GM DIS questions
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GM DIS questions
Ok, i have a 96 cavalier with dis. the car originally had a OBDII ignition module that the megasquirt cannot control. I removed it and wired the older style into it and now i have a non-functioning tach and no idle control. the ECU is not seeing any engine rotation.
I piggy-backed the VR sensor and wired in the OBDII module into the fenderwell with no coils hooked up to it and the ref pulse low and hi not attatched as well. (the ref pulse low and hi for the older module are wired into the ECU, so it should be seeing rotation).
should i make a resistor pack to simulate coils?
should i remove the ref pulse signals from the older module and replace them with the OBDII module? will that mess up my ignition advance signal to the current module?
hopefully you gm dis people can help me out with this
wopontour, any suggestions?
Brandon
codebase and megatune version shouldnt have any effect on any of this, however i am running the latest megatune, MSII version 2.3 (i think) and the V3 board.
I piggy-backed the VR sensor and wired in the OBDII module into the fenderwell with no coils hooked up to it and the ref pulse low and hi not attatched as well. (the ref pulse low and hi for the older module are wired into the ECU, so it should be seeing rotation).
should i make a resistor pack to simulate coils?
should i remove the ref pulse signals from the older module and replace them with the OBDII module? will that mess up my ignition advance signal to the current module?
hopefully you gm dis people can help me out with this
wopontour, any suggestions?
Brandon
codebase and megatune version shouldnt have any effect on any of this, however i am running the latest megatune, MSII version 2.3 (i think) and the V3 board.
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I swapped my ICM with an OBI and it works fine. I'd make sure your VR sensor's polarity is correct to the ICM. Make sure the grounds are good. One should go directly to the ECU. Besides that I'm not sure what your trying to ask?
A.J.
A.J.
1999 Saturn SC2 1.9L DOHC 4 cyl NA
MS II Blue Processor w/ 2.686t5 Beta Code
V3 PCB
MegaTune 2.25
Innovate LC1 WB O2 Sensor
OBD I Saturn Wasted Spark DIS
w/ Cooling Fan and IAC
MS II Blue Processor w/ 2.686t5 Beta Code
V3 PCB
MegaTune 2.25
Innovate LC1 WB O2 Sensor
OBD I Saturn Wasted Spark DIS
w/ Cooling Fan and IAC
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it is. the wire colors are the same on the two years of connectors i have.bluetrepidation wrote:I'd make sure your VR sensor's polarity is correct to the ICM.
A.J.
they are.bluetrepidation wrote:. Make sure the grounds are good.
A.J.
it does. stock wiring used on the engine, just stole certain wires from the ecu.bluetrepidation wrote: One should go directly to the ECU.
A.J.
I'm trying to get the tach to work and get the ECU to control the idle speed motor. it is not seeing revolutions. do i have to have teh injector circuit hooked to something? right now i just have the injector leads cut and wired to the MS.bluetrepidation wrote: Besides that I'm not sure what your trying to ask?
A.J.
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the signal to the in dash tach is not working. this is not a standard tachometer either, its a serial bus gauge cluster. there is no "tach feed" to the dash. its all in the ECU.
yes, the rpm's work in megatune. its not a matter of the megasquirt not getting a tach signal, its a matter of telling the factory computer that the engine is rotating. when that happens the tach will work and the idle motor will work.
let me repeat: the factory ecu is NOT seeing engine rotation for some reason or another. will my previous ideas work? anyone know?
yes, the rpm's work in megatune. its not a matter of the megasquirt not getting a tach signal, its a matter of telling the factory computer that the engine is rotating. when that happens the tach will work and the idle motor will work.
let me repeat: the factory ecu is NOT seeing engine rotation for some reason or another. will my previous ideas work? anyone know?
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this is what i tried. ALTHOUGH i have not wired in the reference pulse high and low yet. currently the older MS controlled module is sending the reference pulses. i think im going to try and patch the ref pulse wires into the factory ecu and just run the MS controlled one to the ms and then to ground. that way it follows along with the schematics for the DIS/HEI setup.
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Any reason not to let Megasquirt control your idle ? And try wiring direct into the tacho ?
If those are the only two functions you need from the old ECU that is.
James
If those are the only two functions you need from the old ECU that is.
James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk
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My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
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well, i figured it out. heres what i did.
i used the factory ignition module in the wheelwell. i removed the signal for reference pulse from the mocule thats controlling the ignition to the ECU and ran it JUST to the megasquirt and grounded the low line. (just like it shows for GMDIS setup pages) i then ran all the wires from the factory mocule to the ecu and pigybacked the VR sensor wires so that it would have a sensor signal from the crank. works like a charm.
i used the factory ignition module in the wheelwell. i removed the signal for reference pulse from the mocule thats controlling the ignition to the ECU and ran it JUST to the megasquirt and grounded the low line. (just like it shows for GMDIS setup pages) i then ran all the wires from the factory mocule to the ecu and pigybacked the VR sensor wires so that it would have a sensor signal from the crank. works like a charm.