Whats wrong with my engine?
 

Hi, I have just bought an Rx-8 and it seems to have a problem with the engine, first of all it takes 3-5 seconds to start, and has poor low end power and acceleration, like pulling away in first it is quite slow untill revving above 4000.

Acceleration is also jerky up untill 4000rpm, then the engine is smooth again but not much power most times, then sometimes the power feels fine abouve 4k!

Anybody have experience with this before, could it be the coils or something like that. It's a 2004 with 99000miles and fsh.

coils, plugs, how is the cat

Not mechanically minded really, how would I check the cat?

unscrew and have a look inside

Had my mechanic look at the engine, He pulled the plugs out and said they looked rusty!

Also did a compression test with a standard piston tester, he got 5bar (72psi), I know you need special rotary compression tester to be precise but would the piston tester be kind of accurate??

thinkin about doin the seafoam trick also to see if that helps.

mickrod where you from ?

He probably chose that Irish flag because he's in Ireland. Just a thought ;)

First off don't drive it another 1000 miles if your in the US w/ the standard 100k warrenty. You'd be a lucky bastard if you have a failing engine and can get a free replacement before it runs out. That'd be my dream situation if I ever get up to 99k

^He's in Ireland. That warranty only applies to North America.
Rusty plugs could mean that you have a coolant leak into the rotor housing. This could cause the engine to sputter until the coolant was cleared. This may not show up on a compression check. You would have to let the car set overnight, remove the spark plugs, then turnover the engine on the starter. If any fluid came out, you would have verified that this is the problem.

^Great suggestion!

The OP hasn't checked back in...

My initial suggestion would be to check/replace the plugs, wires, and coils. From my experience and research, "rusty" looking plugs isn't really atypical in the RX8. I've seen guys put their new plugs in and within 100 miles they look a little "rusty." I would start with the ignition system. That at least sounds like it's where your problems are coming from, then move on. The prolonged effort to start the car kind of leads me in that direction.

I dont mean to thread jack im having almost this same issue with my AT 05 with 71,000 miles i have extended warranty until 75,000 for powertrain i just replaced wires,plugs,coils i am having same starting issue and bad (sometimes no idle just dies until giving some gas)idle after cleaning MAF(i was very careful cleaning with qtip and alcohol) the idle got even worse after i bored out my stock cat. Where should i look to first MAF,starter,cat please help.