misfire after engine running fine for 20 min
07-07-2011, 01:48 PM
#26
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Well.............for one, the gauge in the car really only has three positions.....that's why we call it a dummy gauge. "Cool, normal, and Aaaaaw ****, too late" mode.
The value off the PCM should be correct and that's the one I would believe. If only 70 degrees, then I would see why it might run rich, but again I'm not expert. I have to doubt the 70 degrees as well......that's mighty low! Your not talking Celsius are you?
If it was truly not getting to temp............it should throw a code for that(P0126), which you have not mentioned.............so not really sure it's the temp sensor either. Car needs to see ~170F within two drive cycles or it will throw that code.
I did just go through somewhat of a similar issue on my daughters 3 in that the thermostat was stuck open, but even stuck open................it got 160F consistently, but threw the P0126 code as it never reached 170F.
I'll try some searches(you should as well) on the temperature sensor (ECT) and see what comes up.
For the sake of argument............I know your frustrated, but you really expect us to fix your car over the internet? We are trying to help, but attitude won't get us anywhere either.
To be honest, let's hope it's not your PCM......and don't freak out, it's way too early to even think that it might be.
The value off the PCM should be correct and that's the one I would believe. If only 70 degrees, then I would see why it might run rich, but again I'm not expert. I have to doubt the 70 degrees as well......that's mighty low! Your not talking Celsius are you?
If it was truly not getting to temp............it should throw a code for that(P0126), which you have not mentioned.............so not really sure it's the temp sensor either. Car needs to see ~170F within two drive cycles or it will throw that code.
I did just go through somewhat of a similar issue on my daughters 3 in that the thermostat was stuck open, but even stuck open................it got 160F consistently, but threw the P0126 code as it never reached 170F.
I'll try some searches(you should as well) on the temperature sensor (ECT) and see what comes up.
For the sake of argument............I know your frustrated, but you really expect us to fix your car over the internet? We are trying to help, but attitude won't get us anywhere either.
To be honest, let's hope it's not your PCM......and don't freak out, it's way too early to even think that it might be.
Last edited by Mazurfer; 07-07-2011 at 02:27 PM.
07-07-2011, 08:07 PM
#27
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Well.............for one, the gauge in the car really only has three positions.....that's why we call it a dummy gauge. "Cool, normal, and Aaaaaw ****, too late" mode.
The value off the PCM should be correct and that's the one I would believe. If only 70 degrees, then I would see why it might run rich, but again I'm not expert. I have to doubt the 70 degrees as well......that's mighty low! Your not talking Celsius are you?
If it was truly not getting to temp............it should throw a code for that(P0126), which you have not mentioned.............so not really sure it's the temp sensor either. Car needs to see ~170F within two drive cycles or it will throw that code.
I did just go through somewhat of a similar issue on my daughters 3 in that the thermostat was stuck open, but even stuck open................it got 160F consistently, but threw the P0126 code as it never reached 170F.
I'll try some searches(you should as well) on the temperature sensor (ECT) and see what comes up.
For the sake of argument............I know your frustrated, but you really expect us to fix your car over the internet? We are trying to help, but attitude won't get us anywhere either.
To be honest, let's hope it's not your PCM......and don't freak out, it's way too early to even think that it might be.
The value off the PCM should be correct and that's the one I would believe. If only 70 degrees, then I would see why it might run rich, but again I'm not expert. I have to doubt the 70 degrees as well......that's mighty low! Your not talking Celsius are you?
If it was truly not getting to temp............it should throw a code for that(P0126), which you have not mentioned.............so not really sure it's the temp sensor either. Car needs to see ~170F within two drive cycles or it will throw that code.
I did just go through somewhat of a similar issue on my daughters 3 in that the thermostat was stuck open, but even stuck open................it got 160F consistently, but threw the P0126 code as it never reached 170F.
I'll try some searches(you should as well) on the temperature sensor (ECT) and see what comes up.
