So right now I have my car at a shop to install my HFPCs. The mechanic is saying that the service manual quotes something like 8 hours to replace the rear pre-cat, which would including removing a tire and possibly a CV axle. Does anyone have some experience putting these on or having these put on that can give me some advise on this? The mechanic is quoting something like 500 to install (which is very high for this guy, considering he installed two mufflers for 70 bucks).

 

yeah, if you go by the book, it'll ask you to remove everything in sight...

- remove strut bar.
- remove jpipe
- remove 4 nuts from catalytic converter
- play tetris to get that sucker out of there. I dropped it out of the bottom, but some super tetris players were able to take it out from the top

 

Any advice I could give the guy other than to play around with it till it comes out? This guy’s a good mechanic and says that it will be pretty tough getting the back one out. I have an FWD by the way.

 

IT IS TOUGH!
I was able to rotate it with the heat shield on and dropped it from the bottom. had a friend guide it from the top and me holding shit out of the way so it could drop out.
Other people on the forum are far better tetris players than I am and had luck removing it from the top.

 

So probably a two man operation? Might have to see if I can get someone else to take care of it. Really didn’t expect a shop to have any issues doing it, I guess they just want to go by the book for safety’s sake.

 

This can be tricky... You WILL have to shop around or do it your self with a good friend of yours. The back if a B:"CH BUT CAN BE DONE. Get different quotes if someone at a shop doing it for less than $300 then just roll with that.

 

Yeah, that’s the bad part about living in a small town... There may be one other guy who could do it here. Lol. I’m down to pay 300 for it, I just want the damn things on the car. I’ve had several people tell me they’d put in those or my j-pipe, neither of which are on yet.

 

That's a bit surprising to me. I guess the official Acura manual for replacing the rear cat might state to remove that much stuff to get to it. However, I didn't do any of that and it took me about 3 hours. Much easier than all that work. I pulled the strut bar off then removed all the coil packs to provide more clearance. That was easy. I also removed the bracket for the oxygen sensor and the O2 sensor from the cat. That's more difficult unless you purchase a 7/8ths O2 sensor socket. As far as I can tell, the O2 sensor is the only SAE threaded component on the car If you have it, removing the O2 sensor is easy. I then removed the 4 bolts that hold the heat shield to the cat and removed those along with the four bolts to remove the cat from the engine. Those are kind of a pain in the neck, getting a ratchet or wrench down in there and having to feel for the bolts at times because you can't see them. Then I removed the three from the jpipe. If the factory jpipe is on, you'll want to spray the bolts with PBlaster before you even start to let it soak. Those can be pretty tough to remove. I had to use a breaker bar. The heat shield that protects the power steering unit was also blocking the cat from coming out so that had to be removed. 3 bolts if I remember correctly, while trying to work around the cat. That was a pain. Then it came out without much trouble.

Install was the opposite direction. Install was as much work as removal sans the heat shield on the cat. I put the heat shield back on the power steering unit. I also wrapped the HFPC's with heat wrap to help lower temps in the engine bay, prior to installation of course. If I were near you, I'd charge about $200 and do it for you.

 

I'm going to try to get in contact with him tomorrow and let him know that it can be done without removing everything to see if he's willing to try it that way.

 

For any mechanic who does this for a living, I think they'd be able to execute this with no problem. Think is, they're not expected to know all the tips and tricks for every make and model of car. They usually reference the tech manual and follow that, which I also do when doing a job I've never done. Show him my post if you'd like and explain that the removal via the top is easier, although it requires a bit of work to locate the nuts and bolts. As a mechanic, doing stuff like that should be 2nd nature.

 

if mechanic is following the book, then of course he doesnt see the shortcuts!
but like you said, losiglow, any mechanic worth his salt would think farther ahead and come up with a trick to cut down on shop time.

 

The first time I swapped out my cats took about 8 hours. Second time took me 4 hours. Theres definitely some tricks to it that shortens the time needed.
I can see why some places charge $500 to put these in, as there are a lot of parts that need to come out in order to install these. Things such as: undertray, radiator fan, strut bar, power steering heat shield, heat shield for both cats, heat shield for half shaft, j pipe.
Advice I would give::​​​

• Presoak all bolts/nuts with PB blaster multiple times
• Theres about 4-5 clips that hold the O2 Sensor wires in place. Make sure to unclip those.
• Remove rad fan
• Remove all heat shields (front and rear cat, power steering unit, half shaft)
• You don't have to remove the half shaft to get it out.
• Front cat comes up, rear cat goes down
• Put heatshields back in last

Then like everyone else said, you start playing tetris with the rear cat to get it out and back in.

 

it's also illegal to remove cats.

 

We don’t even have visual inspections where I live lol.

Looking inside the 3rd cat on the j-pipe and looking at the high flow cats I was pretty surprised by how restrictive the stock ones are.

 

that's not what that means!
since you are replacing it with another cat, you are fine.

but the law says it is illegal to remove cats for the sole purpose of running catless.
and some shops just wont do it.

 

I know, I was just commenting on the fact that no one would care if I ran catless. There are so many old Silverados and F-150s straight piped and loud as hell.

 

Excellent advice. Except I took the back cat up the top. I prefer to work above the car rather than beneath and it appears it can be done either way.

Also, I recommend taking the O2 sensor out BEFORE removing the cat. That might be a no brainer, but I neglected to do it with the front cat which resulted in me having to vice clamp the thing along with PBlaster to get it off. Didn't make that mistake with the rear The front cat is easier than the back even with the radiator fans removed but damn, that EGR pipe was a bitch for some reason. It REALLY didn't want to reattach to the new cat. I was thinking that RV6 might have been slightly off with their design of that connection.

 

I didnt take the o2 sensors out before and had trouble trying to secure the pipe, so it wouldnt move when un-torquing the 02 sensors. I ended up wedging the pipe against some concrete/cement to take off the o2 sensors.

WILL take off o2 sensors before uninstall of pre-cat deletes in the future.

 

That's essentially how I took the timing gear off the front cylinder head I replaced. Except I positioned the head between two pieces of wood and lowered the subframe of the car down on it. I didn't care if I damaged it. I'm only keeping it to demonstrate the valvetrain to scouts since I'm an automotive merit badge councilor.

The ghetto ways us non-pros have to deal with car crap.....

 

whatever works, right?