axel Posted May 15, 2009 Share Posted May 15, 2009 (edited) My 2000 Legacy's Plugs now have 30k miles on them, There are no performance issues yet. Engine runs just fine. How many miles beyond 30k can I anticipate the plugs(NGK copper) going without showing performance issues. When changing the plugs, what problem areas should I be prepared for? What socket extensions will I need to access the plugs and make plug changing easiest? Are the NGK G-Power Platinum Alloy Plugs (BKR6EGP) Good plugs to use? They're resistor plugs, right? Edited May 16, 2009 by axel Link to comment Share on other sites More sharing options...
Rooster2 Posted May 16, 2009 Share Posted May 16, 2009 Plugs can last a long long time. I bought my 99 OBW with 148K miles on the odo. The car ran pretty good, but I decided to change the plugs and spark plug wires, just so I would know that the plugs and wires were new. I quickly figured out that the plugs and wires were all original. I was surprised that spark plugs would drive 148K miles. To replace the plugs, you will need 3/8 inch drive swivel, appx. inch and a half extension, appx 3 inch extension, and a 6 inch extension, and 5/8" plug socket with rubber insert. Remove the air intake duct work on passenger side, remove battery and washer fluid reservoir to gain access. I have heard others say that they have loosened motor mounts, then jacked up the motor a side at a time to help gain access. The big problem is getting access to the plugs. There is just so little room to work with the inside fender well in the way. It took me about 3 hours over two nights to replace my plugs. I replaced only two a night to keep from getting overly frustrated. Just take your time, and cuss a lot like I did, and you will be successful. If the spark plugs have been in the car for a long time, the rubber boots on the spark plugs like to bake themselves on really tight. If they are really hell to remove, then the wires are prolly old, and need to be replaced as well. Use a lot of antisieze on the new plug threads. Antisieze helps lube the threads of the new plugs, assisting easier hand threading upon installation, and removal when you put in a new set of plugs many miles later. Good luck with your work! Link to comment Share on other sites More sharing options...
nipper Posted May 16, 2009 Share Posted May 16, 2009 I would suggest untill you have a running issue or 100,000 miles whichever comes first (no cel no ping). Change the fuel filter, air filter and PCV valve regularly and you can get more then 30K out of the plugs. When you do change the plugs if you decide to go with the upper end, change the wires at the same time. nipper Link to comment Share on other sites More sharing options...
axel Posted May 16, 2009 Author Share Posted May 16, 2009 Thanks for the info, guys. I think that I'll wait for signs of deteriorating engine performance before dealing with the plug change. Then, maybe have someone who's experienced in doing plug changes on a Subaru 2.5L engine do it. Poor clearance between fender and heads making for difficult plug access? Possibly loosening motor mounts and raising side of engine just to change spark plugs? Screw that!!! On most cars, plug changes are pretty simple and straightforward but changing plugs on a Sube 2.5L seems like an extremely unfriendly do-it-yourself Subaru owner process:mad:. Sounds like changing plugs on a Sube's 2.5L engine is good for a vicious migraine headache:eek:....I've had my share of those and don't need any more of them. Link to comment Share on other sites More sharing options...
ron917 Posted May 16, 2009 Share Posted May 16, 2009 Remove the air intake duct work on passenger side, remove battery and washer fluid reservoir to gain access. I have heard others say that they have loosened motor mounts, then jacked up the motor a side at a time to help gain access. The big problem is getting access to the plugs. There is just so little room to work with the inside fender well in the way. It took me about 3 hours over two nights to replace my plugs. I replaced only two a night to keep from getting overly frustrated. Just take your time, and cuss a lot like I did, and you will be successful. Is it that hard on the SOHC engines? Axel has a 2000 which would have the SOHC. What you describe is accurate for the DOHC, but the SOHC looks much easier. Oh, well, guess I'll find out soon enough when I change the plugs on my '07. Axel, not all cars have easy access to spark plugs. Look at a transverse mounted V6, for example. I haven't done it yet, but in my minivan, changing the back 3 plugs requires removing two motor mounts and rotating the engine/transaxle forward while not breaking anything. Link to comment Share on other sites More sharing options...
nipper Posted May 16, 2009 Share Posted May 16, 2009 There are cars out there that are even tougher to change plugs on. SUbarus are just "difficult" but not to bad with the right amount of swearing, and human sacrifice to the mechanical Gods. nipper Link to comment Share on other sites More sharing options...
Gloyale Posted May 16, 2009 Share Posted May 16, 2009 SOHC subaru engines are easy to change plugs on. WAY easier than on a V6 Dodge Caravan or Honda Accord. Link to comment Share on other sites More sharing options...