For the sake of argument............I know your frustrated, but you really expect us to fix your car over the internet? We are trying to help, but attitude won't get us anywhere either.
To be honest, let's hope it's not your PCM......and don't freak out, it's way too early to even think that it might be.
First off, thanks for your reply. I have just seen so many issues on here with helpful posted replies, i kinda feel left out. My thinking is like yours, i feel like it should have thrown a code, but it didnt....
I searched the site high and low for anything on the ECT, and found nearly nothing which leads me to believe its not common for it to take a dump.
Funny thing is the mechanic let me see the reading on the car but i didnt look to see if it was celcius or degrees. But both mechanics said it was only getting to 70 or so degrees but before i used my actron scanner which i understand is cheap but showed the temp just as it should be.... usually between 190-205 degrees, he swore his 10,000.00 snap on scanner was reading the right temp.
The mechanic told me he had most likely thought my problems were electrically related, possibly the pcm...
Im going to get it fri evening and see what my scanner says, then prepare to drop it off at the dealer if i cant find anything.
I did call the dealer and they said it needed to be reflased, and was covered under warranty.... so im going to go from there.
Again thank you for the support!
07-07-2011, 10:07 PM
#28
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Reflash might just solve your problem(s). Good luck.
It would appear that your so-called cheapo scanner gave you the right number and hence no code for being too low.
That's a good thing! This also matches what your "dummy gauge" was telling you.
Not sure what the "F" they(the mechanics) were doing?
If the code reader used isn't CANBUS compatible it usual won't even connect or give a communication code.
70C = ~158F, so if they were reading Celsius, then it would in fact be a little low......but only if the car was warmed up.
Given this info of what you have now stated, I think I would not go back to that mechanic.
I searched as well and I did find one small thread were someone was going to replace the ECT but it wasn't clear why. Then I saw a few that sort of mirrored what I said about the thermostat staying open, so those were changed. I think this whole thing doesn't even apply anymore.
Now, I gotta go back and read the whole thread to see where we are at in terms of what the car is doing/not doing given I think the whole temp thing was a ruze.
FYI...............did they(the dealer) mention what flash?
Oh............Ask them if your car has had MSP16. I know you may not have lack of power, but you might want to verify you've had this done or not. (See attached)
Make sure they run it long enough to see it sputter or misfire.
It's possible that even though the coils are new that you have a bad one I suppose.
BTW................put at least some form of your location in your profile. If anyone is local to you, they might be willing to help out.
Beer is the normal currency!
It would appear that your so-called cheapo scanner gave you the right number and hence no code for being too low.
That's a good thing! This also matches what your "dummy gauge" was telling you.
Not sure what the "F" they(the mechanics) were doing?
If the code reader used isn't CANBUS compatible it usual won't even connect or give a communication code.
70C = ~158F, so if they were reading Celsius, then it would in fact be a little low......but only if the car was warmed up.
Given this info of what you have now stated, I think I would not go back to that mechanic.
I searched as well and I did find one small thread were someone was going to replace the ECT but it wasn't clear why. Then I saw a few that sort of mirrored what I said about the thermostat staying open, so those were changed. I think this whole thing doesn't even apply anymore.
Now, I gotta go back and read the whole thread to see where we are at in terms of what the car is doing/not doing given I think the whole temp thing was a ruze.
FYI...............did they(the dealer) mention what flash?
Oh............Ask them if your car has had MSP16. I know you may not have lack of power, but you might want to verify you've had this done or not. (See attached)
Make sure they run it long enough to see it sputter or misfire.
It's possible that even though the coils are new that you have a bad one I suppose.
BTW................put at least some form of your location in your profile. If anyone is local to you, they might be willing to help out.
Beer is the normal currency!
Last edited by Mazurfer; 07-07-2011 at 10:20 PM.
07-08-2011, 06:39 PM
#29
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Reflash might just solve your problem(s). Good luck.
