Car running like shit, replaced everything...wtf!
#1
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Ok im serious about burning this car to the ground and pissing on its ashes...
Car was running fine couple days ago, then it started to sputter and it cleared up, I thought it was bad gas but I guess it wasnt.
Quick run down of new parts
-Opti (less then 3 months old)
-Coil (less then year)
-ICM (less then 3 months old)
-MSD wires ( less then year old)
-Plugs, 02 sensors, Walbro fuel pump w/ relay harness (less then year old)
-Battery good
-Alternator good
-FPR vacuum hose has no fuel in it so thats good
Now, when I start the car up its hard to start, then it fires up. It idles at around 500-600 for a couple seconds, then the volts start to fluctuate between 11v and 15v, then the cars idle gets retarded and it jumps to around 1200-1400 and sinks back down to 500 and jumps up again to 1200-1400 and eventually it dies.
Now I checked for vacuum leaks and cant find any. It threw a 36 DTC code and im getting things from, Bad Air sensor (its SD tuned from the factory so I dont have one) to Ignition circuit bad (I checked the opti harness and thats good)
I tried to be as detailed as possible so sorry for the long read. Any ideas?
Car was running fine couple days ago, then it started to sputter and it cleared up, I thought it was bad gas but I guess it wasnt.
Quick run down of new parts
-Opti (less then 3 months old)
-Coil (less then year)
-ICM (less then 3 months old)
-MSD wires ( less then year old)
-Plugs, 02 sensors, Walbro fuel pump w/ relay harness (less then year old)
-Battery good
-Alternator good
-FPR vacuum hose has no fuel in it so thats good
Now, when I start the car up its hard to start, then it fires up. It idles at around 500-600 for a couple seconds, then the volts start to fluctuate between 11v and 15v, then the cars idle gets retarded and it jumps to around 1200-1400 and sinks back down to 500 and jumps up again to 1200-1400 and eventually it dies.
Now I checked for vacuum leaks and cant find any. It threw a 36 DTC code and im getting things from, Bad Air sensor (its SD tuned from the factory so I dont have one) to Ignition circuit bad (I checked the opti harness and thats good)
I tried to be as detailed as possible so sorry for the long read. Any ideas?
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#16
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All 4 should have continuity when the ignition is on?
EDIT: Found this on shbox
![](http://shbox.com/1/95_ign_system_schematic.jpg)
Disconnect the ICM connector. Leave coil connected.
Turn key to ON.
Check for dc voltage with a digital meter at harness terminal "A" to ground and and also "D" to ground. Note: Use a high impedance meter (at least 10 megohm) when dealing with the PCM.
Result should be 10v dc or more on both terminals. If you get no voltage, use the diagram and chase back toward the coil and the ignition fuse. Power for the ICM comes from the ignition fuse and through the coil, so any of that could be bad.
If you have good voltage, switch the meter to ac scale and connect test leads to terminal "B" and to ground. Observe meter while cranking the engine. You should see between 1 and 4 volts ac (those are the pulses that trigger the coil to fire).
If you don't see the proper ac voltage the problem could be the optispark, the harness to the optispark, the PCM or any of the wiring in between. Visually inspect all the connections you can get to for poor contact or corrosion.
#17
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UPDATE:
Did the test as per the instructions above and I think this is the correct setting for the multimeter, if not please let me know lol
![](http://i19.photobucket.com/albums/b160/2fast4urass/Photo0346.jpg)
But yeah, i tested both terminal "A" and "D" with the ICM unplugged and key on and got
A- 4.74v
D- 0.002v
So it says to check the ignition fuse and coil. Im gonna take the coil off and get the ohms. Stock coil has around 8000 ohms (says on shbox website) what should an MSD coil have?
Did the test as per the instructions above and I think this is the correct setting for the multimeter, if not please let me know lol
![](http://i19.photobucket.com/albums/b160/2fast4urass/Photo0346.jpg)
But yeah, i tested both terminal "A" and "D" with the ICM unplugged and key on and got
A- 4.74v
D- 0.002v
So it says to check the ignition fuse and coil. Im gonna take the coil off and get the ohms. Stock coil has around 8000 ohms (says on shbox website) what should an MSD coil have?
#18
TECH Senior Member
iTrader: (36)
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UPDATE:
Did the test as per the instructions above and I think this is the correct setting for the multimeter, if not please let me know lol
![](http://i19.photobucket.com/albums/b160/2fast4urass/Photo0346.jpg)
But yeah, i tested both terminal "A" and "D" with the ICM unplugged and key on and got
A- 4.74v
D- 0.002v
So it says to check the ignition fuse and coil. Im gonna take the coil off and get the ohms. Stock coil has around 8000 ohms (says on shbox website) what should an MSD coil have?
Did the test as per the instructions above and I think this is the correct setting for the multimeter, if not please let me know lol
![](http://i19.photobucket.com/albums/b160/2fast4urass/Photo0346.jpg)
But yeah, i tested both terminal "A" and "D" with the ICM unplugged and key on and got
A- 4.74v
D- 0.002v
So it says to check the ignition fuse and coil. Im gonna take the coil off and get the ohms. Stock coil has around 8000 ohms (says on shbox website) what should an MSD coil have?
If so, you have a wiring issue to your ICM somewhere.
#20
TECH Senior Member
iTrader: (36)
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You can see the three different eyelets in this picture on the right stud:
http://shbox.com/1/coil_loc.jpg
One of those grounds is a braded ground strap that bolts to the driver side of the chassis.