2007, manual 6 speed manual trans - it lags power
 

2007 rx8 manual 6-speed stormy blue mica

Hi everyone, Ive read through a few posts...some where helpful. Based upon a few suggestions, Ive replaced the (4) coils, (4) wires, (4)plugs with all new parts...pretty easy work really.

Experiencing Same Problem EVEN AFTER said new parts installed:

The 8 starts fine: Not a quick start/not hard start either. Call it a mild start (2-3 second start-up). Some coughing-sputtering out exhaust past couple weeks experience weather temp changes in WI.

No Engine Check Lights before start. No Engine Check Light when driving. The other day, the temp dropped from 50-70F to 28F... in a few hours, no big deal the car does just fine for WI winters...It sat outside for about 3 hours in 28F (its used to being garaged 50F). But it started right up, it warmed up, and then I casually drove it home.

Drove home 19-24 miles on country roads, a few stop-and-go lights 35-50mph max with No Engine Check Lights present. I could come to a good stop, yet once ready to gradually accelerate, the rpms revved up normally, but the revs needed to stay higher- longer for it to physically increase its speed. As if it had some power/acceleration lag.

Curious, because its 6-speed manual, I question the clutch slipping/not fully release/engage motor to convert power?
- something not fully engaging the rotary power?
- Is there a Clutch Adjustment perhaps I should check?
- what else would cause this when Ive replaced coils, wires, and plugs?

Please HELP.
I was thinking possibly the trans fluid is low(?) - low compression?

Honestly, I have not had anything major/mechanical/ELE go wrong with this 2007 RX8, and have driven it from about 52K miles to 84k without any issues (2.5-3 years).

What else could it be that's causing this lag/lack of acceleration when there's no Engine Check Light present?

Thank you in advance!

Exactly what coils did you replace the old ones with?

If your rpms are not consistent with your speed as in when you accelerate the rpms go up but your speed barely increases your clutch is slipping.

Check your cat for blockage

I used Import Direct OE replacement parts
#43471 for the ignition wire set
#23-0100 for the coils - they all match correctly
NGK 2 Lazer Iridium RE7C-L, 2 RE9B-T

All parts were installed-the car starts fine...no engine check lights....
Still lacks forward power/thrust match rpm revs.

Okay if clutch is slipping, is there an adjustment for that?
I dont abuse this car but I dont drive like an ol/man either.
I also do not ride the clutch and the car has 84k miles.

I drove it to work mildly it was fine. Took it out for lunch and noticed that faint clutch smell.

I did not see a Clutch fluid fill/reservoir under the hood. Is the clutch master and slave fluid shared with the brake master cylinder? What else should I be checking at this point, including the cat for blockage?

I'm afraid there's no adjustment.
You can try putting the car in 3rd and drive off from a stop if it doesn't stall and the rpms go up it might be time for a new clutch.

As to the cat, take the 8 for hard drive then park and look for a red glow in the converter or around the o2 sensor on the cat

okay - will do. Another friend suggested sea foam to clean engine and intake, as it may help to clean the SSV (Secondary Shutter Valve) which could also be stuck. A stuck SSV causes the same power loss, with also has no check engine light ~ So I've read.)

If cat check and sea foam doesnt fix it, I'll then physically check the SSV/perhaps even install the latest version. IF that doesnt fix the problem...then I will have to think its really the clutch.

Im trying to work least money solutions first before clutch. Thanks for helping devise a Plan!

No problem. If you seafoam don't forget to disconnect the cat cuz it will clog it.
you can easily check the ssv if it works properly without taking it out, I'd suggest doing that.

Okay I only did a 1/2 a bottle (8oz) of sea foam spray into throttle body not any vac line. While adding sea foam, a couple minutes into it, I think car went into a little panic mode and CEL came On and started to loose rev...so I stopped sea foam and shut it down for 2 minutes.

When I started the car, it revved normal again and white smoked for only a minute two, then cleared. Since the CEL was still ON...went to autozone for scan. Scan produced: P2112 and 0302 and then grandpa drove it back to work. An hour later, I removed the 15A "room fuse" in the footwell area, started the car, and the CEL was gone.

P2112 - Throttle Actuator - stuck closed
P0302 - Cylinder 2 misfire

Ive already replaced the coils, wires and plugs - so perhaps I'll examine the plugs and clean them tonight after I HWY drive to go through some of this sea foam/gas mix. I'll then change oil and filter in a couple days.

The cat converter - is not hot red anywhere, and exhaust looks clean - not white smoke.

I was told to check the SSV. But I dont know how to do that.
- Do I need a hand pressure pump tool to test the vac line into the SSV?
- how do I accomplish this without removal?
Please assist.

Thank you in advance.