StructEngineer Posted May 16, 2009 Share Posted May 16, 2009 Thanks for the info, guys. I think that I'll wait for signs of deteriorating engine performance before dealing with the plug change.Then, maybe have someone who's experienced in doing plug changes on a Subaru 2.5L engine do it. Poor clearance between fender and heads making for difficult plug access? Possibly loosening motor mounts and raising side of engine just to change spark plugs? Screw that!!! On most cars, plug changes are pretty simple and straightforward but changing plugs on a Sube 2.5L seems like an extremely unfriendly do-it-yourself Subaru owner process:mad:. Sounds like changing plugs on a Sube's 2.5L engine is good for a vicious migraine headache:eek:....I've had my share of those and don't need any more of them. I do not recommend waiting till you feel deteriorated performance to change spark plugs. This is how you fry your catalytic converter (aka, by blowing unburned fuel through your exhaust). When you refer to copper tops, I'm assuming the typical NGK v power. I wouldn't push those past 30,000 miles. I did a plug change on my 2.5L. There's no need to remove any motor mounts, but you do need to remove the air intake, battery and washer reservoir. It is probably 5x more difficult to change plugs on the 2.5L than my Honda accord and Civic, and probably 2x as likely to strip threads. Link to comment Share on other sites More sharing options...
Gloyale Posted May 16, 2009 Share Posted May 16, 2009 I do not recommend waiting till you feel deteriorated performance to change spark plugs. This is how you fry your catalytic converter (aka, by blowing unburned fuel through your exhaust). When you refer to copper tops, I'm assuming the typical NGK v power. I wouldn't push those past 30,000 miles. I agree. Plugs are recommended to be changed every 30k. Wires every 60k. There is a reason for that. I have seen huge improvements in what were seemingly good running engines from changing plugs and wires. I did a plug change on my 2.5L. There's no need to remove any motor mounts, but you do need to remove the air intake, battery and washer reservoir. Battery can stay there, just remove the intake tube and the washer resevior. Link to comment Share on other sites More sharing options...
timintc Posted May 16, 2009 Share Posted May 16, 2009 I agree with gloyale, just remove air intake from passenger side of engine and the resovoir and you should be done in about an hour. I also have a 2000 Legacy and have done the plugs several times now. The first time will be the most difficult and afterwards it becomes as easy as changing your oil. I have lost the socket down in the spark plug hole several times but now i just use electrical tape and tape the socket to the extension, and i also use an anti-sieze lube before installing the new NGK Copper plugs. Link to comment Share on other sites More sharing options...
davebugs Posted May 16, 2009 Share Posted May 16, 2009 The factory doesn't use anti-seize. I swear the replacement interval has more to do with gaulding than plug performance. Dielectric grease and anti-seize. If that's the same engine in a 2006 Inpreza 2.5 they aren't bad at all (compared to the DOHC 2.5). As stated no need to remove the battery. Don't forget to anti-seize the washer bottle screws heavily. Link to comment Share on other sites More sharing options...
Manarius Posted May 16, 2009 Share Posted May 16, 2009 If I can do the plugs on the SVX without removing engine mounts or paying someone to do it, you can do the ones on your Legacy. Although, I disagree to pull plugs at 30k miles. That seems like a big waste of money on plugs which are meant to last 100k miles. Platinum plugs last that long if not longer. Link to comment Share on other sites More sharing options...
nipper Posted May 16, 2009 Share Posted May 16, 2009 I disagree. I have yet to see a cat go bad on waiting out sparkplugs. Now if you continue to drive on a missing plug, then you can have issues (and that can happen at any time to anyone). And thats not only my personal opinion but professional opinion. SUbaru for some reason likes short plug cycles, where shall we say, more inferior engines of other mfgs tend to push the 100K limit. nipper Link to comment Share on other sites More sharing options...
johnceggleston Posted May 17, 2009 Share Posted May 17, 2009 so if i hated to change my plugs, but hated to pay for it more, what plug should i use for extra, extra, very, very long plug life? Link to comment Share on other sites More sharing options...
forester2002s Posted May 17, 2009 Share Posted May 17, 2009 the replacement interval has more to do with gaulding than plug performance. Gaulding?? What has that to do with spark-plugs? Did you mean 'galling'? Link to comment Share on other sites More sharing options...
davebugs Posted May 17, 2009 Share Posted May 17, 2009 Hey - an English teacher has arrived!! You're gonna be VERY busy around here. Yes - that's what I meant. Link to comment Share on other sites More sharing options...
mikec03 Posted May 17, 2009 Share Posted May 17, 2009 When I changed my plugs [and valve cover gaskets and wires] I put in NGK platinum BKR6EGP plugs. The logic of this was that the 2.5 l engine is prone to tube gasket leaks and I may need to replace all the above in 60-80,000 mi. increments, and I might as well run the put in spark plugs that will last the same time period and do it all at once. Link to comment Share on other sites More sharing options...
