Misfire 3 and 4 subaru

After driving the car hard, the check engine light started flashing, so I got home and scanned the code. I got a misfire in cylinders 2 and 3. I have replaced the spark plugs with oem ones, I have also switched the coils from a good cylinder with a bad cylinder, and I have checked the fuel injectors, which I also interchanged, but I continue to have misfires in those cylinders. I'm not sure what to check for next, so I am asking for some advice.

Do you. Was this answer. Ok thanks. Since im kind of newbie to cars, what will a compression test determine? Recheck the coils -cyl 1 and 2 shares the same coil Was this answer. I ordered a compression tester, which will be arriving the next couple of days. I will probably do the compression test this weekend because of work, but I will get back to you with the results as soon as I can.

misfire 3 and 4 subaru

Thanks Was this answer. I did the compression test on cylinder 2 and I got psi and the same for cylinder 4.

I only had time to do those two, but I think they look ok, right? Well I just finished doing the compression test on cylinders 1 and 3 and I got some bad results. Cylinder 3 has no compression at all. In your expert opinion, how much would the repairs be if it was the valves? Or rings? Or would I be better off finding a used engine? My opinion I'll go for a used engine Was this answer. Please login or register to post a reply. Easy step by step guide on how to troubleshoot and repair an automotive engine cylinder misfire P, P, P, P, P, P, P, P and P, though I Have Check Engine Light Started Blinking.

Sponsored links. Ask a Car Question. It's Free!Whenever you remove a Subaru cylinder head you should always look at the valve guides to see if there is any evidence of them moving, particularly the exhaust valve guides. I have seen these guides moves causing misfires or even worse completely drop causing valve to piston interference. The problem seems more prevalent in the 2. Below are some pictures so you can get an idea of what it looks like when the valve guide moves or drops.

The misfire will be detected and the code stored. Well now here in Oregon your car will not pass a DEQ emissions test.

Subaru - Forester :: 2009 - Continues To Skip / Misfire On Cylinder 3 And 4

I have seen this problem as intermittent as once a month to a continuous misfire valve guide dropped holding valve partially open. Check the guides for excessive clearance; if the engine overheated I have seen them shrink also. If the guide to valve clearance is okay then just knock the guide back in place and knurl it. It will never move again if you do it correctly. Just make sure the valves are good and replace the seals.

If you find this information helpful please consider a donation. These articles, questions and comments are very time consuming so even a small donation gives me motivation to keep educating automotive owners.

All proceeds go to the expansion and maintenance mdhmotors. Thank You. I just had a valve spring go. Bent the valve. Codes p and p Will what you posted fix the problem. Car is stuck in Redding right now. Please email us directly if you need to schedule an appointment as comments are delayed response time.

Had the clutch replace recently and the mechanic said there was no oil on the motor. It gets about 32 mpg and still has good power with some vibration around rpm in 2 and 3rd gear consistently but not bad.We don't think so.

Premature brake wear has been a consistent problem for this Accord generation. Once again Honda settled a class action lawsuit over brake wearbut most Accords are NOT covered. Owners have consistently reported uncomfortable seats with the entire 8th generation of Honda Accords. Unwary buyers report the seat pain is mainly only noticeable after minutes. The common theme we hear is "never noticed this during the test drive.

I called Honda because there's a misfire recall. Honda said he couldn't do nothing about it because my car is salvage. This again has been a repeated issue without any help from Honda. The car is only 6 yrs old. Would not run until I replaced the plugs. Honda would not have it towed to the dealership. Also it had a hard DTC code in it that that dealership erased and said wasn't in there. Which is covered under the extended warranty.

misfire 3 and 4 subaru

P misfire cylinder 3. The dealership would not hook the code reader up to it while I was there. Bob boyte Honda in Brandon ms. June trip to St. Petersburg, FL engine misfired, cause bad ignition coil and plug. What happen to the so call best made car in the world.

