loss of power in upper rpms
 

its like it says.. im having a loss of pwer in my upper rpms.. mainly above 7200 and until redline.. and the way it was acting after that rpm was like it was running out of gas but i have 1/2 a tank in it.. has anyone elsed experienced something like this?

my guess on this is that it would be the apy valves? (i think thats what they are called..they open up at 6200)
or it could be the cat... but the power is all there until i hit that 7200 rpm.

i have an '04 MT gt with 64600 on the tac with a reman engine (first one) and theyre is only 9000 on the reman
currently im running 5w30 (just got it changed) but before i was running 10w30 synthetic mobil 1

and yes.. i did search before posting this

guesses.

coils
plugs
first.
fuel pump.

and if they did not clean the apv valves when they changed the engine they should be shot..

but that could be it.

i would go with cat first. then pump.

beers :beer:

yeaa but with a cat.. wouldnt it be all through the rpms??? and not just at that certain point? bc the cat would most likely be clogged and i wouldnt really get any power after 30mph when they replaced the enginge they replaced the coils,plugs and wires as well

nope.

cat controls flow. less flow no problem. more flow something has to give..

the cat does not know mph. just flow.

beers :beer:

okok.. good to get that cleared up.. i may let the dealership look at it tomorrow..see what they say.. theyre usually pretty good bout warranty work and everything... and it also helps to know people up there.. i have to go up there anyways for an rotary event with the rx8's.. theyre showcasing the R3 if im not mistaken

Have you seen these two "TSB's"....

http://www.finishlineperformance.com...14-08-1924.pdf

http://www.finishlineperformance.com...13-08-1925.pdf


But I hope it's your cat...

yes i have.. i had the msp16 done when it first came out... and it doesnt feel like its losing power at all from rotors failing but more like its choking from not getting enough fuel. but it could be the cat too.. idk its the first time its ever done this but it actually does sound like a fuel pump issue the more i think about it...

or it couldve been the heat i did drive it for 3 hours from miss. to my home in AL.

Did you ever figure out what the problem was?

I don't know if it has to do with the 90+ degree days we've been having or something else but I've been noticing intermittently a slight drop in power at WOT around 7800 to 9000 rpms. I just changed my spark plugs, which made everything smoother but I'm still getting the high rpm loss of power SOMETIMES. Could it be the turbulence not being straightened out by the absence of the first screen in my intake bell/horn, the extreme heat not allowing enough oxygen at high rpms, coils need replacing maybe? Fuel filter? Clogged CAT? PL0420 came up for about a week and went away a little over a month ago.....any thoughts?

Please give us the history on your car, year MT/AT,miles etc just anything you can add... The service it's had parts replaced. Have you Seafoamed it?

Had the car about 6 months. 54k then, 66k now. '04 mt all stock. just replaced plugs 3 days ago... this is me from another post:

on my way home tonight, the revs stopped at precicely 9k in 2nd about a mile from home. A code flashed and then remained on. Assuming its the pl0420 again... When I got there, I remembered reading on here about checking the CAT right after hard driving, so I did just that and found it to be glowing orange on the hot side. My buddy looked at it as I redlined it and said it got a little brighter when I did that. Tomorrow i will call a local dealership to inquire about the 80k CAT warranty. If that doesn't pan out, my buddy has a couple high flow CATs from his 2nd generation rx7 drift car. Any quick suggestions b4 I call the dealer in the morning? Dont' want to go up in flames.... :SHOCKED:

P0300 Random misfire detected Flash/ON 1 or 2 Misfire This is the code I got when I went to autozone. Lucky for me, the guy who helped me is an RX7 owner and seemed to know a lot about 8's as well. He reved it up and said It's only missing at high rpms, causing unburnt fuel to enter my cat. He said to swap the coils around so that the leadings get switched with the trailings, of course keep the wires in the same locations. I'm going to try this and take note of how many coils if any I need to replace...I'll go ahead and replace the wires too...the auto zone guy also told me I should order some Idemitsu premix specifically for 8's. Anyone ever used this stuff? I'll let you guys know what happens with the coil rotation.....Thanks :smoker:

^^^^ WTF.....

If the coils are shot then REPLACE ALL 4........

This isn't not a car to go half ass with maintenance ...


miles and history?????????

yea I got some rx8 idemitsu sitting right here.

I'll sell it to you... oh wait hang on let me write rx8 on it so its rx8 specific.

Now onto your coils just buy new ones.

It could be plugs wires or coil packs. if you got the money buy the BHR kit. if your broke buy the OEM ones. If your super broke save some money up. There really is no point in replacing 2 or 1 or 3. Just do ti all at once.

P.S. if you didn't get my hint at sarcasm all idemitsu premix is the same across the board. and I highly recommend it. use a half ounce to a gallon or 7 ounces per fill up.

Sounds like fuel pump to me.

did you ever hear back from the dealer about the APV's? You can run a Diag on them by taking off the motor and manually moving the gears. if you hear the valves turning fluidly and they aren't getting stuck you should be good.

If its hard to turn or they get stuck they need to be serviced.

https://www.rx8club.com/series-i-trouble-shooting-95/coils-cats-question-199713/

Check out this thread. I kinda moved the conversation to that one. Gutted the cat and all is right with the world....4 new coils and wires are on the way. Plugs less than a week old.

Since the APV motor can be tricky to remove with the manifold still in the car, you can also disconnect the electrical connector to the motor and apply 12VDC it.
Then swap the wires to reverse direction.

Here are a couple pics showing where to attach the wires:
Attachment 158201 Attachment 158200
I have this wired to a DPDT Center-Off switch to easily change polarity so I don't have to remove the connectors and swap them to change direction.
This way I can quickly cycle the valves back and forth.

Nice! that's about a million times easier.

Yup... I did this a few weeks ago on someone's car.
You can still hear the valve cycling pretty easily too... so you're not guessing if the valves are moving or not.
And it was easier to do this while in the engine bay instead of through the wheel well so you can actually see the contacts on the motor.

Nice! I never got to test the clearance in the engine bay can the Manifold even come out without pulling the engine?

Its been done before... but its a PITA!
Here are the basics not including the removal of various hoses and such:
1) You'll need to separate the motor from the mounts.
2) Move the motor all the way to the driver's side.
3) Unbolt the LIM and slide it out towards the passenger side as far as it'll go.
4) Remove the cover/gasket on the LIM and slide that towards the engine.
The cover can't be removed because the APV valves are still inside the engine.
5) And the tricky part... remove those tiny bolts holding the APV valves/barrels to the rack (and try not to lose them since they are unique shoulder bolts).

Shit Id rather pull the engine. only takes 5 hours total to pull and put back in.

What if CAT has been gutted & sometimes, not all the time,car still acts like it loses power & really wants to die,(sometimes does) & after about 5 minutes crank it & it acts as if nothing ever happened? When it runs,runs great,but sometimes after about 20 minutes it just acts sluggish,running 93 ,plugs,wires,all thats new,please do tell if you have had this problem or ideas to try.I am new to this so if it is other threads,I do not know where they are..its a 04 manual trans with 107,000 miles...I know right? I drive the crap outta it=)

You should get a compression test, I'm guessing you have extremely low compression.

Have the coils ever been changed? Have you tried a de-cabbon cleaning?