Ok don't forget to reset the memory fully. Put the key to on position and stomp the brake about 20 times within 8 seconds. You should see the oil pressure gauge go right and left if you do it successfully. Take the key out and then start it. You have to clean the plugs for sure. After you do that, then assess the current situation of the 8, as in see if there are check engine lights and see how it drives.

Jon316g has a perfect thread about checking the ssv here's the link

https://www.rx8club.com/series-i-do-...-video-184663/

But If you don't have an engine light pertaining to the ssv I would only check If it cycles and focus on the problems you currently have.

To check if it cycles, simply go for a hard drive to get the car nice and hot, park it and don't turn it off. Open the hood, look at the ssv and tell a buddy to turn off the car. Then you should see the ssv open and close.

helping a fellow out
 

I had the same problem too it might be your omp sensor it is either bitten or torn. A couple of racooons ate my omp sensor wires and it put my car in limp mode(lost of power). once i bought that piece my car was back to normal

Thanks for the reply.
I believe based upon your scenario you would of had an CEL On - is that Correct?

Odd how my rx8 presents no CEL which would indicate anything ELE/sensor/air-vac line...Yesterday, local stop/go acceleration to 10-15 minute on hwy, I have to rev rmps at or above 6K rmps to feel any significant (clutch) thrust. Then faint clutch smell.

- So likely its the clutch since there's no CEL On + smell.
- If it was the SSV or anything ELE or sensor-ed, a CEL code would present itself.

The 2007 RX8 has 87,000 miles on it. This is the first clutch replacement.

Sry about yer racoons

...Now that its been a couple of days Ive notice the clutch slip a little more and faint clutch burnt smell present.

Since there's no CEL ON, everything else is in working order...
I too think its a clutch issue - the RX8 has 87,000 miles and this is the first clutch replacement. 37k more miles than expected-from what Ive read.

It's even fun to drive in WI winter wonderland.

Hi sorry late response, the cel was on. Its still on now i just need to get my car checkouted. The car runs solid atm. good luck man

Yeah looks like your clutch is done. Make sure you get the stock one. Yeah here in Chicago we didn't have snow in a while, where in WI are you?

So if CAT is glowing, even just a little, around the O2 sensor CAT is bad?? I can't see mine glowing when light out after a hard run but in the dark after a hard run, like floored redline shift run up 0 to 115 then pull over as quick as possible in the DARK I can see a mild glow around the rear O2 sensor, normal or bad cat?

Not always but It might be. The best way to verify is to unbolt it and inspect it. For example mine had a slight red glow around the o2 so I took it off shook it and it rattled inside cuz of the broken honey combn

Cat ok??
 

Replaced my O2 sensor today, while under there I unbolted front of CAT to look inside

This looks good to me??

I also then took a large 550 CFM leave blower, blocked off one of the exhaust outlets and hooked leaf blower to the other and blew threw the other backwards through the CAT, only some white dust came out, very little, no pieces of anything. The leaf blower didn't bog or change RPM as usually if you block its outlet its RPM will increase. Felt the air coming out of the front of the CAT and it felt same as leaf blower outlet. Then I took the leaf blower and blew through CAT in correct direction, nothing came out of the exhaust except lots of air. Safe to say its good?

There's a hairline crack on it if you look closely. Mine looked good when looking into it too until I put a cable cam through the o2 hole and saw the insides in crumbles. I honestly think yours is still suspect.

That mark that looks like a crack is something that was on the face of the honey comb that burnt into it. I thought it was a crack too but in looking at it closely with a bright flashlight I don't think its a crack as the honey comb holes around it look normal ?

Did some temps checks after start up. 420F inlet 530F outlet. With my OBD2 connected while running idle was around 850 F, after a 10 mile run up a small mountain at idle was 1220, running hovering around 1350F, after 3 hard 1/4 mile runs was 1481F but cooled back down quickly to 1375, then 1325-135 for the ride home, exhaust smells normal.

Replaced the primary O2 sensor while doing this, I might take the one out in the cat and see what it looks like next

I don't trust those tests. For ex my obd is showing the same temp gutted as it showed prior to gutting it. I took the cat off, put a strong light on one end to see if I could see it on the other end, I did not. Test 1 failed. Shook the whole cat, it rattled just a little bit. Test 2 failed. Finally, took out the cat sensor, slid in a phone spy cam, and that did it. I was surprised how torn up that thing was inside. Test 3 failed. Let me know how it goes.

https://cimg9.ibsrv.net/gimg/www.rx8...72c34175f6.jpgMy cat from outside
https://cimg3.ibsrv.net/gimg/www.rx8...c61d58f4cb.pngMy cat from inside

I'll have to pull out the down stream O2 sensor and stick my inspection camera in there and see what it looks like. What did you end up doing, replacing the CAT ?

I gutted the cat, emissions are two years away so I'm good for now. Now I have peace of mind.

Did it run better after gutting the CAT? Do you get CEL now with it gutted?

Did it change exhaust sound?