It would appear that your so-called cheapo scanner gave you the right number and hence no code for being too low.
That's a good thing! This also matches what your "dummy gauge" was telling you.
Not sure what the "F" they(the mechanics) were doing?
If the code reader used isn't CANBUS compatible it usual won't even connect or give a communication code.
70C = ~158F, so if they were reading Celsius, then it would in fact be a little low......but only if the car was warmed up.
Given this info of what you have now stated, I think I would not go back to that mechanic.
I searched as well and I did find one small thread were someone was going to replace the ECT but it wasn't clear why. Then I saw a few that sort of mirrored what I said about the thermostat staying open, so those were changed. I think this whole thing doesn't even apply anymore.
Now, I gotta go back and read the whole thread to see where we are at in terms of what the car is doing/not doing given I think the whole temp thing was a ruze.
FYI...............did they(the dealer) mention what flash?
Oh............Ask them if your car has had MSP16. I know you may not have lack of power, but you might want to verify you've had this done or not. (See attached)
Make sure they run it long enough to see it sputter or misfire.
It's possible that even though the coils are new that you have a bad one I suppose.
BTW................put at least some form of your location in your profile. If anyone is local to you, they might be willing to help out.
Beer is the normal currency!
It would appear that your so-called cheapo scanner gave you the right number and hence no code for being too low.
That's a good thing! This also matches what your "dummy gauge" was telling you.
Not sure what the "F" they(the mechanics) were doing?
If the code reader used isn't CANBUS compatible it usual won't even connect or give a communication code.
70C = ~158F, so if they were reading Celsius, then it would in fact be a little low......but only if the car was warmed up.
Given this info of what you have now stated, I think I would not go back to that mechanic.
I searched as well and I did find one small thread were someone was going to replace the ECT but it wasn't clear why. Then I saw a few that sort of mirrored what I said about the thermostat staying open, so those were changed. I think this whole thing doesn't even apply anymore.
Now, I gotta go back and read the whole thread to see where we are at in terms of what the car is doing/not doing given I think the whole temp thing was a ruze.
FYI...............did they(the dealer) mention what flash?
Oh............Ask them if your car has had MSP16. I know you may not have lack of power, but you might want to verify you've had this done or not. (See attached)
Make sure they run it long enough to see it sputter or misfire.
It's possible that even though the coils are new that you have a bad one I suppose.
BTW................put at least some form of your location in your profile. If anyone is local to you, they might be willing to help out.
Beer is the normal currency!
The dealer did mention the flash but is was not installed in my car when the reman engine was put in 60 days ago.
As far as the temp goes, it seems the ingoing temp is around 114 degrees, outgoing is around 180-190. So im not sure if the thermostat is stuck open or not? I would think if it was both temps would be close to the same.... not sure... Ill check it though and see what happens.
I also got the p0171 system to lean code on the way home, with what sounded like a backfire.... When i start the car from cold, it smokes a dark color like its to rich, then leans out... all while i can hear my fuel pump running at full speed.
I dont know if whats going on with my car would be labeled as lack of power but once its run for around 10 miles it starts acting up, sputtering and choking when i push the gas pedal....
07-11-2011, 04:17 PM
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I gave up. Its at the stealership now. I looked around the shop while i was there, there were 2 warranty engine installs going on with rx8's, one was modified, huge tires, aftermarket exhaust.... Along with at least five other rx8's not including mine waiting on work. I'm not looking forward to that call.
07-11-2011, 09:12 PM
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Check out this thread about my car https://www.rx8club.com/series-i-trouble-shooting-95/power-loss-about-7k-sputtering-no-cels-no-other-vital-signs-219208/
The symptoms sounds similiar to ours.
Other causes are less likely to produce these symptoms randomly and after a few runs.
Fuel pressure gauge will not show you much if you are not pushing the car at high load.