I purchased this Honda Accord EX in It had 23, plus miles on it. It was previously owned so I was told by someone that could not make the payments. Init started skipping, would not accelerate on a long distance trip. I took it into Honda where it was purchased. I was told there was a Honda Engine recall. One spark plug was replaced I was told a rep was not available, but as soon as one was designated, I would be notified.

It took over a year. The mpg began to decrease from 34 to as little as 15 mpg. When the Honda rep looked at it, Candy, she explained that the oil could leak into the engine from the spark plugs as they were misaligned. I was told it had an extended warranty, 8 years. Well if this is true, what happens after ? At that time, after giving Honda a log I had kept of the mpg, I was told to come back if it continued and they would give a test drive.

Why didn't they do it at this time? Now, 3 days ago, I went to start my car, it stalled, choked, all lights on dashboard came on. It was not the battery, bc it would turn over. I tried 3 times, kept choking offI have a Subaru Impreza that misfires. It can happen at most any speed, not sure at RPMs above I can always make it happen if I turn the air conditioner off and then back on. I have replaced the plugs, wires, front oxygen sensor and ignition coil.

I also ran a can of injector cleaner through it. The check engine light sometimes comes on, and the code was for misfire on 3. What did your 3 spark plug look like when you pulled it out? Compare to the others.

You can try swapping your 3 fuel injector with another to see if the misfire moves with the injector. Hope that the fuel injector is just dirty or plugged. Do like cigroller suggests and swap injectors or just take out 3 and look at the spray pattern. Or just replace it. The plug on three looked good yesterday. I took the car in for a tune up a few months ago.

The only thing they did was change the plugs for dollars. Stilll had the occasional misfire. No check engine light until last week. When I took out the plug in three last night it looked clean, light gray ash, and good gap. Any time a performance problem exists a compression should always be run as a first step.

A cyl. If the compression is down the most likely cause would be tight valve lash; which should be inspected about every 30k miles and is seldom ever done. Inspecting compression should be done no matter the age of the car or the mileage. In a perfect world a late model and even low miles car should not have a compression problem. In the real world problems do occur so weed this potential problem out in advance.

Both cylinder heads were totally trashed to the point where they were not even repairable. Were there any other codes? Checking the compression would not be a bad idea. Goldwing July 5,pm 3. The fuel injector will be a lot cheaper than a compression problem. I have since changed the other items listed, oxygen sensor, wires, and coil pack.

How hard is it to replace an injector??P is a relatively common trouble code with any vehicle, that includes the Subaru Legacy. P is certainly a cause for concern, and should be considered a threat to the drivability your Legacy. It will often be accompanied by codes P, PPetc…. Fixing P should be considered a high priority.

The engine is also not firing all of the fuel, so raw fuel is also passing through Cylinder 4 into the exhaust. Mileage may suffer as well when your Legacy has P as well. P is a cylinder specific misfire code, which means that Cylinder 4 is misfiring and causing the code.

There are quite a few things that can cause the P trouble code to trigger the Subaru Legacy. Here are the most common problems that will throw the code. They are presented somewhat in order from most to least likely to be causing the code:. If you follow the items listed above you should be able to fix the P Inspect and test the parts of the ignition system around the cylinder to determine whether or not you need to replace the coil packs, plugs, or wires.

Intermittent Cylinder Misfire Subaru Valve Guide Problem

Most of the time one of those three things will end up being the problem. You need to reset the trouble codes and swap the coil pack, wire, and plug from Cylinder 4 to another. After that, Go ahead and replace them or have them tested. After that you would want to test the fuel injection system. P is cause for concern and left unfixed can leave you stranded or make the vehicle virtually un-drivable. Fixing the problem causing the code to fire can save you time and money and keep your Subaru Legacy from breaking down.

Quick action may also save your catalytic converter from going bad. Good luck diagnosing the issue. If there is anything that you would like to add please leave a comment below. Subaru Legacy P Definition P is a cylinder specific misfire code, which means that Cylinder 4 is misfiring and causing the code.

2002 Subaru Impreza engine misfire

The vehicle itself may begin to run rough. It depends on how serious the misfire is.

