WRX tune-up question

[David Edgley]

My silver 2004 WRX just had its 30k mile service. Prior to the service, I
had noticed what felt like surging and lack of power under hard
acceleration. The tune-up included:

air filter
spark plugs
fuel filter
fuel injection / combustion chamber flush

Today I was able to play a little on the way home from work and my little
WRX drives like a different car! The surging is gone and the acceleration
is MUCH improved. So - did anything in particular make the difference? If
so, I might want to have it done before another 30k miles! Your advice is
appreciated.

David
stock 2004 WRX, 5-speed

 

[John Reece]

Plugs at 30K? I'm guessing the fuel filter, or fuel injection service..

 

[mulder]

You do realize that the plugs aren't required to be changed until 60K in
the WRX?
It's possible that you had gotten some lousy gas and the fuel filter was
clogged, that might have been the reason for the poor power. I really
doubt that the fuel system flush had anything to do with it, this is an
unnecessary service that is typically forced on you by dealers looking
to make some extra money at service time.

 

[y_p_w]

Plugs at 30K? I'm guessing the fuel filter, or fuel injection
service..

Yeah. At that price, they better last the rated 60K miles. I
doubt a fuel filter needs to be changed that soon.

An air filter is so easy to change yourself and so cheap that
changing it every 15K miles might be a good idea. I bought a
bunch of OEM air filters mail-order for $10 each.

 

[David Edgley]

Yes, I realize that the service interval on the plugs is 60k miles. I
reasoned (perhaps in error) that if they needed to be changed at 60k, I
would rather not be driving on plugs that need to be changed. So I asked
that they be changed early. On the subject of the injector flush - I
complained and they took it off my bill. When the service consultant was
going over the items in the 30k service, he neglected to mention the flush.
When I picked up the car and saw that extra $120 charge, I complained. The
service manager showed my my signature authorizing the work but refunded it
without arguing. I guess they want me to come back. Concerning the gas, I
almost always buy Chevron and ALWAYS buy premium.

Anyway, I was (and still am) curious about what might have made the car run
so much better but from the responses so far, the suspects seem to be the
air and fuel filters.

Thanks for the help - this is a great newsgroup!

David

 

[y_p_w]

Yes, I realize that the service interval on the plugs is 60k miles. I
reasoned (perhaps in error) that if they needed to be changed at 60k, I
would rather not be driving on plugs that need to be changed. So I asked
that they be changed early. On the subject of the injector flush - I
complained and they took it off my bill. When the service consultant was
going over the items in the 30k service, he neglected to mention the flush.
When I picked up the car and saw that extra $120 charge, I complained. The
service manager showed my my signature authorizing the work but refunded it
without arguing. I guess they want me to come back. Concerning the gas, I
almost always buy Chevron and ALWAYS buy premium.

Brand name is no guarantee that the tanks don't contain crud. Also - an
excellent plug such as NGK platinums should easily do 60K miles. 60K
is probably slightly conservative. I recall pulling some original
Denso platinums at 70K miles, and they were perfectly gapped with no
electrode erosion.

Anyway, I was (and still am) curious about what might have made the car run
so much better but from the responses so far, the suspects seem to be the
air and fuel filters.

Air filter is cheap and easy to do yourself. NGK platinum plugs are
about $12-15 each and a pain when it comes to installation.

 

[mulder]

It's good that you were alert enough to notice that and get your money
back. Unfortunately this type of thing is very common with
dealer-performed services. They frequently add extra and generally
unneeded procedures to pad the bill. Your best protection against this
is to bring along a copy of Subaru's recommended services for the
mileage your car is at, and insist that only those services be
performed. If the dealer refuses to comply or insists that their extras
are really necessary, leave and go elsewhere. You also have the option
of doing the maintenance yourself, it isn't all that difficult. As long
as you keep good documentation of what you do your warranty won't be
affected.

 

[DG]

My silver 2004 WRX just had its 30k mile service. Prior to the service, I
had noticed what felt like surging and lack of power under hard
acceleration. The tune-up included:

air filter
spark plugs
fuel filter
fuel injection / combustion chamber flush

Today I was able to play a little on the way home from work and my little
WRX drives like a different car! The surging is gone and the acceleration
is MUCH improved. So - did anything in particular make the difference? If
so, I might want to have it done before another 30k miles! Your advice is
appreciated.

David
stock 2004 WRX, 5-speed

It's a good thing you don't have a 2005 WRX that "needed" a fuel filter.
They are part of the fuel pump and much harder ($$$) to get at. No easy
underhood replacement.

DG
'05 WRX Sedan, premium edition, WRB (of course)

 

[marcwert]

I have 97 Legacy 2.2 with 100K Mi. When the NGKs Copper start to round
the electrode at 30 K Mi it hesistates and has no pickup. Last time it
was new plugs and wires and it ran better, but now it vibrates at idle
while stopped with the AT in drive. Idles at 600 RPM sometimes hits
1000 RPM. Something else is wrong. Also i have the psiton slap or what
ever Subaru blames it on. my last Subaru. the car is not too bad, but
the importer stinks

 

[TG]

Perhaps the marginally sized filter, Turbo cars suck a lot of air thru the
filter. Next time it seems sluggish take a short spin without the filter and
see how it feels...in a clean environment of course. TG

 

[james]

any chance they revised your engine software??

any chance it is a combination of everything, including
re-set your tire pressures (which can also help)???



jellymax

(don't fry any wooden fish)

 

[Bryan Lee]

NEVER RUN WITHOUT AN AIR FILTER!!! Doing that you can hurt your motor.

 

[y_p_w]

I have 97 Legacy 2.2 with 100K Mi. When the NGKs Copper start to round
the electrode at 30 K Mi it hesistates and has no pickup. Last time it
was new plugs and wires and it ran better, but now it vibrates at idle
while stopped with the AT in drive. Idles at 600 RPM sometimes hits
1000 RPM. Something else is wrong. Also i have the psiton slap or what
ever Subaru blames it on. my last Subaru. the car is not too bad, but
the importer stinks

I got corrected on this once, and never forgot. "Copper plug" is a
misnomer. A standard plug's electrodes are made of some sort of nickel
alloy. It's the core between the connector and center electrode that's
made of copper. I'm pretty sure that most platinum and iridium plugs
use copper cores too.

 

[CompUser]

NEVER RUN WITHOUT AN AIR FILTER!!! Doing that you can hurt your motor.

....or destroy your turbo in an eyeblink.