Running Rich
03-09-2015, 05:01 PM
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Yes, please be more descriptive. We need to know how you came to that conclusion, and what "rich" is, and when. 10.7 AFR at idle is quite different than 8.3 at full throttle 8,000rpm. Etc.
Giving us OBD2 data to back it up, like what your fuel trims are like when you are seeing the condition, helps a lot too.
Giving us OBD2 data to back it up, like what your fuel trims are like when you are seeing the condition, helps a lot too.
03-09-2015, 05:32 PM
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I can tell by the smell it's giving off. I'm new to this so I don't know how to get readings for you. I'm sure as hell not going to take to the dealership. I have minimal mechanical knowledge, I cleaned my MAF, last night, plan to Sea foam it this weekend 83313 miles, last oil change has them use synthetic, this oil change plan to use reg oil.
I remember the smell from when I raced 4 wheelers. Since this is a 2 stroke engine. I figured that similar smell when my flat track blaster was running rich, would be a good reference.
I remember the smell from when I raced 4 wheelers. Since this is a 2 stroke engine. I figured that similar smell when my flat track blaster was running rich, would be a good reference.
03-09-2015, 05:34 PM
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Ok, so you probably aren't actually running rich. You might be, but the rotary always has a heavier fuel smell than piston engine cars. It's more likely that if you have either a brand new car or something recently smells different that your cat is failing, and letting more raw fuel through.
If you get an OBD2 bluetooth adapter (or wifi if you have an iphone or something without bluetooth) from amazon for a few bucks, you can plug that in and download an OBD2 app for your phone and actually look at the live data to see what your AFR is. It's a useful tool to have anyway, so I still recommend it.
If you get an OBD2 bluetooth adapter (or wifi if you have an iphone or something without bluetooth) from amazon for a few bucks, you can plug that in and download an OBD2 app for your phone and actually look at the live data to see what your AFR is. It's a useful tool to have anyway, so I still recommend it.
03-09-2015, 05:39 PM
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The cat? Center of the car, underneath, middle section of the 3 exhaust pieces.
The ECU has a number of things it can and will do if you are consistently running rich, including a check engine light. However, it is terrible at telling when the cat is failing. So without a CEL and without any further information, a more likely guess is that it's a cat problem, not an AFR problem.
The ECU has a number of things it can and will do if you are consistently running rich, including a check engine light. However, it is terrible at telling when the cat is failing. So without a CEL and without any further information, a more likely guess is that it's a cat problem, not an AFR problem.
03-09-2015, 05:43 PM
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Cool, thanks man. I've noticed a few things lately. When shifting at high RPMs, I can't speed shift, I have to let the RPMs decrease a little before shifting. And every now and then at around 7500 it's almost like stutters, for a split second, then back to normal. I probably need to clean the sock.
03-09-2015, 06:35 PM
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03-09-2015, 07:02 PM
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If you, or the prior owner, has the wrong or old fluid in there, the syncros are usually the first thing to go. Change to Redline MT90, OEM fluid, or Eunos. Don't experiment with other fluids. These are proven and easy to get.
Another thing to check would be clutch engagement. If your clutch line needs to be flushed/bled then the pedal movement might not be moving the pressure plate far enough off othe flywheel.
Another thing to check would be clutch engagement. If your clutch line needs to be flushed/bled then the pedal movement might not be moving the pressure plate far enough off othe flywheel.
03-10-2015, 02:48 AM
#16
Now that I'm at home and not typing on my phone, I'll expand a bit on what I said.
These engines are similar to two-strokes in some ways, similar to four-strokes in other ways, and dissimilar from both in yet other ways. They're similar to two-strokes in that oil is intentionally introduced into the combustion chamber for lubrication. However there's a huge difference in the amount that is introduced. A typical fuel-oil ratio for a two-stroke dirt bike is 30:1. That means for every 30 gallons of gasoline, you burn one gallon of oil. On an RX-8, that would be around two quarts of oil every time you fill up or one quart per 100 miles. I don't know about yours, but my car doesn't burn oil at anywhere near this rate. They're also similar to two-strokes in that the rotors/pistons serve as the intake and exhaust valves rather than having a complex valvetrain.
They're more similar to four-strokes in that the intake and exhaust ports aren't open at the same time (except for some slight overlap) so the cycle is more like that of a four-stroke with a separate intake and exhaust. There's also no secondary compression.
It's dissimilar to either in that the combustion chamber has a completely different shape. Reciprocating engines don't have two spark plugs with different timing in each combustion chamber. They don't have to worry about squish flow or a significantly varying air-fuel ratio in different parts of the combustion chamber.
The moral of the story is, while having some similarities to both, this engine isn't a two-stroke or a four-stroke.
These engines are similar to two-strokes in some ways, similar to four-strokes in other ways, and dissimilar from both in yet other ways. They're similar to two-strokes in that oil is intentionally introduced into the combustion chamber for lubrication. However there's a huge difference in the amount that is introduced. A typical fuel-oil ratio for a two-stroke dirt bike is 30:1. That means for every 30 gallons of gasoline, you burn one gallon of oil. On an RX-8, that would be around two quarts of oil every time you fill up or one quart per 100 miles. I don't know about yours, but my car doesn't burn oil at anywhere near this rate. They're also similar to two-strokes in that the rotors/pistons serve as the intake and exhaust valves rather than having a complex valvetrain.
They're more similar to four-strokes in that the intake and exhaust ports aren't open at the same time (except for some slight overlap) so the cycle is more like that of a four-stroke with a separate intake and exhaust. There's also no secondary compression.
It's dissimilar to either in that the combustion chamber has a completely different shape. Reciprocating engines don't have two spark plugs with different timing in each combustion chamber. They don't have to worry about squish flow or a significantly varying air-fuel ratio in different parts of the combustion chamber.
The moral of the story is, while having some similarities to both, this engine isn't a two-stroke or a four-stroke.
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