Subaru Outback Forums banner

21 - 40 of 50 Posts

·
Registered
Joined
·
257 Posts
Passing the inspection is indeed important. But ignoring the problem will cost you greatly if you continue to ignore it. Misfires can lead to burned valves and damaged catalytic converters. Next you'll be telling us about the P0420 codes you've logged!

If you can't solve this yourself, seek out a trusted mechanic.
Yes, you need to fix the problem. My suggestion is not to clear the codes after you fix the problem so you don't have to run all of the readiness tests meet the emissions requirements.

As a professional mechanic with a 100% success rate on resolving P0300 codes, I appears to me that you have outstanding advice on how to fix the problem in the thread above.
 

·
On the Super Mod Squad
2002 Pair: 3.0 VDC Wag & 2.5 Limited Sedan
Joined
·
25,337 Posts
Yes, you need to fix the problem. My suggestion is not to clear the codes after you fix the problem so you don't have to run all of the readiness tests meet the emissions requirements.

As a professional mechanic with a 100% success rate on resolving P0300 codes, I appears to me that you have outstanding advice on how to fix the problem in the thread above.
sucks when you have to disconnect a battery to do work on a car, just before it is due for a annual inspection.

and I am sure that the directions on how to make a typical drive cycle were worked out in places like the GM proving grounds at Yuma and Mesa Arizona, where they can drive around in a circle without traffic or stop signs,....and they found out they should not attempt to start the cycle when the ambient air temp is ove 122 degrees F.

 

·
Registered
2013 Subaru Outback Ltd
Joined
·
217 Posts
Discussion Starter #23
Passing the inspection is indeed important. But ignoring the problem will cost you greatly if you continue to ignore it. Misfires can lead to burned valves and damaged catalytic converters. Next you'll be telling us about the P0420 codes you've logged!

If you can't solve this yourself, seek out a trusted mechanic.
I would definitely have tried to repair. However it's been very cold to work on the car outside (I don't have garage), and it's been very very busy time for me, I just can't find time engaging myself into repairs now. My only concern is to pass the inspection and I will take care of the misfire when things slow down a bit in my life.

My idea now is.....I have OBD II USB cable that I can connect to my laptop with few softwares to run diagnostics....After I reset CEL I hope the software will show me readiness state, and may be I can go for inspection as soon as it is ready with a hope that CEL not going to light up at the inspection station. :)
 

·
Registered
Joined
·
22,836 Posts
The inspection process can tell if any codes were cleared within the last 100miles or so. I replaced a bad fuel cap a few days before my inspection. Even with the code clearing out on its own they could tell I had cleared a code earlier and told me to come back in 100miles. Had I left the code and it cleared via the system I probably would have been OK
 

·
Registered
2013 Subaru Outback Ltd
Joined
·
217 Posts
Discussion Starter #25
Ok I just had an idea....and it might be not a good idea, so correct me if I am wrong. What if I swap spark plug wires? For example I remove suspected bad wire from cylinder 2 and ignition coil and swap it with cylinder 4 wire for example. And then will check if misfire transfers to cylinder 4. If it does not transfer to cylinder 4, this would mean wire is OK and next would be suspecting ignition coil. Is it bad idea?
 

·
On the Super Mod Squad
2002 Pair: 3.0 VDC Wag & 2.5 Limited Sedan
Joined
·
25,337 Posts
typically on threads like this it is recommended to swap plug wires around to see if you can get the misfire to move. and then swap plugs around to see if you can get it to move. (using some anti-sieze on the threads of the plug to make sure none get stuck from the repeat action on them).
 

·
Registered
2013 Subaru Outback Ltd
Joined
·
217 Posts
Discussion Starter #27
typically on threads like this it is recommended to swap plug wires around to see if you can get the misfire to move. and then swap plugs around to see if you can get it to move. (using some anti-sieze on the threads of the plug to make sure none get stuck from the repeat action on them).
I already swapped suspected bad plug with new one, so it's not bad plug. Now I just want to swap wires.
 

·
Registered
Joined
·
257 Posts
Let me try this again....
You do not want to "reset the CEL". That removes all if the redness data and all if the rediness tests will need to be completed before it is emissions ready.

If you repair the misfire and do not "reset the CEL", the light will go out after the misfire test has run and it will be emissions ready without having to run all of the other rediness tests.
 

