Honda R18Z being sluggish, and other civic problems

Dana has had her 2012 civic since new, it now has 152k on the clock. Hasn't had any major problems. New muffler and resonator, brakes, a battery, and a control arm have really been the only repairs that I remember. 

Starting last year, I noticed it getting sluggish. First on steep hills, and now on flat land too. My initial thought was cat, but it still hasn't thrown any lights and the mileage is staying roughly the same. 

I don't know the last time it's had its plugs changed. I popped the hood today to check them and couldn't find them unless they're under plastic. I'll look a little deeper tomorrow in the driveway with tools.

Now while researching if it was an interference engine or a chain vs belt engine, I found out its drive by wire, "programmable fuel injection", and has some sort of dual stage variable intake manifold (wtf?), and requires a valve adjustment every 25k. I still don't know if it's chain or belt, or interference, but I guess there isn't a butterfly that needs cleaned or anything simple like that. 

Should the car be my main suspect? Does the Ivtec that "shuts off 4 valves at low rpm for economy" shut off with the eco mode button? 

Basically, I've tried ye olde Italian tune up and had no luck. 

It does have another issue, this one related to braking. I replaced front pads and rotors last year, about 8k miles ago. Did nothing with the rears. At 20mph, while turning, I'm getting a slight rumble from the rear passenger wheel, and at any speed the pedal feels like E36 M3. It's not going the whole way to the floor, and the fluid reservoir looks good, but it's not stopping very well. Double tap the brakes to downshift then pump them once or twice while coming to a stop. I don't think it could safely panic stop currently, and I've come very close to needing it to driving through Pittsburgh the last couple days. 

My plan tomorrow is to get it onto jack stands, check the fronts are still good because front driver is squealing like a pig, then dig into the rears to see what's up with them. Maybe do a fluid change, definitely bleed them all around. 

Sorry for the giant wall o text, just trying to get all the relevant information out that I can in the first post. 

Wow, not a single reply. Cool.

This was the best of the 4, yes, way past due but done before. Installed NGK iridiums, and it's a little better, but still a lot of flat footing just to get around. 

What can I do to test the coils? Is there even a chance they'd be bad while not throwing codes? It's going to be a $500 catalytic converter isn't it? 

What's the secret for getting these drums open? Definite rubbing noise with the wheel off, I got new springs and shims but nobody has a wheel cylinder until at least Monday so probably next weekend before I can get into them.

I watched a couple videos and saw guys threading bolts into the holes on the face, of course they're hidden in the shadows in this picture. I have zero hardware that fits the threaded holes, any clues on that thread size? The videos didn't mention what sized bolts they were using, and I didn't want to just pry and risk breaking one because, surprise surprise, Canyonero is running strange now, and I cannot afford to have both vehicles down. 

RE; Drum brake-there should be a bolt somewhere on the car you can remove and thread into that hole. Definitely beats prying. WAG M6 ? Looking a little rusty .

RE; Sluggishness.  My best guess is the VTEC solenoid is gummed up with oil sludge. You could try removing it, and cleaning it out with carb/ brake cleaner, or just replacing the thing, depending on your budget. Seafoam can clean up sludge, but you know about those miracles in bottles. A valve adjustment is a really good idea, too.

I've got an 08 with an R18, I don't know if it's the same one as yours.  I thought that the valve adjustment interval was 100,000 miles.

In reply to Floating Doc (Forum Supporter) :

What I've been able to find is just a software difference between the R18A, 06-11, and R18Z, 12-14. Just enough of a difference that Hondata was only "considering" making stuff for them, but physically they should be abbot the same. But all the forum posts I've stumbled across end in like 2014. 

My '06's drums just pull straight off, no retainer on any kind.  Might be rust bound around the center hub, but you should be able to shock that free with a hammer or (better yet) pneumatic hammer.  There is a star wheel adjuster accessible thru an oval shaped hole on the upper half of the backing plate if you need to back off the shoes a bit.  Hole may have a rubber plug in it.

Definitely go thru the valve adjustment routine.  Get a new valve cover gasket (the Fel Pro blue one is a good choice, or OEM) before you launch into that and some RTV for the corners (if memory serves).  

VTEC  valve should be on the firewall side of the head if your engine is still like mine in that way, on the passenger side.  Get that gasket also (only use OEM) if you intend on pulling it, and kiss some on the skin on the back of your hands goodbye because you'll likely lose some during that job.  

While at it, pull the EGR valve and clean that passage, and replace that gasket.

Hope this helps.

I forget what year range, but around this year I've seen a lot of Civics with torn intake boots. Check your intake boot for cracks, air leaks post-MAF are no bueno and will cause a lack of power.

It has a chain. 

Hondas like their valves adjusted often. I bet they are loose, while getting them in spec will make it drive better and increase fuel economy it will not transform it onto a F1. 

These cars are SLOW. My mom has a 2007 from new with 270k miles that she adores and does not want to get rid of. 

Variable length intake manifold have been used since I can remember. SHO with the Ford/Yamaha engine, Toyota T-VIS in the 80s, etc. Nothing new or scary there.