Diagnose P0301, P0302, P0303, P0304 Check Engine Light on a 2005 Subaru Legacy GT

The vehicle may produce excess vibration, especially at lower RPM. Fuel mileage may suffer. You may smell raw gas coming from the tail pipe. The vehicle may backfire. Take a look at the electrodes and see if they are in good shape.

Most vehicles now come with iridium plugs that need changed very infrequently.My 09 Forester continues to skip although I have changed spark plugs and wires.

Always reads misfire on 03 and My Subaru Forester just passed Rhode Island inspection last week. I didn't use for 6 days. Last night when we got home I moved the car and noticed a strong gas smell. This morning on I drove it cold on way to work right away I noticed lack of power at low gear its automatic transa jumpy idle, and some smoke out back not too much and looked whitish.

Check engine light flashed a couple of times but didn't stay on nor flashed continuously. I'm thinking some sort of cylinder misfire. I just bought a 97 Dakota Slt, V6 automatic transmission. It had an intermittent. Skip, diagnostic showed a misfire on 5, changed plugs, cap, rotor,wires. Still has skip when cold and under a load. All cylinders seem to be firing. Thinking it could be injectors? I have Subaru Forester that is idling roughly. Per diagnostic codes I learned that the 2nd cylinder was misfiring.

I replaced the coil, spark plugs, ignition wires, and an airflow sensor. Yet, my car still idles rough. The check engine light is solid and the cruise control is flashing.

The idling problem only happens when stopped… after I get high rpms there is no shaking. I had someone disconnect the battery and reset the computer and the lights stayed off for about a week and idling was fine. Week later — the problem returned. I think this an electrical problem, but not sure if mechanical.

They tell me it needs a valve job for 2, They already put a mass air flow sensor in, and replaced plugs and wires. Still got the miss, but I need the vehicle. Our beloved Subaru Forester has the check engine light on. We've been told that the 4th cylinder has either low or no compression.To advertisecontact our sales department by calling or email sales latc. To offer submissions to editorialcontact editor Bruce Barton at bruceb latc.

Two months ago I wrote an article about a Subaru Outback. The car had been hesitating on acceleration as if it were being hit or pushed from behind while driving. There was a group of Bank 1 misfire codes, and it turned out that the problem was caused by the No. When the speed sensor malfunctioned, it caused a violent upshift, which in turn prompted the car to hesitate, or feel like it was being pushed from behind.

As I stated in my March article, we could not find any obvious problems in the engine, so we felt that the misfires were a byproduct of the violent upshift. The customer called me two weeks ago to report that the check engine light was on again, but the car did not experience any of the original symptoms. When he brought his car to the shop, the first thing I did was check the mileage. The car had traveled 1, miles without a problem. Much to my delight, the P code was not in the system, but all of the Bank 1 misfires were P, P and P This was good news, as we had not yet addressed the misfires.

When originally discovered in March, the curious thing about the misfires was that they were all in Bank 1. All six-cylinder Subaru 3.

Bank 1 has the No. If the computer finds the problem in both banks, we can deduce that it is a systemwide problem, but if the problem is only in one bank, we start to isolate the problem faster. Because it is extremely difficult to perform a compression check on a Subaru 3. We performed a smoke test on the intake to ensure that there were no vacuum leaks. We checked all connections to the coils, injectors and main engine harness.

misfire 3 and 4 subaru

We checked timing and fuel trims. All were OK. We then knew we had to perform the compression test. Four hours later we found that cylinders Nos. Spec is psi, with a low limit of psi. What could affect one head and not the other?

Subaru Legacy P0304: Cylinder 4 | Misfire Detected

If the timing chain were jumped one tooth, it could cause the problem, but if it were jumped, the problem would be there all the time. So it was not jumped. The engine has a variable valve timing system. Back in the days when cars had distributors, engine timing could be manipulated by a vacuum advance.


Comments

Leave a Reply

Your email address will not be published. Required fields are marked *