B18C1 not reading pulse for ICM, anyone know next steps?
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B18C1 not reading pulse for ICM, anyone know next steps?
Hey All,
Relatively new to this forum, looking for advice on what to check next.
Vehicle: '01 Acura GSR with P73 ECU (JDM Type R) with OBD2-OBD1 harness adapter
Situation: running fine and then started running poorly above 2500 RPM, would sputter and not run higher in than 3000 RPM. Switched in stock ECU and the same thing. Tailpipe looks like the car is running rich, at least when it was having issues. I changed the fuel pump and fuel pressure regulator, pressure is good, now not getting spark on all four cylinders.
* Checked compression, all four even and good
* All timing marks line up at TDC (crank pulley, #1 piston, both cams, and distributor)
* Checked coil, it's good but no spark
* Checked ICM, it's good but it's not getting the pulse signal (yellow with green stripe wire leading to the distributor) When I go to position 1 or 2 (on the ignition) the LED test light turns off and of course does not pulse in start mode. This is with a piercing probe to the yellow with green stripe wire as ground and the positive-going to the battery.
* I have checked for proper resistance readings for the Crank Position Sensor and the cam position sensors within the distributor and they have the proper resistance.
I am guessing this is some sort of open issue since the LED test light goes out? I purchased the car a couple of months ago and I can see that there are several wires that have been spliced just above the ECU. I did check continuity above the splices to the end of the plug for the ECU and those checked out. Again it was running fantastic just last week. Advice on next detailed steps appreciated.
Relatively new to this forum, looking for advice on what to check next.
Vehicle: '01 Acura GSR with P73 ECU (JDM Type R) with OBD2-OBD1 harness adapter
Situation: running fine and then started running poorly above 2500 RPM, would sputter and not run higher in than 3000 RPM. Switched in stock ECU and the same thing. Tailpipe looks like the car is running rich, at least when it was having issues. I changed the fuel pump and fuel pressure regulator, pressure is good, now not getting spark on all four cylinders.
* Checked compression, all four even and good
* All timing marks line up at TDC (crank pulley, #1 piston, both cams, and distributor)
* Checked coil, it's good but no spark
* Checked ICM, it's good but it's not getting the pulse signal (yellow with green stripe wire leading to the distributor) When I go to position 1 or 2 (on the ignition) the LED test light turns off and of course does not pulse in start mode. This is with a piercing probe to the yellow with green stripe wire as ground and the positive-going to the battery.
* I have checked for proper resistance readings for the Crank Position Sensor and the cam position sensors within the distributor and they have the proper resistance.
I am guessing this is some sort of open issue since the LED test light goes out? I purchased the car a couple of months ago and I can see that there are several wires that have been spliced just above the ECU. I did check continuity above the splices to the end of the plug for the ECU and those checked out. Again it was running fantastic just last week. Advice on next detailed steps appreciated.