LoSx

I did a compression test on my engine to see if I should invest into the car because I need to replace a bunch of stuff...

Its a 2007 with 36K miles (not much) on its 3rd set of coils and 2nd set of plugs (reused plugs one time) and 3rd set of plugs

It also has a dead cat.

On to the numbers:

Rotor 1 (Front)
7.1, 7.1, 7.1 259 RPM

Rotor 2 (Rear)
7.3, 7.3, 7.1 258 RPM

Altitude is 450' above sea level not sure if they corrected it as they gave me the numbers in some excel sheet that mazdausa provides them but they said the engine is good. The technician said that I would be wasting money doing the compression test because he could tell it was good based on all the other rx-8's they have diagnosed.

Now if I am reading the sheet correctly at:
RX-8 Help

It looks like it is bad but the tech was telling me that these numbers are pretty good and that usually when they have a bad engine the are in low 6. Does then engine seem decent enough that I should justify spending a decent bit (around 2k in maintenance parts) or should I be looking at getting a new/remanufactured engine?

I'm not sure if I should look at getting a new engine now or just keep driving and wait for it to go... It seems to drive mostly fine and the tech said it just needs new wires and spark plugs again and coils are fine. I am thinking of finally going BHR kit so it stops hopefully (As you can see I don't put a ton of miles on it)

9krpmrx8

iTrader: (46)

The tech is an idiot and that engine is barely passing. There is no usual bad engines, only varying degrees of a loss of compression.

LoSx

That's the sheet I linked and yeah unless I was missing something that's what I was thinking as well... even if I correct for being up 450 feet it moves the numbers to 7.2 or 7.3 instead of 7.1 but still seems like on its way out. Any idea how long I can expect on the engine? The care still idles fine and runs fine so I am hoping I get some more time out of it...

Loki

iTrader: (1)

You said the cat is dead, meaning you took care of it or you're driving around with a dead cat?

9krpmrx8

iTrader: (46)

It's a crap shoot, it could last a week or it could last another 10000 miles.

LoSx

I was driving a bit quick on a cool night and WAM out of no where.... I was going to bury it but... well its under the seat in a bag and smells terrible...

Actually the catalytic converter burned up one day when the car misfired badly (I drove it a mile home) and the internals disintegrated and sounds like marbles rolling around the exhaust when I stop/start. But they gave me a quote of 4900 to fix the issues with the car and said the engine was fine... I said no thanks I'll take it back.

Now just gotta figure out if I should spend 1500 on new brakes all around (potentially rotors), front tires at a minimum, cat (BHR hi flow catalytic converter maybe), ignition coils, wires and spark plugs knowing the engine mail fail on me... or if I say f*ck it and buy a different car...

Also got to get rid of that damn cat skeleton in the back... ugh the smell.

Loki

iTrader: (1)

So did they empty out the cat pieces from the exhaust? Because that'll kill your engine in damn short order.

LoSx

No I am going to have to clear out the pieces from my exhaust... I figured it shouldn't take long to do just annoying in the cold weather when you don't have a garage, didn't realize it would kill my engine faster... I better get a move on. Guess I just have to make a decision on what to do... but I'll probably drive it til it gets unreliable and then put a rebuilt ported engine in... or if I can come up with the cash an engine swap to a different platform 13brew...

Loki

iTrader: (1)

They probably should have informed you of possible consequences. If you gut the cat and cleae the debris out of the exhaust, you can keep driving until it gets unreliable, which could be years at your rate It's not in great shape, but it's not dead yet.

Chrishoky

iTrader: (9)

Also, your maintenance costs are way high. Dont pay for the dealer to do any of this work, they will screw you on this. Most of these items can be done for a fraction of the cost in your driveway in under 2 hours. $1500 on OEM brakes? Please do some reading...

9krpmrx8

iTrader: (46)

$1500.00 is about what I paid for my Racing Brake BBK front and rear.

LoSx

Yeah of course those costs are insane... also the dealership I go to (only one nearby) has got to be the worst dealership of them all. My compression check and the multipoint inspection that they do cost me 270 when I picked it up... Roughly double of a better dealership..

No way I would have them touch my car... Ill do my own work... Just debating how much I want to put into a dying car... But a new engine on a fun car is a lot less then a new fun car..

Steve Dallas

At 36K miles, you do not need new rotors. It probably wouldn't hurt to have them turned at $10 to 20 each. New OEM pads are ~$150 per set online (parts.com). A brake flush typically costs $90. Additional labor should not be more than 1 hour at $90. So, you need about $410 in brake work, plus tax. You can do it for a lot less if you can manage your own labor and use less expensive, name brand brake pads from Rock Auto or wherever.