·
Registered
2008 Outback 2.5i, 2009 Forrester 2.5 sohc
Joined
·
603 Posts
Maybe its overkill, but I would replace all four plugs with NGK , the wireset with NGK from RockAuto, and an OEM ignition module from a dealer.
 

·
Registered
2013 Subaru Outback Ltd
Joined
·
217 Posts
Discussion Starter #30
Here's an update: I haven't tried to swap wires yet but the CEL went off 3 days ago without resetting the code. However when I connect scanner now, it tells me "Stored code P0302". What does "Stored" mean? Does it mean it's active without CEL, or it sees it as old code which is not active?
 

·
On the Super Mod Squad
2002 Pair: 3.0 VDC Wag & 2.5 Limited Sedan
Joined
·
25,337 Posts
Here's an update: I haven't tried to swap wires yet but the CEL went off 3 days ago without resetting the code. However when I connect scanner now, it tells me "Stored code P0302". What does "Stored" mean? Does it mean it's active without CEL, or it sees it as old code which is not active?
stored = old code not active.
 

·
Registered
2008 Outback 2.5i, 2009 Forrester 2.5 sohc
Joined
·
603 Posts
Here's an update: I haven't tried to swap wires yet but the CEL went off 3 days ago without resetting the code. However when I connect scanner now, it tells me "Stored code P0302". What does "Stored" mean? Does it mean it's active without CEL, or it sees it as old code which is not active?
When was the last time you replaced the plugs and wire set? For 100, you can get plugs, wires, and a Beck Arnley ignition module from RockAuto, then you will know you have a baseline of good parts. A misfire could also be a leak in the intake manifold gasket, try spraying brake cleaner around the intake on each side of the engine while running, see if you notice a change in idle.
 

·
Registered
Joined
·
257 Posts
Here's an update: I haven't tried to swap wires yet but the CEL went off 3 days ago without resetting the code. However when I connect scanner now, it tells me "Stored code P0302". What does "Stored" mean? Does it mean it's active without CEL, or it sees it as old code which is not active?
It means the misfire is no longer occuring. Stored codes won't prevent you from passing emissions. Only active codes are disqualifying for emmissions testing.

Provided the codes haven't been recently cleared or the battery disconnected, the other rediness tests should be completed and it should pass.
 

·
Registered
2013 Subaru Outback Ltd
Joined
·
217 Posts
Discussion Starter #34
This is more confusing now. CEL came back, but the scanner still shows "Stored".
I have also swapped the wires with cylinder 4, but the code did not change, it's still P0302. Next....ignition coil?
 

·
On the Super Mod Squad
2002 Pair: 3.0 VDC Wag & 2.5 Limited Sedan
Joined
·
25,337 Posts

·
Registered
2013 Subaru Outback Ltd
Joined
·
217 Posts
Discussion Starter #37
Replaced coil pack. I believe I completed drive cycle since I drove quite a lot after replacement. CEL is still on, I did not reset it after replacing the coil pack. I am driving on expired inspection.
So in order to sum up this is what I did so far:
replaced spark plug
swapped wires
replaced coil pack
still same error P0302

Is there anything else simple I can try before taking it to a shop for diagnostics?
 

·
Registered
2013 Subaru Outback Ltd
Joined
·
217 Posts
Discussion Starter #38
I just remembered that I had replaced fuel filter not long time ago with some cheap filter from ebay. Could this cause misfire? Any way to test before buying new filter?
 

·
On the Super Mod Squad
2002 Pair: 3.0 VDC Wag & 2.5 Limited Sedan
Joined
·
25,337 Posts
I just remembered that I had replaced fuel filter not long time ago with some cheap filter from ebay. Could this cause misfire? Any way to test before buying new filter?

nope, then you would have all 4 misfires. unlike other makes they say here not a lot gets in that one anyway as the pump has a filter / screen on it that keeps most of the stuff in the tank.
 

·
On the Super Mod Squad
2002 Pair: 3.0 VDC Wag & 2.5 Limited Sedan
Joined
·
25,337 Posts
Replaced coil pack. I believe I completed drive cycle since I drove quite a lot after replacement. CEL is still on, I did not reset it after replacing the coil pack. I am driving on expired inspection.
So in order to sum up this is what I did so far:
replaced spark plug
swapped wires
replaced coil pack
still same error P0302

Is there anything else simple I can try before taking it to a shop for diagnostics?

is it a active misfire with a flashing check engine light?

or a stored one.
 
21 - 40 of 50 Posts
Top