My car was hooked up to a pressure gauge and monitored while on the dyno. The pressure stayed at 3.5 - 4 bar on the first few runs till it dropped to 2 bar on the last run.
The symptoms sounds similiar to ours.
Other causes are less likely to produce these symptoms randomly and after a few runs.
Fuel pressure gauge will not show you much if you are not pushing the car at high load.
My car was hooked up to a pressure gauge and monitored while on the dyno. The pressure stayed at 3.5 - 4 bar on the first few runs till it dropped to 2 bar on the last run.
Last edited by Xeqouz; 07-11-2011 at 09:23 PM.
07-12-2011, 04:56 PM
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Check out this thread about my car https://www.rx8club.com/showthread.php?t=219208
The symptoms sounds similiar to ours.
Other causes are less likely to produce these symptoms randomly and after a few runs.
Fuel pressure gauge will not show you much if you are not pushing the car at high load.
My car was hooked up to a pressure gauge and monitored while on the dyno. The pressure stayed at 3.5 - 4 bar on the first few runs till it dropped to 2 bar on the last run.
The symptoms sounds similiar to ours.
Other causes are less likely to produce these symptoms randomly and after a few runs.
Fuel pressure gauge will not show you much if you are not pushing the car at high load.
My car was hooked up to a pressure gauge and monitored while on the dyno. The pressure stayed at 3.5 - 4 bar on the first few runs till it dropped to 2 bar on the last run.
07-13-2011, 02:04 AM
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Maybe you should trust your mechanics instincts a little more?
I had a similar problem recently.
After new coils, leads and plugs, the problem still wasn't resolved.
Diagnostic codes all coming up clear.
I borrowed a friends scanner and did a snapshot of the ecu/pcm.
I then printed it out and read through the displayed values for each sensor and settings.
When I got to the ECT it was showing that it was requesting a voltage of 134V...Huh?
OK, I thought I'd get a sensor as they should be cheap and an easy thing to do.
I'm in the UK and a local Mazda dealership wanted 55 pound plus tax.
Did a bit of research and found it's a fairly generic sensor that comes in a multitude of cars.
Got one from an aftermarket parts supplier for 12 pounds all in.
Spent 25 minutes skinning my knuckles getting the old one out. Slipped the new one in.
Issues sorted, car runs sweet as a nut.
A little bit of Internet searching shows the ECT to be quite a common failure.
It then supplies the wrong values to the PCM/ECU and consequently the car fuels incorrectly.
Trust me, for a few dollars it's worth a try.
If you can get someone with the right software and scanner the RX8 is one of a smaller number of vehicles that supports decent diagnostic information from the ECU via an OBD reader.
Good luck...
I had a similar problem recently.
After new coils, leads and plugs, the problem still wasn't resolved.
Diagnostic codes all coming up clear.
I borrowed a friends scanner and did a snapshot of the ecu/pcm.
I then printed it out and read through the displayed values for each sensor and settings.
When I got to the ECT it was showing that it was requesting a voltage of 134V...Huh?
OK, I thought I'd get a sensor as they should be cheap and an easy thing to do.
I'm in the UK and a local Mazda dealership wanted 55 pound plus tax.
Did a bit of research and found it's a fairly generic sensor that comes in a multitude of cars.
Got one from an aftermarket parts supplier for 12 pounds all in.
Spent 25 minutes skinning my knuckles getting the old one out. Slipped the new one in.
Issues sorted, car runs sweet as a nut.
A little bit of Internet searching shows the ECT to be quite a common failure.
It then supplies the wrong values to the PCM/ECU and consequently the car fuels incorrectly.
Trust me, for a few dollars it's worth a try.
If you can get someone with the right software and scanner the RX8 is one of a smaller number of vehicles that supports decent diagnostic information from the ECU via an OBD reader.
Good luck...
Last edited by lippydave; 07-13-2011 at 02:07 AM.
