I've been hearing couple of people having problems

i have a set

should i remove it?

It seems fine at this point?

I put some in my wife's Legacy a while back and never had any problems. Been in there around 30K now. If they seem fine I say leave them alone. I use the NGK copper in my RS but I change them every year

i've had mine in for about 10k and no probs yet.
edit: ... what kinda problems??

If you get the CORRECT heat range plugs for you engine there is no problem.
**The parts counter application book might be wrong, so double check first!

There are no known problems with any BOSCH product in a Subaru.

Well glad to hear most people didn't have problem..

I've had those plugs myself. I noticed the Idle is better with the NGK plugs. I have Idle issues anyways with the TEC-II, and the bosch were not helping.

As the grease monkeys once said, Don't mix Japanese with European and Vice Versa.

hehehe...Thats funny considering that ngk's are made in North Carolina

I'm one of those people with a problem with bosch 4's. they burnt my coil up. I don't know why. all I know is I put them in, left the drive and got CEL. pulled the plugs, put chaps in, took it to the shop and had the coil replaced.

So was it plugs that caused problem or installation?

i've been using the bosh +4's in my 98rs and they workgreat. i just got my car back from the dealership and they put the stock plugs in and i noticed it as soon as i left the lot. the bosh plugs rev better and idle better .

I put the bosh Platinum +2’s in my subaru forester. Not good.
The parts guy recommended the +2’s over the +4’s because he had a note on his computer that the +4’s would foul in the 2.5L motor. He recommended the Bosh over the NGK
My old plugs were NGK(I found out after I bought the bosh)
My subaru now idols like a Harley… It’s fine when it revs up, and my gas mileage is the same.. as for the money back guarantee…. Not much of a guarantee.. do you know how hard it is to change plugs in a subaru.. Great I get my $20 bucks back for the plugs and now I’ve spent well in excess of $100 in labor doing the job twice!!

Subaru told me they only use NGK plugs. Funny thing the subaru mechanic said “don’t use German anything on a Subaru”
:mad:

....

My last tuneup, less than 6k ago, i put in a set of +4's on my 02 outback sport. Since then i kep getting a lot of check engine lights that read knock sensor error, but engine runs fine save for really rough idle below 1k rpm, time to pull them or something more sinister?