2005 RX8 GT 6MT
Car: ~435XX miles
New Motor: ~6XX miles
Rebuilt Trans: ~6XX miles
Clutch: Original clutch
Mods: Intake, cat delete race pipe, catback exhaust

So I haven’t taken the car back to the dealer yet, but I'm already having major problems with the new motor... could be the clutch, but I'm pretty sure it's the motor.
When it's cold and you start the car it either dies right away or it stays running til you put it in gear and start tot drive... then it dies. Now I know you have to warm the car up before you drive it, but do I have to warm it up every single time the car itself is cold? I was under the impression that it only needs to be done once in the morning. I started noticing the problem around Sunday night. Actually it wasn't bad til then.
Sunday night... car hadn't been driven for a few hours and went to go get food. Put it in 1st and drove 100 yards perfectly fine. Then after that it started to stutter like it wanted to die... and got "bouncy" like you weren't giving it enough gas. Pulled over, let the car warm up a little and then it drove semi fine.
Monday morning... I needed to move the car at work. Again it hadn't been driven for about 3 hours and moved it. Put it in gear and started driving... it died. Started it back up and let it warm up. Fine after that.
Tuesday (today) morning... Ready to go home in the morning started the car to let it warm up and it died instantly. It revved to about 3/4XXX and instantly died without touching it.
Things I've noticed over the past couple days. In the lower rpms, it feels like it stutters and isn't getting enough fuel or air or something. It's mainly between 25XX and 5XXX rpms. It almost feels like it wants to get up and go, but can't. Also, my wideband gauge reads "---" when I'm about half way down on the gas. It will sometimes read in the 17/18 range, but mainly it reads "---" til you get floor it then it AFR's drop to around 12.X. Last but not least the check engine light blinks more than normal. I have a cat delete race pipe on so it's on all the time, but it never blinked this much when I had the old motor in. It's blinking before the red line mark... like around the 4500/6 area. One thing to note... when you're driving it like an every day driver it has the problem/hesitation... when you floor it it does perfectly fine.
Anyone have any idea?

IDK what could be the matter. Have you checked to see what the CEL is for? Usually when I get a flashing CEL it's for random missfire. I always get since they replaced my motor 15,000 miles ago. If it's hesitating mebe the plugs and wires. Ignition coils might be bad. But IDK. just throwing ideas out there. Check to see if all the plug wires are on. After they did my tranny this past fall one of the plug wires wouldn't fully seat on the plug and pop off and I would have to connect it again. Happened 2 more times till I got new wires.

I was under the impression that you should not re-use the clutch or pressure plate. Especially in your case where you have 40 some thousand on the original ones.

My first thought was coils.

My first thought was that you should have gone with Cool Ranch instead of Spicy Nacho for your magical spinning Dorito machine.

MazdaTom wrote:My first thought was that you should have gone with Cool Ranch instead of Spicy Nacho for your magical spinning Dorito machine.

Nah I prefer JDM yO




So after much thought I'm thinking it's either the fuel pump or fuel filter... then again I could be wrong. Last night as I was cruising around my check engine light was blinking like it has been doing for the past week. I got on it a little and right at 7k it bogs down/stutters and won't go past that. I'm taking it to the dealer today so hopefully something happens.

I am going to agree with Chris and say ignition coils and maybe spark plugs.

Also, if you got a new motor you should follow racing beats break in procedures.

http://www.racingbeat.com/FRmazda4.htm

*DarthRX8* wrote:I am going to agree with Chris and say ignition coils and maybe spark plugs.

Also, if you got a new motor you should follow racing beats break in procedures.

http://www.racingbeat.com/FRmazda4.htm

How critial is it to follow those procedures? I definitely haven't been doing that...

The Korean wrote:How critial is it to follow those procedures? I definitely haven't been doing that...

When I got my new motor I asked the service manager at Lakewood Mazda if there is any special break in that I have to do like when I first got the car for the first 500 miles. They said no. But I did anyways for those first 500.

