ms3x doesn't start car anymore
#1
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Hello! I've been looking around everywhere for informations and stuffs and I'm bet the Brain is getting sick of me bothering him
haha, also, it can't hurt to have more thinkers helping out....
I have ms3x, it has worked fine and started my car for the latter half of last year, and she fired right up and drove after sitting all winter! woot!
...next thing i know? no start, apparently has no-spark. i hadn't changed anything about the tune though. my mechanic plugged in the oem ecu and it fired right up everytime so he tried to tell me there's a problem with the ms ecu. now i got it home and plugged the ms3x back in, no start a few times, started and ran really awful for a few seconds before dying a few times, and back to no start.
billr from msextra tells me (having looked at one of my .msl files) that i "clearly have a tach-in problem" ... idk what that means!
i can post my msl's and csv's if you'd like?
on a sidenote: i also saw on diyautotune that you can use ms as a piggyback and have the stock ecu handle startup and ignition, and just use the ve fuel autotune to have an OK running vehicle? this would be an ideal scenario for me ...i'm not trying to be a race car owner here, just want to drive my car around. my ultimate goal is to have the piggyback effect without having both ecu's hooked up - the stock ecu starts her and keeps her running GREAT! but sadly keeps my feul running super-duper rich while cruising/idling and super-duper thin under boost...
help please?
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I have ms3x, it has worked fine and started my car for the latter half of last year, and she fired right up and drove after sitting all winter! woot!
...next thing i know? no start, apparently has no-spark. i hadn't changed anything about the tune though. my mechanic plugged in the oem ecu and it fired right up everytime so he tried to tell me there's a problem with the ms ecu. now i got it home and plugged the ms3x back in, no start a few times, started and ran really awful for a few seconds before dying a few times, and back to no start.
billr from msextra tells me (having looked at one of my .msl files) that i "clearly have a tach-in problem" ... idk what that means!
i can post my msl's and csv's if you'd like?
on a sidenote: i also saw on diyautotune that you can use ms as a piggyback and have the stock ecu handle startup and ignition, and just use the ve fuel autotune to have an OK running vehicle? this would be an ideal scenario for me ...i'm not trying to be a race car owner here, just want to drive my car around. my ultimate goal is to have the piggyback effect without having both ecu's hooked up - the stock ecu starts her and keeps her running GREAT! but sadly keeps my feul running super-duper rich while cruising/idling and super-duper thin under boost...
help please?
#5
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where does the tach in come from?
having read "you should be able to share the CMP, CKP, CAS signals with the stock ecu to get your TACH signal to trigger the MegaSquirt so you can take control of the fuel injection and leave ignition control to the stock ECU for now...for fuel only control you just need to wire up the IAT, CLT, WB02 and make sure you're getting a good TACH signal"
it makes me think that the TACH signal comes from the CMP CKP and CAS as a collective unit? :\
having read "you should be able to share the CMP, CKP, CAS signals with the stock ecu to get your TACH signal to trigger the MegaSquirt so you can take control of the fuel injection and leave ignition control to the stock ECU for now...for fuel only control you just need to wire up the IAT, CLT, WB02 and make sure you're getting a good TACH signal"
it makes me think that the TACH signal comes from the CMP CKP and CAS as a collective unit? :\
#6
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i just found the "compare tune" thing and compared my current tune to one of my restoration points from march, and one from october of last year - it appears as though my crank advance has been changed from 15 degrees to 10 degrees, would this change be enough to be screwing me up?? i can't get to my car to check it now... unfortunately :\
#7
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Try this first:
You need to open the ECU and readjust the Crank and Cam VR conditioners.
First you'll need to slide the mainboard out of the case. Remove the two serial port studsfrom the USB side of the case. IIRC they are 3/16".
Remove the 4 screws on the opposite end-plate of the case and you can now slideit out from the dual db37 side.
You should be looking at a green expander board and a white daughter-boardconnected by two ribbons.
On the green expander board, lift the top ribbon to expose the two adjusting pots. They are gray cubes with little brass screws on them. Turn them both CCW 10 times. Then on the top one, R11, turn it CW 3 times.
Now remove the studs from the top db37 holding the green expander inplace; kinda of fold it up out of the way for access.
There are two more pots you can adjust here for the crank signal on the mainboard. Turn them both back 12 full turns coutnerclockwise, then turn the bottom one (near the(c) 2005) back 7 full turnsclock-wise.
Reassemble. Be careful when sliding theunit back in, the mainboard sits on the third slot, the expander as well on thetop half.
You need to open the ECU and readjust the Crank and Cam VR conditioners.
First you'll need to slide the mainboard out of the case. Remove the two serial port studsfrom the USB side of the case. IIRC they are 3/16".
Remove the 4 screws on the opposite end-plate of the case and you can now slideit out from the dual db37 side.
You should be looking at a green expander board and a white daughter-boardconnected by two ribbons.
On the green expander board, lift the top ribbon to expose the two adjusting pots. They are gray cubes with little brass screws on them. Turn them both CCW 10 times. Then on the top one, R11, turn it CW 3 times.
Now remove the studs from the top db37 holding the green expander inplace; kinda of fold it up out of the way for access.
There are two more pots you can adjust here for the crank signal on the mainboard. Turn them both back 12 full turns coutnerclockwise, then turn the bottom one (near the(c) 2005) back 7 full turnsclock-wise.
Reassemble. Be careful when sliding theunit back in, the mainboard sits on the third slot, the expander as well on thetop half.
Last edited by Braineack; 05-13-2013 at 08:55 AM.
#15
Boost Czar
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either in the harness, or something something inside the MS failed. never had this happen before, try going further CW with r56 and see if you can get a signal, take some pics of the board while you are in there just in case.