95 Impreza 2.2l - Misfire

[Tracon]

Hello, name is Erick, new to this whole scene. I have a 1995 Subaru Impreza, 2.2l and it's been an ongoing issue with the Check Engine light. The light will come on sometimes and sometimes it won't. The time it has come on it has been driving on the highway going about 55-65MPH

 

In fact the light went on 1 day prior to me posting this and just today as I posted this, the light was no longer lit. I drove it today and the light just wasn't there. I ran it below 50MPH today and no light came on.

 

Now I took it a day ago to have it tested at an auto store, came back with a P0301 - Cylinder #1 misfire. Now I will assure you my skills in cars are well below anything, however, I learn quickly and read instructions well, so doing something on my own is okay, so I looked over the items that this misfire reads, I checked the Spark Plugs, Wires and all that it says and I figure I have 1 or more of the 3 remaining sources of the misfire.

 

1) Faulty Coil Pack

2) Faulty Oxygen Sensor

3) Faulty Computer

 

 

I haven't had issues turning on the car, nor do I feel the far jumpy. She rides smoothly at 60+MPH and below of course and I just don't have any known issues. I can say honestly the only thing that I wonder and maybe it's because it's the type of car, the 2nd gear kicks in hard sometimes, a jerk rather then a smooth transition. However, I think that has more to do on how I push on the gas.

 

Anyone can help me out a little, I'll try my best to respond to tech questions but like I said, I'm a newbie and trying my hardest to keep up. Thanks anyone

 

 

Erick -

[johnceggleston]

a P0301 - Cylinder #1 misfire. I checked the Spark Plugs, Wires and all that it says and I figure I have 1 or more of the 3 remaining sources of the misfire.

 

1) Faulty Coil Pack

2) Faulty Oxygen Sensor

3) Faulty Computer

 

Erick -

 

 

this is a fairly common question so i will give you a fairly common answer.

 

how long has it been since you changed the plugs and wires? not all mis fires are caused by plugs and wires but are lot, i mean A LOT, of them are.

what kind of plugs and wires did you use? this makes a difference to some cars, yours may be one of them. subaru wires and NKG (NGK?) wires are recommended. you can get the subaru wires on line for a fair price. maybe, probably more than discount wires at the local parts store but not too much money for what you get.

 

try moving the #1 plug wire to the rear of the engine, #3, and see if the misfire follows the wire or if it stays with the #1 cylinder. (#1 is the front cylinder on the passenger side. #2 is front driver side.)

 

other stuff can cause misfires but:

1. the coil pack usually affects 2 cylinders at a time , not just one.

2. the o2 would probably affect more than just one cylinder, depending on mileage and age it may be due but probably not causing your misfire.

3. computers, ECUs, almost never go bad, of course they can but this probably isn't your problem.

 

when was the last time you had a tune up??

how many miles?

how long have you been dealing with this?

how long have you had the car?

does it happen anytime or only when it rains?

 

misfires have to happen twice, i think, to set a CEL. i have pulled plug wires to check other stuff and not set a cel. and they will clear themselves if they have not occurred lately?

 

 

and finally, welcome to the board!!

Edited October 17, 2010 by johnceggleston

[Tracon]

when was the last time you had a tune up??

how many miles?

how long have you been dealing with this?

how long have you had the car?

does it happen anytime or only when it rains?

 

1) The last tune up was in April 2010, all spark plugs were changed and the wires were changed.

2) The car has 94600 miles

3) This is the first time the P0301 misfire code has hit. However, like I said, the light went on yesterday while on the highway going 60+MPH. Today when I went out, the light was no longer lit. (I did notice I forgot to put, while I was driving on the highway I noticed the light blink, but not constant, it was just like turn off and back on. I also noticed some moments while at a red light, I noticed the light was somewhat flickering, like a bad light bulb lit but flickers slightly. That went away and was solid amber)

4) No, it hadn't rained in nearly 80 days prior to a very light sprinkle last night into the morning. El Paso, Texas we've had nothing but 80-90+ degree hit since March, still in the 80's now.

 

 

I hope this helps.

[johnceggleston]

1) The last tune up was in April 2010, all spark plugs were changed and the wires were changed.

2) The car has 94600 miles

3) This is the first time the P0301 misfire code has hit. However, like I said, the light went on yesterday while on the highway going 60+MPH. Today when I went out, the light was no longer lit. (I did notice I forgot to put, while I was driving on the highway I noticed the light blink, but not constant, it was just like turn off and back on. I also noticed some moments while at a red light, I noticed the light was somewhat flickering, like a bad light bulb lit but flickers slightly. That went away and was solid amber)

4) No, it hadn't rained in nearly 80 days prior to a very light sprinkle last night into the morning. El Paso, Texas we've had nothing but 80-90+ degree hit since March, still in the 80's now.

 

 

I hope this helps.

 

i should have caught el paso, asking about rain in elpaso is pretty dumb.

 

move the plug wire to the rear. next time the cel comes on see if it is the same cylinder. a CEL light that is flashing usually means that it is a light you should address immediately, but if you can feel it missing or know you have a problem in that area you probably do not have to drop everything and have the codes read. but if you wait too long to read the codes, it may reset before you know what the code was, and then you are just left wondering.

 

what kind of plugs and wires did you use?

 

move the wire , it's an easy way to help diagnose the problem. (one of the wires is longer than the others, if it happens to be #3 just move the wire to the other side rear cylinder.)

Edited October 17, 2010 by johnceggleston

[Tracon]

Thanks for all the information. I will switch the plugs out next time that light comes on. I must say that I haven't felt anything strange with the car. Shes been smooth, do you happen to know what I should feel or sense in a misfire, something that might not be obvious?

 

btw, I know you asked about the plugs, the current plugs are NGK G-Power - 7092

Edited October 17, 2010 by Tracon

[Ricearu]

a misfire should feel like a little jump while driving. it could easily be confused with a bump in the road to someone who isn't familiar with mechanics.

 

I believe what he was asking was not only plugs, but the wires. The spark plug wires are important. If you bought the auto parts store special, then the CAN be the problem, no guarantees though. swap the wires like he said and see if it changes from #1 to another cylinder. I too recommend NGK wires or OEM subaru. The junk aftermarkets just don't hold up. in fact when I bought my car, it had duracraps on it. they sucked and I had misfires through the wall to ground. I grabbed a set of USED NGK wires from the JUNK YARD for a quick (AND FREE) fix. they lasted another 2 YEARS

[Ricearu]

http://www.rockauto.com $40 for the set plus shipping NGK Part # 8004