Rooster2 Posted May 17, 2009 Share Posted May 17, 2009 Gaulding??What has that to do with spark-plugs? Did you mean 'galling'? Galling refers to the process where two different metals (ie. steel and aluminum, when bolted together, then heated repeatedly want to bond together, and become a bear to separate. This happens when steel spark plugs are bolted into the aluminum head of a Subie. Use anti-seize to prevent galling. I have seen galling when aluminum alloy road wheels are bolted to steel rotors. Remove the lug nuts, then had to wail on the back side of the tire with a mini sledge to get the wheels to separate from the rotor. Link to comment Share on other sites More sharing options...
Gloyale Posted May 17, 2009 Share Posted May 17, 2009 Although, I disagree to pull plugs at 30k miles. That seems like a big waste of money on plugs which are meant to last 100k miles. Platinum plugs last that long if not longer. No way. I pull platinum plugs with only 30-40k on them all the time, and alot of them are burned out. That tiny little platinum electrode melts down into the ceramic. Also, even if they look good, they can be functioning poorly. Plugs are cheap, no more than 25 for all four. Buy them at a parts store instead of from the dealer, but get the NGK (I use the standard v-power for everything) Changing them regularly will yield you that or more in savings on fuel over the next 30k mile cycle. Just change them on the service schedule, there is a reason they recommend it. Link to comment Share on other sites More sharing options...
rainman19154 Posted April 12, 2010 Share Posted April 12, 2010 I'm fixing to do plugs n wires on my '95 lego (2.2L, the usual). Are these as troublesome as the 2.5? Am picking up wires from dealer later today ($50!!! yikes plus tax!!) but will certainly get plugs elsewhere. Anything I need to watch out for? btw I am a believer in treating the threads on plugs. They go in easier and later came back out a lot easier as well. Link to comment Share on other sites More sharing options...
Rooster2 Posted April 12, 2010 Share Posted April 12, 2010 I'm fixing to do plugs n wires on my '95 lego (2.2L, the usual). Are these as troublesome as the 2.5? Am picking up wires from dealer later today ($50!!! yikes plus tax!!) but will certainly get plugs elsewhere. Anything I need to watch out for? btw I am a believer in treating the threads on plugs. They go in easier and later came back out a lot easier as well. I have changed plugs on the 2.2. It is way easier then the 2.5 DOHC. There is more room to work. Nothing special to watch out for. Ditto on treating the threads with antisieze. Sure makes plug removal and replacement a lot easier. Link to comment Share on other sites More sharing options...
Olnick Posted April 12, 2010 Share Posted April 12, 2010 +1 to what Rooster2 said. Yeah, the wires are pricey--but worth it! You might try checking online prices and asking your dealer if he'll match it. Some will do that to keep your business. Good luck. Link to comment Share on other sites More sharing options...
Bluestone Posted April 12, 2010 Share Posted April 12, 2010 On my 2000 Leg. I replaced the plugs with NGK BKR6EGP Platinum tipped, used anti sieze on the threads, of course, and NGK wires...wires cost about $40. The whole process was pretty easy Link to comment Share on other sites More sharing options...
rainman19154 Posted April 20, 2010 Share Posted April 20, 2010 Just a follow up.... I finally did get around to doing the plugs n wires. It was really routine. After looking things over and remembering remarks here, I started on the driver's side. I DID remove the washer resevoir (just two bolts, two electrical connectors and two hoses)... that made gettting in there a no brainer. On the passenger side, I briefly considered pulling the intake but it really wasn't nessecary. I did opt for the NGK platinums. The electrode tip is very tiny compared to plugs I've dealt with in the past. I gapped them to .044". Once I was finished, I immediately went to the local station where I always fill up and topped off the tank. Hopefully I'll see some improvement in the mileage. 16-18 mpg in usual city driving (very much worst case stop n go, stop lights and stop signs in dense urban driving) . If I get onto the highway at all, it does get up over 20. Link to comment Share on other sites More sharing options...
vic/se Posted April 20, 2010 Share Posted April 20, 2010 My 2000 Legacy's Plugs now have 30k miles on them, There are no performance issues yet. Engine runs just fine.How many miles beyond 30k can I anticipate the plugs(NGK copper) going without showing performance issues. When changing the plugs, what problem areas should I be prepared for? What socket extensions will I need to access the plugs and make plug changing easiest? Are the NGK G-Power Platinum Alloy Plugs (BKR6EGP) Good plugs to use? They're resistor plugs, right? I use those on my sub the G-power. the only advantage I see, you can keep them longer, they will go 50k miles at least Link to comment Share on other sites More sharing options...
Recommended Posts
Please sign in to comment
You will be able to leave a comment after signing in
Sign In Now