Car took a crap at the track, fuel issues? datalog inside
#43
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OK, I just went out and did this:
Using a long screwdriver as my "stethescope", I am 90% certain that injectors 2 & 4 are NOT clicking when I manually spin the CAS by hand. It is hard to tell, because the clicking of a nearby injector transfers through the fuel rail to the others, but like I said, I'm 90% certain - there was a difference in the volume from 1&3 (louder click) than when I listened to 2&4 (probably just the noise from 1&3 which are working.
Sounds like this could be the culprit?
My buddy with a miata is at a holiday party right now, but will try to swap in his CAS and find out. If the CAS is not it, what else could it be?
Sounds like this could be the culprit?
My buddy with a miata is at a holiday party right now, but will try to swap in his CAS and find out. If the CAS is not it, what else could it be?
Last edited by ThePass; 12-16-2011 at 10:53 PM.
#45
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The CAS is an optocoupler. So it could "slowly" die on you. You run a Megasquirt, right? Are you able to view the inputs of the CAS in the Tunerstudio diagnostics menu? That way you can check what's comming in.
You can also check the CAS by checking if ot goes to 0 Volts on the triggerwires. It should switch between 12 or 5 volts and 0 volts. You can turn it slowly by hand. Is the CAS clean inside? You can open it. It should be dry and there should not be any oil in there.
You can also check the CAS by checking if ot goes to 0 Volts on the triggerwires. It should switch between 12 or 5 volts and 0 volts. You can turn it slowly by hand. Is the CAS clean inside? You can open it. It should be dry and there should not be any oil in there.
#46
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Swapped the CAS with a working one. No change.
So, I had my buddy listen to the injectors with a stethoscope while I manually spun the CAS to verify that I wasn't hearing things - he confirmed that 2 & 4 weren't clicking.
We decided to swap in my OEM ECU instead of the Megasquirt. Guess what? HALLELUJAH! Even running without an o2 sensor and on NB injectors and a Walbro 255, it runs smoothly on the OEM ECU - the AFRs are a little off, but it is just fine.
So... firmware? What are the possible culprits within the Megasquirt? I could try to reload the firmware and if that doesn't do it maybe I need to send it in to DIYPNP...
-Ryan
So, I had my buddy listen to the injectors with a stethoscope while I manually spun the CAS to verify that I wasn't hearing things - he confirmed that 2 & 4 weren't clicking.
We decided to swap in my OEM ECU instead of the Megasquirt. Guess what? HALLELUJAH! Even running without an o2 sensor and on NB injectors and a Walbro 255, it runs smoothly on the OEM ECU - the AFRs are a little off, but it is just fine.
So... firmware? What are the possible culprits within the Megasquirt? I could try to reload the firmware and if that doesn't do it maybe I need to send it in to DIYPNP...
-Ryan
#48
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Swapped the CAS with a working one. No change.
So, I had my buddy listen to the injectors with a stethoscope while I manually spun the CAS to verify that I wasn't hearing things - he confirmed that 2 & 4 weren't clicking.
We decided to swap in my OEM ECU instead of the Megasquirt. Guess what? HALLELUJAH! Even running without an o2 sensor and on NB injectors and a Walbro 255, it runs smoothly on the OEM ECU - the AFRs are a little off, but it is just fine.
So... firmware? What are the possible culprits within the Megasquirt? I could try to reload the firmware and if that doesn't do it maybe I need to send it in to DIYPNP...
-Ryan
So, I had my buddy listen to the injectors with a stethoscope while I manually spun the CAS to verify that I wasn't hearing things - he confirmed that 2 & 4 weren't clicking.
We decided to swap in my OEM ECU instead of the Megasquirt. Guess what? HALLELUJAH! Even running without an o2 sensor and on NB injectors and a Walbro 255, it runs smoothly on the OEM ECU - the AFRs are a little off, but it is just fine.
So... firmware? What are the possible culprits within the Megasquirt? I could try to reload the firmware and if that doesn't do it maybe I need to send it in to DIYPNP...
-Ryan
That is what I feel it will need, interestingly you could see how the car was running mega rich and causing the sensor to read "lean" even though the opposite was occurring.
#49
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Yeah I am incredibly relieved to have narrowed it down to one component. Even though it's the MS, which could suck if reloading the firmware doesn't fix it, I'm glad to have figured out what it is. I don't mind stuff breaking. I can repair/replace whatever it is. It's the whole replacing nearly everything in the fuel and ignition systems and still not knowing what it is part that was seriously eating at me
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#50
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Yeah I am incredibly relieved to have narrowed it down to one component. Even though it's the MS, which could suck if reloading the firmware doesn't fix it, I'm glad to have figured out what it is. I don't mind stuff breaking. I can repair/replace whatever it is. It's the whole replacing nearly everything in the fuel and ignition systems and still not knowing what it is part that was seriously eating at me ![](https://www.miataturbo.net/images/smilies/smile.gif)
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#55
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How can I accurately test if the injectordriver is working correctly on my DIYPNP?
#57
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MS2/Extra - Output Test
Tested each injector which seemed to work. Each one tested similarly with the settings recommended on the msextra link above.
I also installed my new fuel pump, but it didn't change a thing.
Next step is firmware upgrade from 3.1.1 to 3.3.1
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