Just got the parts for a MS3X
#1
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Per the title, just got the parts to do a MS3X via the trubokitty instructions...
Picking up a set of ITB's this weekend with a plenum, planning on getting that all hooked up and then deciding if I want to turbo them or build a high comp NA; will keep this updated as I go along...
Are there any small "things" I should know about doing a MS3X to my NB1 platform? I think that I will want to go VVT later on, not sure how difficult that is - I was just going to solder the resistor in place on the back and leave it there until I get a new head, but, I'm unsure how that would work with the NB1 ECU connection...
Picking up a set of ITB's this weekend with a plenum, planning on getting that all hooked up and then deciding if I want to turbo them or build a high comp NA; will keep this updated as I go along...
Are there any small "things" I should know about doing a MS3X to my NB1 platform? I think that I will want to go VVT later on, not sure how difficult that is - I was just going to solder the resistor in place on the back and leave it there until I get a new head, but, I'm unsure how that would work with the NB1 ECU connection...
#6
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this will help you: http://www.mellens.net/mazda/mazda_m...999_wiring.pdf
#7
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wire VVT to a spare unsued pin in the engine bay. Connect your vvt solenoid there later. Like the EGR BOOST solenoid valve, or Purge Canister Valve or something. You can use those same connectors to give your vvt solenoid power as well...
this will help you: http://www.mellens.net/mazda/mazda_m...999_wiring.pdf
this will help you: http://www.mellens.net/mazda/mazda_m...999_wiring.pdf
I could just buy a random 4 pin automotive connector as well.
Is the 12V that goes to the EGR from the ECU, or otherwise supplied?
#9
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just finished putting it together and wiring up the harness, have it powered off the car and I'm flashing it right now... Going to try and get it running with the stock intake tomorrow, then when my TPS & filters come on Friday, drop in the AE101 ITB's with the T3 manifold & stacks.
Thanks for the walkthrough on trubokitty
Thanks for the walkthrough on trubokitty
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#10
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Fuel pump primes, engine cranks, all sparks tested to be good.
Only issue is, I'm not seeing any RPM when cranking!
I have the jumpers per your instructions, and I have triple checked the three trimpots and even messed around with the 7.5 turn one a bit...
However - I just noticed, https://trubokitty.com/assets/images/ms3x_expander.png shows a ground connection from X - 32 to the main 37 pin d sub connector.
I didn't do that - I'm assuming that that would cause this issue? Can anyone explain what is meant by this, hopefully with a picture? Thanks much!
Only issue is, I'm not seeing any RPM when cranking!
I have the jumpers per your instructions, and I have triple checked the three trimpots and even messed around with the 7.5 turn one a bit...
However - I just noticed, https://trubokitty.com/assets/images/ms3x_expander.png shows a ground connection from X - 32 to the main 37 pin d sub connector.
I didn't do that - I'm assuming that that would cause this issue? Can anyone explain what is meant by this, hopefully with a picture? Thanks much!
#11
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do a composite log so we can see if it's the crank or cam sensor that's not inputting. (diagnostics tab, save to file, crank for a good 15-20 sec to get a reading, go WOT when you crank so no fuel is injected)
#12
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Odd! After cranking it for 15-20 seconds, I did get a very short signal...
I'm thinking this means its probably the VR trimpots? Is there a better way to do it than counting turns? The "clutch" on these don't click so I don't know when it is all the way left, I've just been spinning it a ton, getting it vertically aligned and counting half turns... I was seeing that another way is to adjust for minimal voltage off of the top end (one facing the center of the board) of R54 next to the trimpot, using some kind of a ground as the negative. Is that true?
I'm thinking this means its probably the VR trimpots? Is there a better way to do it than counting turns? The "clutch" on these don't click so I don't know when it is all the way left, I've just been spinning it a ton, getting it vertically aligned and counting half turns... I was seeing that another way is to adjust for minimal voltage off of the top end (one facing the center of the board) of R54 next to the trimpot, using some kind of a ground as the negative. Is that true?
#13
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looks like you were getting the cam signal, but not the crank (I had to look at the log in excel here).
For NBs, I tend to just spin the R56 exactly 8 turns CW (resets at 12 turns CCW). and R11 4 turns CW, with R32 backed out completely (at least 6 full turns CCW).
Whenever I'd try setting these with specific voltages, I kept getting reports of issues.
not following this. pin 32 of the expander is the Cam Sensor Input.
For NBs, I tend to just spin the R56 exactly 8 turns CW (resets at 12 turns CCW). and R11 4 turns CW, with R32 backed out completely (at least 6 full turns CCW).
Whenever I'd try setting these with specific voltages, I kept getting reports of issues.
However - I just noticed, https://trubokitty.com/assets/images/ms3x_expander.png shows a ground connection from X - 32 to the main 37 pin d sub connector.
#19
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the 1k resistor on r13. you need to cut it out from the hole and it needs to only connect down to the other resistor you have it bridged with.
the hole on the far side of that image is 5v. the resistor below is part of the crank signal input circuit. we just use that for a 5v pullup, to power the signal, through that 1k resistor.
youre also missing c31.
everything else seems good. the harness appears to have everything in the right spot.
edit; looking again it seems the pullup is okay?
the hole on the far side of that image is 5v. the resistor below is part of the crank signal input circuit. we just use that for a 5v pullup, to power the signal, through that 1k resistor.
youre also missing c31.
everything else seems good. the harness appears to have everything in the right spot.
edit; looking again it seems the pullup is okay?