Rx8Burton

I have a 2005 rx8 with roughly 85k miles. Recently I've been having an issue where it doesn't want to accelerate properly. It starts and runs fine. As soon as I put it in drive and start to go, it doesn't want to accelerate. I can rev it fine until it starts to really move. When I get moving it struggles to go. Doesnt have issue staying running. Just doesn't seem to want to get up and go. I can only rev it to 5k rpm and then it doesn't want to go past that. Takes about 5min to get from 0-60 maybe even longer. Again, no idle problems, misfiring. It does have new coils and wires. I should add it will rev fine in park but not after driving 5 ft.

jcbrx8

Do you have a CEL? If so, get the code read. It will provide t-shooting direction.

My hunches based on the limited info you've shared are:
- a clogged cat
- issue w/new coil, leads ,or plugs
- or a stuck "open" SSV or APV valve

Rx8Burton

I dont have a CEL. I did have a buddy of mine pull the codes and it said I had a clogged cat but I wasnt sure if it was reading properly due to the aftermarket exhaust on my car. I'm sorry for the limited info. Would any other details help?

CaymanRotary

The cat is separate from the exhaust. It’s the part just before the aftermarket exhaust starts. Looks like a cylinder. There is no code for a “clogged cat” it must be removed and visually examined. If it’s clogged you have 2 options:

Purchase and new cat from Mazda. Be warned, last I checked it was north of $2,000.

purchase a midpipe and a cheap replacement cat (if you have emission requirements). This way you just swap the cheap cat for the midpipe after you pass emissions. You could have a muffler shop fabricate a midpipe for you or can buy an aftermarket midpipe. Total cost for both the cheap cat and midpipe with installation roughly $400-$800 depending on what you decide.

jcbrx8

First, if it takes anywhere near the duration of time you say 0 - 60 mph; don't drive it until the issue is resolved.

Edit: So, you have a buddy who pulled codes indicating it has a clogged cat. Not sure how you didn't think that was important?

Have you checked your cat since your buddy pulled code indicating it was clogged?
You said it had new coils and leads. You know...bad ignition (coils, leads, plugs) kill cats. Bad cats kill engines.

So, definitely need to check the health of your cat immediately. Just separate your midpipe from your down pipe. Let it hang a bit, and inspect the substrate with a flashlight. It should look like really tight honeycomb material. If not, it's toast, and needs replacing.

If you have questions about what the substrate should look like, Google "catalytic convertor ceramic substrate".

All the best.

Rx8Burton

Whatever it was he used did say clogged cat. I'm not sure exactly what he used. I guess I'll start there and move forward. Thanks a load!

Rx8Burton

Thanks a load! That's where I'll start on the car. It's parked up right now. I'll update on if that was the issue!

Rx8Burton

So after a month of trying to get this up on the lift I was finally able to. Turns out that it has an aftermarket cat delete. I'm not sure what my next step is here. The car is not currently able to be driven. Any ideas on where to go next?

CaymanRotary

Did you ever get a compression test done on your engine? Also see you never changed out spark plugs. Maybe pull the existing plugs and inspect. No engine codes at all?

Rx8Burton

No engine codes came up when my buddy hooked up. It said clogged cat and something else. Someone said maybe my alternator bracket could be bent. It's never had any problems actually running or at idle so I never thought to get a compression test because it never seemed like a compression issue.

CaymanRotary

If there is no codes its difficult to provide much help because it could be any number of things. A compression test is a good place to start because then you will know if its the engine itself that's causing your issues. You should also hook up a scan tool and read us out any engine codes that pop up. You did mention "something else". What's the condition of your spark plugs?

Rx8Burton

Well thank you so much for the help. I'll try the things you have suggested. Great community here! Thanks again

Kimura

Have you checked your air filter?

Rx8Burton

I have. I have a cold air intake on it. I pulled that all apart and couldn't find a clog but I was suggested to check the airflow sensor.