Rep Power: 0

I need to change the spark plugs on my 05 Civic EX. I will have to do so outside. I know that the engine should be cold for hours before doing so, but can it be too cold to change the plugs? The temperature here was in the teens overnight and is currently is around 35. Should I go ahead and change the plugs or should I wait for a warmer day?

 
Rep Power: 367

as long as the dong don't shrink too much with the cold, i would go anytime...

 
Rep Power: 243

Things seem to come apart better when it is warmer but anytime you want to give it a go. I would wait but I don't like the cold lol.

 
Rep Power: 133

This is one of my favourite maintenance repairs to do so I would wait for a warm comfortable day and enjoy it. Use OEM NGKs.

 
Rep Power: 518

Why?
The correct Platinum (and Iridium) plugs last almost forever so if it's just for maintenance I'd wait until it's nice and comfortable outside.
OTOH replacing spark plugs shouldn't take more than 10 minutes IMO

Who says so?
I rip them out of screaming hot engines all the time. No problems.

 
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I'm having what I believe to be misfire issues. If I'm going to pull them to inspect them, I figure I ought to replace them, especially since they're pretty cheap.

I've read in several places on this forum and elsewhere that the engine should be cold. Doesn't seem like a standard for everyone, but I always try to abide by the "better safe than sorry" philosophy.

If you're talking them out "screaming hot" all the time, doesn't that go against your "you should never change them" logic? (or are you being sarcastic?)

 
Rep Power: 518

Got details about this? Got codes and freeze frame data you can post?
I think General Motors had that in their service information for many years, but I've never seen that requirement written in Hondas service information.
Remember, I fix cars for a living. Yes I routinely replace spark plugs, and in my world we don't always have time to wait for an engine to cool down.

 
Rep Power: 0

Fair enough. It hadn't occurred to me that you fix cars for a living.

I'm not getting codes associated with misfires. I didn't realize that there were codes for that. (My prior car that had the issue never showed codes.) The car has been sluggish and the engine seems to be pulsing lately. I haven't had the car for much of its life and I get the impression that it hasn't ever been tuned up. I figured that I would replace the air filter, plugs, PCV valve, and possibly the ignition coils first to rule out misfire issues. It's at 132K miles at this point and it seems that, since I don't know whether or not it's been tuned up, and most of these things (besides the coils) are pretty cheap, that doing so now would be a wise first choice.

 
Rep Power: 518

Check engine light works? Check engine light does not stay on while driving? You've actually checked it for fault codes and there are none?
Then your problem is not likely to be a (major) misfire.

Year, make, model?

If the car has always been this way since you've owned it, You may want to drive a couple other identical cars so you can see if what you feel is typical and not a real problem with the car.

Personally, I'd zip the plugs out and see what they look like....and note if they are obviously not OE. Replacement schedule for the (correct) plugs was every 100,000 miles or so.

Timing belt ???

Not a high failure item. I would not replace until there's a failure.

Recalls up to date?

 
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Yes, the check engine light works and yes I have had it checked recently. P0497 came up a while back, but nothing else, I don't believe.

Prior car with misfire issues was a 90 Subaru Justy.

I have two Honda Civics, one 2001 and this 2005. They drive very differently.

The timing belt was done sometime before I bought it a 104K. There is a sticker under the hood signifying that.

It is up-to-date on recalls.

I have to mention that the car did recently have the head gasket replaced, which I certainly attribute to the issue. The issue started when I got the car back from that repair.

 
Rep Power: 518

Check if timing belt was not reinstalled correctly? (out of time by a tooth or two)
Valve clearances incorrect?
Ground wires weren't left loose? (see post here: https://www.civicforums.com/forums/3...ml#post4758108)