It wouldn't hurt to do the procedures.

If it is the coills and the dealear replaces them free you should think about ordering BHR's ignition upgrade. If they are gonna charge you just get the ignition upgrade. I beleive the coils are $70 each. The ignition upgrade I think is $395. It's worth it though cause the stock coils will just give out again. I've gone through 3 sets in less than a year. My next purchase will be the ignition upgrade.

I wouldn't always listen to the dealer....

Racing beat has been one of the most knowledgeable rotary experts for many years (Mazda asked them to help build the Furai Concept)!

I bought my RX8 used (13K miles) so I didn't have to do this and I am not sure if the previous owner did, however if I did buy new I would have definitly done this!

All of the break in period stuff aside. It sounds like you need new coils. If you search in the RX8 club under the technical discussion, you will see that many others have had the same problem and when they got new ignition coils and spark plugs the rough acceleration and idle was fixed!

Also make sure your RX8 has the most recent ECU flash (MSP16 I believe, see the link below for all service recalls on the RX8) and starter from Mazda. It is a mandatory recall and will be done for FREE by the stealership.

http://www.finishlineperformance.com/store/pages.php?pageid=11

Good luck!

*DarthRX8* wrote:I wouldn't always listen to the dealer....

Racing beat has been one of the most knowledgeable rotary experts for many years (Mazda asked them to help build the Furai Concept)!

I bought my RX8 used (13K miles) so I didn't have to do this and I am not sure if the previous owner did, however if I did buy new I would have definitly done this!

All of the break in period stuff aside. It sounds like you need new coils. If you search in the RX8 club under the technical discussion, you will see that many others have had the same problem and when they got new ignition coils and spark plugs the rough acceleration and idle was fixed!

Also make sure your RX8 has the most recent ECU flash (MSP16 I believe, see the link below for all service recalls on the RX8) and starter from Mazda. It is a mandatory recall and will be done for FREE by the stealership.

http://www.finishlineperformance.com/store/pages.php?pageid=11

Good luck!

Now that I read the RB guidlines they are pretty much what was said to do when I got the car with the exception that RB has added 500miles on top of it.

I would be surprised if the dealership didn't reflash the ECU with the MSP16 when they did the motor and tranny.

Well took it back to the dealer yesterday and...

I guess there was a loose sensor that was causing most of the problem. Check engine still blinks a little more than normal, but it's not as bad.

I had quite a few codes though...
-A few too lean codes
-Cylinder 2 misfire
-No cats or whatever that code is

Did they say which sensor?

The "Cylinder" 2 missfire is what is throwing the CEL. I have had that problem since my new motor as well. What I learned from asking oin RX8club (That was a scarry thing) Is to basically ignore it. It's nothing just the eccentic shaft position sensor giving a false static signal. Something to do with it not being cleaned before reinstaled in the new motor. One day I'll get to changing it out.

No cats. Bet the car sounds mean.

Greek8 wrote:Did they say which sensor?

The "Cylinder" 2 missfire is what is throwing the CEL. I have had that problem since my new motor as well. What I learned from asking oin RX8club (That was a scarry thing) Is to basically ignore it. It's nothing just the eccentic shaft position sensor giving a false static signal. Something to do with it not being cleaned before reinstaled in the new motor. One day I'll get to changing it out.

No cats. Bet the car sounds mean.

Yes they did... can't remember the name, but it's pretty much on the front of the motor, down low. Does that help?

Hum... I'll keep that in mind then.

Ya, it does... it's hella loud and shoots anywhere from 8 in to 2 foot flames. I need a different race pipe and exhaust though. It's too raspy... it doesn't bug me, but I want a little different sound. It pretty much has the sound of a pissed off weed wacker. I will tell you it has a unique sound and can be heard quite a aways away...

I bet. I remember for about a week I was running the car without an exhaust system and man was it loud with just the cats.

When I did the flywheel we left the cats off and I drove it for about an hour. Man that was really loud. I want to shoot flames. Warranty is up so I might as well go catless now.