drive the car and if light comes back have it scanned and see if the misfire moved to cylinder #4. if it did move then you will be sure it is the injector. do compression test first , test all cylinders, make sure to have all plugs out and unplug coil pack connector when doing compression test. write me back with the results. good day

Nov 12, 2012 | Cars & Trucks

1 Answer

How do i fix a misfire on a 1996 suburban


Hi Yvonne, I'm glad to help!

The first step when you have a misfire is to see what is causing the misfire. Technicians always rules out mechanical failures before moving on too Electrical issues. What you need to do is check compression on cylinder 2 and see if its good. Remove the spark plug and test it with a compression tester. It should read somewhere around 150 PSI or more. Check it to cylinder 4 and make sure the reading are close they must be within 25 %. If the compression is GOOD then you'll need to move to the electrical checks. Here's how you rule out parts. It doesn't matter if you have plug wires or coil-on-plug. SWAP the parts from cylinder 2 to cylinder 4 and start the engine and if the misfire moves from 2 to 4 then you know its either the spark plug the spark plug wire or the coil pack if you have a coil instead of a plug wire. If the misfire does not move and stays in cylinder 2 then it could be an INJECTOR, WIRING ISSUES, COMPUTER DRIVER. As you see Yvonne it can be a lot of things that can cause a misfire. Hope this helps and have an awesome day Yvonne.

Apr 11, 2012 | 1996 Chevrolet Tahoe

2 Answers

99 cougar v6 P0352 misfire cylinder 3 and 4 replaced igntn coil..


Had the same problem, car was misfiring on cylinder 3 and 4. replaced wires, plugs, and ignition coil. still misfired on the same cynlinders. turned out the main engine wiring harness plug in was coming loose. spent well over $150 on the unneccesary repairs and ultimately fixed the problem wit a $3 bag of wire ties to hold the plug in...

May 04, 2009 | 1999 Mercury Cougar

Not finding what you are looking for?
2004 Subaru Forester Logo

Related Topics:

117 people viewed this question

Ask a Question

Usually answered in minutes!

Top Subaru Experts

yadayada
yadayada

Level 3 Expert

76649 Answers

Colin Stickland
Colin Stickland

Level 3 Expert

22219 Answers

Jeff Turcotte
Jeff Turcotte

Level 3 Expert

8522 Answers

Are you a Subaru Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...