Subaru Outback Forums banner

1 - 9 of 9 Posts

·
Registered
Joined
·
4 Posts
Discussion Starter #1
i have a 98 subaru legacy outback i put new plugs and wires on it when it is at a idle it runs rough and then the check engine light comes on code is always cylinder 4 misfire it runs fine other wise any ideas
thanks
Ron
 

·
Registered
Onyx, 2008 LL Bean 3.0R and 2017 Honda Civic Hatchback Sport Touring
Joined
·
4,112 Posts
If it started running rough AFTER you put the new plugs and wires in, I would take a multimeter and check the continuity of the wires, make sure the spark plug in cyl 4 is seated properly, and check the coil. There are threads you can search here for the procedure to check the coil.

If you put the plugs and wires in to try and fix the running rough (seems more likely), than I defer to one of the more experienced gurus here.
 

·
Registered
Joined
·
4 Posts
What you can do too is, get a spray bottle full of water and with the car running mist the plug wires and look to see if any of them are arching out.

It is possible to receive a bad plug wire even if it's new. It's happened to me before. Hope this helps you out.

Tony
 

·
Registered
Joined
·
4 Posts
Discussion Starter #4
i am going to try a nother new plug on that cylinder it was doing it when i got it a few weeks back when driving it it runs fine was wondering if a fuel injector could be clogged and not allowing enough fuel when at a idle
 

·
Registered
03 H6 OBW & 06 WRX Sportwagon
Joined
·
17,553 Posts
I was gonna ask why you did the plugs and wires.

also, what brand of plugs and wires?

Any chance you had a little trouble on cyl 4 and maybe banged the electrode closed?


run a can of seafoam or Techron through a tank of gas.

miles on car? condition/maintenance? recently purchased?
 

·
Registered
Joined
·
4 Posts
Discussion Starter #6
the first thing i did was run seafoam in it the plugs are denso plat and the wires are autolite the problem was there when i got the car it has 160,000 on it i checked the plug before i put it in the electrode was not bent i used a spark tester and coil and wire at plug end are firing a good blue spark
i used a spray bottle at nite there were no arcs on any thing
 

·
Registered
03 H6 OBW & 06 WRX Sportwagon
Joined
·
17,553 Posts
^^^^^ +1 on compression test. And swapping injectors with another cyl would confirm/negate the injector theory.

recently, a guy on a Forum discovered his dead cyl 4 had only 25 psi compression.

some folks have problems with plug wires other than OEM. I have no idea about success with Autolite. If you still have the old plug wires, you could try substituing one in on cyl 4 as a test I suppose.
 
1 - 9 of 9 Posts
Top