[Arickrose]

I just had all the spark plugs replaced in my 2003 Outback and the check engine light is still on and it is still running very rough. Any suggestions?

 

[CNY_Dave]

What are the codes? Autozone etc can read for free.
if not a 6 cylinder- How old are the wires? If you have an ohmmeter you can test them.

 

[z28dug]

Agree with CNY_DAVE. What are the codes? What made you think it was the spark plugs?

 

[traildogck]

3 of us waiting on the same....

 

[AWDFTW]

No info given, no help possible.

Miles on vehicle?
H4 or H6 engine?
What codes are being displayed?
Known service history?
Known mechanical issues?

...ANYTHING?

 

[mjohnson]

.....

...ANYTHING?

It seems to run rough! :grin2:

 

[mjohnson]

I just had all the spark plugs replaced in my 2003 Outback and the check engine light is still on and it is still running very rough. Any suggestions?

Codes.....

Could be blocked air filter. Blocked IAC, a very dirty manifold, maybe PVC valve..... Timing belt could have skipped a tooth or two.

Service history?

 

[Arickrose]

Sorry to take so long to reply - had major computer problems at work.

The car has about 105K miles
H6 .engine
Early in the summer I needed a new alternator (and battery), which worked for about 2 months and then stopped charging. The mech. said it tested good but I made him replace the alternator and it has been charging fine. Then the car started this rough running so the mechanic used his OBD and said 5 of 6 cylinders read bad so he replaced all of them. (I didn't see the codes).
I've had the car about 5 years with no mechanical problems and now engine problems. Have only done regular maintenance.
Does this help at all?

 

[eagleeye]

Sorry to take so long to reply - had major computer problems at work.

The car has about 105K miles
H6 .engine
Early in the summer I needed a new alternator (and battery), which worked for about 2 months and then stopped charging. The mech. said it tested good but I made him replace the alternator and it has been charging fine. Then the car started this rough running so the mechanic used his OBD and said 5 of 6 cylinders read bad so he replaced all of them. (I didn't see the codes).
I've had the car about 5 years with no mechanical problems and now engine problems. Have only done regular maintenance.
Does this help at all?

ez30D are very particular about what alternator goes on it. parts stores do not sell anything useful, except useful at giving repeat problems.



subaru dealers want a whole lot for the right mitsubishi USA (new or reman).

this is a new one,...(not a half fixed turd form the parts store). ...I think i would take one from a junk yard if I could see it came out of a EZ30D car, with 3 wires and a mitsubishi USA mark.

$125?, free shipping, and no core charge. (I bought one for my H4 car, ...had it in 2 days, shipped from a warehouse closer then TN)

https://www.dbelectrical.com/products/subaru-outback-3-0l-alternator-01-02-03-04-05.html

other things:

engine grounds.

 

[fisherella]

This is totally an unsubstantiated guess, but maybe coil pack?

H6 + rough running = coil pack has been my experience.
The CEL codes could help narrow it down.

 

[eagleeye]

This is totally an unsubstantiated guess, but maybe coil pack?

H6 + rough running = coil pack has been my experience.
The CEL codes could help narrow it down.

as opposed to a central coil, smarter coil on plugs on these,

and the only complaint, is occasionally the locking mechanism does not latch down hard enough on old ones, and people lock em down with a bread tie type wire or zip tie....but keep on using them.