need help diagnose MS install problem
#1
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Car is a 94 with stock motor.
Car ran fine prior to MS install.
I removed MAF and wired IAT into the MAF harness (red and black wires).
I grounded the AEM wb to stock groud point where block is grounded under heater hoses, made sure i got a good connection.
The MS is not getting a signal nor is it communicating with laptop via serial to USB cable (i did have to install the proper software on the computer).
Car does start but runs like it does without MAF and CEL is on, runs rich on idle and lean in higher rpm, wb is very responsive to any changes in RPM.
If i disconnect MS from harness while car is running the car dies, and will not restart unless i plug MS back in or just plug factory ecu in factory harness.
Also, when harness and MS are plugged in and i turn key to ACC (still no signal to/from MS) if i wiggle the MS harness i can hear clicking sounds which sound like they are coming from the relay area...
Could it be that the harness is bad or what could i have omitted/forgotten?
On the harness some of the wires are exposed very little, not from damage, they just don't seem to have been completely taped up close to the ends, could this be the problem?
Any and all help/input is appreciated...I need it!!!
Thanks,
Dan
Car ran fine prior to MS install.
I removed MAF and wired IAT into the MAF harness (red and black wires).
I grounded the AEM wb to stock groud point where block is grounded under heater hoses, made sure i got a good connection.
The MS is not getting a signal nor is it communicating with laptop via serial to USB cable (i did have to install the proper software on the computer).
Car does start but runs like it does without MAF and CEL is on, runs rich on idle and lean in higher rpm, wb is very responsive to any changes in RPM.
If i disconnect MS from harness while car is running the car dies, and will not restart unless i plug MS back in or just plug factory ecu in factory harness.
Also, when harness and MS are plugged in and i turn key to ACC (still no signal to/from MS) if i wiggle the MS harness i can hear clicking sounds which sound like they are coming from the relay area...
Could it be that the harness is bad or what could i have omitted/forgotten?
On the harness some of the wires are exposed very little, not from damage, they just don't seem to have been completely taped up close to the ends, could this be the problem?
Any and all help/input is appreciated...I need it!!!
Thanks,
Dan
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the clicking is most likely the fuel pump turning on.
you really need to get the laptop communicating with the megatune to see what's going on.
right click on my computer > properties > hardware > device manager
when the serial cable is connected, you should see ports and see your serial cable with a COM port.
you have to make sure it's 1 2 3 or 4.
if not, go into the properties of it and change it, it's an option in there somewhere.
open Megatune and go to communications > settings. make sure the com port matches. then hit test.
most likely the fuel map needs to be tuned a bit to get the idle steady.
the leads on the harness should be fine, it's because sometimes I cut my heatshrink a little too sort, but if it was anything less than 1mm exposed I didn't worry about it.
you really need to get the laptop communicating with the megatune to see what's going on.
right click on my computer > properties > hardware > device manager
when the serial cable is connected, you should see ports and see your serial cable with a COM port.
you have to make sure it's 1 2 3 or 4.
if not, go into the properties of it and change it, it's an option in there somewhere.
open Megatune and go to communications > settings. make sure the com port matches. then hit test.
most likely the fuel map needs to be tuned a bit to get the idle steady.
the leads on the harness should be fine, it's because sometimes I cut my heatshrink a little too sort, but if it was anything less than 1mm exposed I didn't worry about it.
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sounds good...
i just don't get why the clicking sound would come from the front of the car and only while im wiggling the wires on the harness...to better explain, the clicking is in sync with how i moved the harness, and went off only if i moved the wires...
Also, the three lights on the MS, neither one lit up, ever...is that OK?
I would just hate to drive to Atl and find out that i can't get it all done because something is faulty, thats why i tried to install everything to see if it was all good...the install took really no time at all, and i dont think i omitted anything.
On the computer, when i ran the software it automatically read com2...so i didnt mess with it...the USB was lugged into the second of the two usb ports
Not sure if that could be what i was doing wrong, but would the lights on the MS not light up anyways? sorry if these are super newb questions...i am a supernewb, you know that, lol
i just don't get why the clicking sound would come from the front of the car and only while im wiggling the wires on the harness...to better explain, the clicking is in sync with how i moved the harness, and went off only if i moved the wires...
Also, the three lights on the MS, neither one lit up, ever...is that OK?
I would just hate to drive to Atl and find out that i can't get it all done because something is faulty, thats why i tried to install everything to see if it was all good...the install took really no time at all, and i dont think i omitted anything.
On the computer, when i ran the software it automatically read com2...so i didnt mess with it...the USB was lugged into the second of the two usb ports
Not sure if that could be what i was doing wrong, but would the lights on the MS not light up anyways? sorry if these are super newb questions...i am a supernewb, you know that, lol
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the spark mod literally makes them work. if you're sparking they should light. the only thing I can think of is that I installed them polar opposites (swapped the + & -). but I'm confident i didn't.
you don't get anything at all on key on, without starting it up?
you don't get anything at all on key on, without starting it up?
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The lights never come on, ever...key on or car running, not even when i move the wires on the harness...not at all
Do you think isolationg the wires where they are exosed could make a difference? I dont see it making a difference...but i dont see any other possibilities...
Do you think isolationg the wires where they are exosed could make a difference? I dont see it making a difference...but i dont see any other possibilities...
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if they are exposed and relatively close, would this affect anything, i know sparks can jump from wire to wire if they are very close but im no expert and dont know if even possible in this particular case, you know...
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go back and double check make sure MT is looking for com2 and your cable really is on com2. i wouldn't have been able to load the firmware and your map if it cannot communicate.
turn the key to ON when testing.
dont worry about the LEDs for now.
turn the key to ON when testing.
dont worry about the LEDs for now.
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i wouldn't drive it until you at least get the laptop communicating with it and get yourself a better base tune for your car.
I'm now pretty sure i simply put your LEDs in flipped, it doesn't effect anything expect not lighting up.
I'm now pretty sure i simply put your LEDs in flipped, it doesn't effect anything expect not lighting up.
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ok thats good to hear about the LEDs, have not looked inside MS, could i flip them myself or should i not bother?
i was not gonna drive the car with MS, i was gonna put it back to stock before heading that way, i wanted to make sure everything worked before i went there to find out once i get there that something is missing/not working
i will try again and report back what happens
so, the reason the car ran bad and CEL was on is because i could not tell (via MT) the MS that it should be running withoutMAF so it didnt recognize the IAT, right...thats why it didnt run good right? it makes sense to me
i was not gonna drive the car with MS, i was gonna put it back to stock before heading that way, i wanted to make sure everything worked before i went there to find out once i get there that something is missing/not working
i will try again and report back what happens
so, the reason the car ran bad and CEL was on is because i could not tell (via MT) the MS that it should be running withoutMAF so it didnt recognize the IAT, right...thats why it didnt run good right? it makes sense to me
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i wired it to the MAF Harness directly...i exposed the wires behind the MAF plug and cut the black and red (#3&4) wires and used butt connectors, made sure there was a good connection, used some force and could not pull apart
since they are not polar, it doesnt matter which one goes where, right?
since they are not polar, it doesnt matter which one goes where, right?