07-13-2011, 05:07 PM
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Maybe you should trust your mechanics instincts a little more?
I had a similar problem recently.
After new coils, leads and plugs, the problem still wasn't resolved.
Diagnostic codes all coming up clear.
I borrowed a friends scanner and did a snapshot of the ecu/pcm.
I then printed it out and read through the displayed values for each sensor and settings.
When I got to the ECT it was showing that it was requesting a voltage of 134V...Huh?
OK, I thought I'd get a sensor as they should be cheap and an easy thing to do.
I'm in the UK and a local Mazda dealership wanted 55 pound plus tax.
Did a bit of research and found it's a fairly generic sensor that comes in a multitude of cars.
Got one from an aftermarket parts supplier for 12 pounds all in.
Spent 25 minutes skinning my knuckles getting the old one out. Slipped the new one in.
Issues sorted, car runs sweet as a nut.
A little bit of Internet searching shows the ECT to be quite a common failure.
It then supplies the wrong values to the PCM/ECU and consequently the car fuels incorrectly.
Trust me, for a few dollars it's worth a try.
If you can get someone with the right software and scanner the RX8 is one of a smaller number of vehicles that supports decent diagnostic information from the ECU via an OBD reader.
Good luck...
I had a similar problem recently.
After new coils, leads and plugs, the problem still wasn't resolved.
Diagnostic codes all coming up clear.
I borrowed a friends scanner and did a snapshot of the ecu/pcm.
I then printed it out and read through the displayed values for each sensor and settings.
When I got to the ECT it was showing that it was requesting a voltage of 134V...Huh?
OK, I thought I'd get a sensor as they should be cheap and an easy thing to do.
I'm in the UK and a local Mazda dealership wanted 55 pound plus tax.
Did a bit of research and found it's a fairly generic sensor that comes in a multitude of cars.
Got one from an aftermarket parts supplier for 12 pounds all in.
Spent 25 minutes skinning my knuckles getting the old one out. Slipped the new one in.
Issues sorted, car runs sweet as a nut.
A little bit of Internet searching shows the ECT to be quite a common failure.
It then supplies the wrong values to the PCM/ECU and consequently the car fuels incorrectly.
Trust me, for a few dollars it's worth a try.
If you can get someone with the right software and scanner the RX8 is one of a smaller number of vehicles that supports decent diagnostic information from the ECU via an OBD reader.
Good luck...
07-14-2011, 12:24 AM
#38
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My gauge read ok.
All the diagnostics (dtc codes) read ok too.
It was only by interrogating the pcm/ecu that I found the odd voltage requirement of the ect.
For the UK equivalent of 20 bucks and 20 mins to fit, (it's a bit awkward to get at), it's a no brainer.....
I fitted an intermotor part #55123
Check out the online intermotor catalogue at www.intermotor.co.uk
There are 5 pages of vehicle that use this sensor and the catalogue gives you cross-references to other brand part #'s, so should be easy to find one local to you....
07-14-2011, 06:26 PM
#39
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Nope!
My gauge read ok.
All the diagnostics (dtc codes) read ok too.
It was only by interrogating the pcm/ecu that I found the odd voltage requirement of the ect.
For the UK equivalent of 20 bucks and 20 mins to fit, (it's a bit awkward to get at), it's a no brainer.....
I fitted an intermotor part #55123
Check out the online intermotor catalogue at www.intermotor.co.uk
There are 5 pages of vehicle that use this sensor and the catalogue gives you cross-references to other brand part #'s, so should be easy to find one local to you....
My gauge read ok.
All the diagnostics (dtc codes) read ok too.
It was only by interrogating the pcm/ecu that I found the odd voltage requirement of the ect.
For the UK equivalent of 20 bucks and 20 mins to fit, (it's a bit awkward to get at), it's a no brainer.....
