i have a 2004 that had the motor replaced at 90,000 miles, but of course all of the other stuff (alternator,starter etc) stayed the same (old) now i have a problem where when i first start the car it will rev up fast and normal,but it seems after a non specific amount of time it will just stop letting me rev above 3000-4000 rpm, not a str8 cut off mark just hovers around there depending on what gear im in and if im in neutral it takes a good 5-8 sec to reach 3500 rpm............i replaced the gas pedal from the advice of a mechanic ( he said the drive by wire systems sometimes go bad) then that didnt work so i replaced the throttle body (also on advice from the mechanic) still same problem. NOW IM AGGRAVATED. Does anybody have a idea what this might be, or any trouble shooting test i could do so i can stop spending money on **** i dont need

 

I have advice:

Stop using that mechanic.
He obviously doesn't know what he's talking about, and its costing you money for no good reason.

How old are your ignition coils, spark plug wires, and spark plugs?

Hint - If you don't know the answer to that question, you should replace all of them, today.

BC.

 

^good advice

 

He didn't really bring the car in and do a good testing, he just ran the obd scanner and suggested some things to do....but the coils and plugs were replaced with the new engine I would assume, iv searched on here also and found something about the OMP....one of the reasons he said to replace accel pedal and throtttle body was because the scan tool said something about voltage too high in intake controll solenoid ...sorry for the quik reply, on my phone

 

Sounds like a bad misfire. Take Bladecutters advice.

 

when did this start? RIGHT after replacing the engine? or sometime after?

 

sounds like you are in limpy-d1ck mode, did you swap the OMP over as well?

 

When I had my motor replaced by the dealer back when, they didn't replace the ignition system - I had to specify that I at least wanted new plugs; you got a lot of paperwork after the swap so check it, if your coils were replaced it will be on there, separate from the engine. Though IMO it doesn't sound like an ignition problem unless they totally facked something installing it.

 

:update

 

Sorry guys new baby on the way and life in general kept m from updating, I'm going to the dealer on wed. But it took about 6 months after the new engine was put in to act this way, yes new plugs and they kept my coils but I had just purchased them 6 months prior to the engine swap (1 yr old now), odd thing is that if I. Let it sit then start it upit will rev normally untill about 30-60 sec go by the back into (what I think I have found out ) limp mode.....anyway i m tired of dealing with it, new car on the way and the 8 is heading to daytona mazda for a troubleshoot, hopefully if its something like the omp it is covered under my new engine warranty......sorry for spelling and gram , sent from the cell

 

Cat is gone, and the fuel pump is possible I guess

 

i did , and i forgot them, but the main one said something like air intake control valve (or) solenoid circuit low

 

the cel came first then a few weeks later the problem began

 

Just for the heck of it, have you tried the brake pedal stomp 20 times reset yet?

BC.

 

Nope, I left the neg batt post off for a week, figured that would reset everything.......oh I just remebered, after the car sat for a bit with the batt still connected it was dead and it never did that before the problem, but hen again it never sat that long because I drove it daily, it was only 4 or 5 days tho so its still odd......wonder if its related

 

I wish I had 1/10th the knowledge you do about these engines.

Anyway...


FoxRacer600RR:

Turn your ignition key to ON
Stomp brake pedal 20 times, as quickly as you can.
Depending on when you car was built, the oil pressure gauge might sweep, or it might not.
Start engine.

That will reset your e-shaft profile, and possibly clear out the original profile that is stored in your computer's memory from your original engine, that your dealer might have forgotten to reset when they replaced the engine so many months ago.

BC.

 

ok guys, you will never beleive this .......top pic, tan/red pin slightly pulled out



the tan/red wire in between the whit/blue and black/white was un-pinned!

i took it to the dealership and the tech took 2 hours too scan and test everything and he came back and told me that he thinks ECU harness is faulty, and we of course started talking about prices. well for ***** and giggles i asked if i could open the ECU box on the left of the engine compartment and check the plugs for myself, and he said he had already did and that is not the problem because if the plugs were unplugged the computer would not connect and read, well sure enough if unplug all the flugs and find one more under the silver box and BAMMMMMM un-pinned tan red wire

 

i also have no CEL @ all, its been a looooong time since i saw that. BTW does anybody know where i can get a ECU pin config guide to figure out what pin that was, just curious

 

http://foxed.ca/rx7manual/manuals/RX-8FSM/

Go to Electrical pdf

 

you sir are awesome, thnx

 

holly shi** looked thru all 148 and the only one that looked like it may be it was at the bottom of 147 but not sure, il finish the searching tomorrow

 

So i am having the same sorta of issues when I first purchased the car the guy said it was a bad air pump but as I was driving it home the car would not go past 4k rpm’s and had the slowest acceleration ever so I plugged the obd2 in and it’s gave me a bad pcm, bad crank shaft sensors and bad air pump I replaced all of these things and cleared my cat and now I have a miss fire in cylinder one and my car still doesn’t want ti rev past 4k-5k any ideas ? It’s a 05 rx8 manual if that helps

 

Are there any other codes?

​​​​​​Not revving past 3 is limp mode due to OMP problem which not every code reader can read.
Not revving past 4-5 is clogged cat, bad ignition coils/spark plugs/oil in the intake/intake valves stuck in various open/closed positions. Try to eliminate each of those as the problem?

 

[QUOTE=Loki;4982388]Are there any other codes?

​​​​​it revs past 3k rpm but no the only codes I got were the crank shaft position sensor fixed that and a code for a air pump and I fixed that and went I went to reset the codes I got another code for the misfire on cylinder 1, but I cleared the cat it was clogged but I unclogged it and it a had more power fs but still won’t go really go past 4 to 5 rpm’s, so would it be the miss fire making it not want to go past 4k?

 

Cyl.1 misfire could be bad coils, a usual suspect with misfires.
HOWEVER, bad compression can cause misfires also.
Before sinking any more money into it or just changing any more parts trying to fix it, get a rotary specific compression test.