Spark plug torque question

Hello...

RE: 2000 C70 Convertible.

When replacing spark plugs, how critical is the torque?

Reason, at 75k it's time to replace the plugs, which should be fairly
straight forward. However, I do not own a torque tensioner, just a ratchet
and plug adapter.

I'd hate to buy a tool I'd never use again...if that critical, then for $10
guess I'd better go for it??

 

My sources show that your plugs are the "gasket" type, and the proper
installation is finger tight, plus another 1/2 to 2/3 of a turn.

A torque wrench is still handy for all the other parts on your car.

 

Thank you.. that I can most likely judge...
I do not do all that much on the car.. mostly basics... Plugs are right on
top, one at a time can't be too bad... I've done them on much older cars, as
well as small engines (gapping, etc..)....

It just seems simple enough for me to do, at a much lower cost than a
shop..and it needs to get done...

Thank you!

 

Yeah it's not difficult. I do recommend a bit of anti-seize compound on
the threads, doesn't take much, just a little dab. It's steel threads in
an aluminum cylinder head so you have to be careful not to get it
crossthreaded or over-tighten it, you can strip the threads right out of
the head.

If you're not certain, you can pick up a cheap but usable torque wrench
for under $20, you're still saving money over having a shop do it. You
might borrow one from a friend or neighbor too.

 

Make sure your plugs are spotless with no nicks or burrs and use a copper of
graphite agent on the threads so they are easy to get out next time .

 

Thank you all!
They need to get done, for sure... 75k, getting 'rough'...

 

....if you're not done already.
Some chain auto parts have these tools for loan.
You pay full retail for the tool but when you return it, they give you
all your money back.
(AutoZone does this, anyway)

 

I'm not so sure it is the plugs that are causing the roughness. 75K is
a long time to go on one set, but I do find plugs are pretty well made
theses days.

I don't know your car but the main problems with sparkers are;

1. Dirt outside and inside causing electrical leakage, mostly can be
cleaned along with plug leads and coil packs. Most modern engines are
very good, my partners 323i has had the same set of plugs since purchase
5-10 years ago. It too is rougher but I doubt its because of plugs.

2. Bits break off, seems very rare if engine is operating correctly and
plugs are of good quality.

3. Gaps widen out, can easily be regapped.

I used to be very diligent with my plugs, regular cleaning, replacement
etc, but I havn't found any difference just leaving them alone. The
Engines still get rougher with miles probably due to bearing/piston ring
wear /valve sealing face etc.

 

it used to be plugs, points & condenser -- sometimes a coil. now its
connections, just like a 'puter.

running rough is not something to expect in the first 10 yrs. new
plugs after 75k is overdue (ok iridium's are supposed to last 100k,
but platinum only 50k.)

you have either a b5234 or a b5244 but there are letters & #s after
that which tell the whole story. look @ your vin & post the 6th &7th
digits. then i will be able to give a more complete answer.

try using premium. on race fuel my r purrrrs.

oh the torque is 17 nm.

 

53 are the VIN Digits.. as far as I know, I have the B5234 T3. I bought the
car used a few years ago (long story, don't ask) and don't thing the plugs
have been changed.. not since I have it anyway...

The car is now idling roughly, check engine light started to blink, and now
is solid.. c/b bad gas but I added Super... guess I have to get thru the
tank... it almost at times feel as if it is going to stall.. but after a
while of warming up and driving, drives fine.. it's at an idle, stop, etc,
it seems to want to stall, but doesn't...

Hence why I was thinking maybe plugs?
Most likey due anyway...

 

still replace the plugs (i like the new NGK's & they will work w/ your
engine) . the ce light changes everything. grab an OBDII reader! send
me the error codes. i think i know what's going wrong but i learned
long ago that Myst (my r) is smarter than i am. your car is running
rough because a sensor has failed. fuel is weird. your engine, which
has an ht wants @ least 94 octane. mine wants 108 she's luckily to get
97, but she will run on wet beer farts. your ecu is re programmable. i
know people, in the Netherlands, which can reprogram to accommodate
your driving style.

 

Well... I have cheated lately... we have this thing called a recession going
on, so I have indeed resorted to regular... I topped it off with premium..

I don't have an OB but can certainly get one... I understand some of the
local shops - Pep, etc, will let your borrow one... sensor makes sense
too... I will get over there as soon as I can and report back.. thank you
for your help.. I appreciate it.. if it IS a sensor, is it hard to get to?

Thanks again!

 

the answers are dollars & pennies. & yes & no.

most vehicles can't use premium -- yours can. mpg goes up you save
money.

Myst (my r) has sensors everywhere. some are easy to get to, one is in
the middle of an explosive chamber. get an error code! you can decode
them online. it's all i will do -- of course i tend to know where
things are in something other than cyberspace.

 

I find that mine are usually pretty well worn after about 50K. The
electrodes get all rounded, in extreme cases the ground electrode gets
noticeably smaller from erosion. That said, I've rarely noticed much
difference in performance after replacement but I've never run a set 75K
either.

 

I'm laying low for now.. reason, I may have gotten a bad batch of gas...
once the tank is emptied I will report back.. reason.. light went off.. car
drives ok.. but start up is rough.. check enging blinks.. then after a while
it goes off again...

 

i'm guessing the heater on an O2 sensor.

 

Richard, what I'll do is drive it down, then fill with super...

may take a few days.. then, get and OBDII unit.. (if I buy one, I may as
well get one that can read my wife's 09 Prius as well.... CAN... (the U480
costs about $40.. )

Will keep you posted and thank you for your help!

 

How good are Iridium spark plugs in a turbo Volvo 1990 740 ??????

 

Fancy spark plugs are a waste of time. I've been running the cheap NGK
plugs for years and they've never given me any trouble at all.

 

i'm cheaper. i also value my time & the environment. the amortized
cost of iridium's is lower unless you don't think you'll have your
Volvo for 100k. the iridium also comes from trashed catalytic
converters destined for the landfill, while other metals are often
strip mined.

as for improving performance w/ a turbo. maybe -- probably not. it's
counter intuitive but iridium's spark colder than other plugs. good
for my r but she is dangerously close to dieseling.