I fitted an intermotor part #55123
Check out the online intermotor catalogue at www.intermotor.co.uk
There are 5 pages of vehicle that use this sensor and the catalogue gives you cross-references to other brand part #'s, so should be easy to find one local to you....
07-16-2011, 01:06 PM
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Ok so I just bought a an 2004 rx8 thursday. It looks great and ran great. But friday morning i woke up to take it to get smoged and the check engine light started blinking. I was close to the mazda dealership so i took it there, but by the time i got there there was smoke coming out of the hood. Any ideas of what it is? I really like the car and i wanna keep it.
07-17-2011, 07:20 AM
#41
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^.............. 
how are we supposed to know?
It could be 1,000 things.
You didn't give us nearly enough info to even come close to making any sort of diagnosis.
At this point, you need to ask the dealer exactly what codes it was throwing and let us know.
What color was the smoke?
Was it really smoke and not steam?
Was there any smell to it?
How was your coolant level?
How did it drive on the way to the dealer?
What's the maintainance history of the car?
Did you have it checked out before buying?
Shall I go on or do you get the picture now?
how are we supposed to know?It could be 1,000 things.
You didn't give us nearly enough info to even come close to making any sort of diagnosis.
At this point, you need to ask the dealer exactly what codes it was throwing and let us know.
What color was the smoke?
Was it really smoke and not steam?
Was there any smell to it?
How was your coolant level?
How did it drive on the way to the dealer?
What's the maintainance history of the car?
Did you have it checked out before buying?
Shall I go on or do you get the picture now?
07-17-2011, 09:00 AM
#42
^.............. how are we supposed to know?
It could be 1,000 things.
You didn't give us nearly enough info to even come close to making any sort of diagnosis.
At this point, you need to ask the dealer exactly what codes it was throwing and let us know.
What color was the smoke?
Was it really smoke and not steam?
Was there any smell to it?
How was your coolant level?
How did it drive on the way to the dealer?
What's the maintainance history of the car?
Did you have it checked out before buying?
Shall I go on or do you get the picture now?
how are we supposed to know?It could be 1,000 things.
You didn't give us nearly enough info to even come close to making any sort of diagnosis.
At this point, you need to ask the dealer exactly what codes it was throwing and let us know.
What color was the smoke?
Was it really smoke and not steam?
Was there any smell to it?
How was your coolant level?
How did it drive on the way to the dealer?
What's the maintainance history of the car?
Did you have it checked out before buying?
Shall I go on or do you get the picture now?
Maz .... maybe too much posting today .... just step away from the computer .... put the mouse down
Grab whiskey, sit down outside, breath fresh air
07-17-2011, 10:05 AM
#43
Rockie Mountain Newbie
Ok so I just bought a an 2004 rx8 thursday. It looks great and ran great. But friday morning i woke up to take it to get smoged and the check engine light started blinking. I was close to the mazda dealership so i took it there, but by the time i got there there was smoke coming out of the hood. Any ideas of what it is? I really like the car and i wanna keep it.
Typically a misfire, which usually means you need coils, wires and plugs, unless there's an internal engine issue, like a coolant leak into the rotor housing, or a failed internal engine seal, allowing compression to escape.
BC.
08-03-2011, 02:41 PM
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Just got it back from the dealer monday. Turns out it was a defective fuel pump. Well they said it was a fuel pump, but i know it was the assembly because i replaced the pump in the assembly with a walbro pump and it did the same thing.... Does anyone know if its a common issue for the fuel pressure regulator to fail in the fuel pump assembly? This explains why my fuel pump was always running in high mode- it was trying to maintain fuel pressure because the regulator failed..... sheesh. Glad its fixed....
Thanks to everyone who made and effort to help. Now you guys can go look in the for sale section of for all the good, used parts for sale i replaced whilst trying to fix my car blindly.
Thanks to everyone who made and effort to help. Now you guys can go look in the for sale section of for all the good, used parts for sale i replaced whilst trying to fix my car blindly.
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