VedemXCIX Posted January 7 Report Share Posted January 7 Hello all, thank you in advance for any and all help with this matter. I'm currently building an Chevy LV3 swapped S2000, with a T56 transmission. I have the engine in the car and mostly wired up to a G4x Monsoon. I do have a aftermarket Cam in the engine with a cam phaser limiter installed so I will not be utilizing any of the VVT system on the front of the engine. I also have the direct injection system eliminated and will be running LS1 fuel injectors from an LS1 intake. Because of this I was planning on running the engine with only the Crank angle sensor and with the ignition in a wasted spark setup. Previously I've been able to run a 5.3 on a setup very similar to this on a megasquirt. From what I've been reading it almost seems that I have to have the cam wired in order to set the timing and run the engine. Is this correct? I just wanted to double check before ordering the pigtail for the cam angle sensor. Essentially I am getting no signal from my crank sensor when attempting to turn over the engine and I believe that is my issue. I've seen on previous forum posts people talked about disabling the Cam but I can't see to find the setting to be able to do so. I have double checked my wiring for the sensor and continuity all the way from the senor to the plug in on the ECU. Secondly I wanted to double check my settings for the 60-2 crank trigger wheel that is used by the LV3. I have uploaded the tune that I currently have uploaded to the ECU for review. If anyone is willing to take a look and tell me what you think, I'd greatly appreciate it! RF1.pclx Quote Link to comment Share on other sites More sharing options...
Vaughan Posted January 7 Report Share Posted January 7 3 hours ago, VedemXCIX said: Previously I've been able to run a 5.3 on a setup very similar to this on a megasquirt. From what I've been reading it almost seems that I have to have the cam wired in order to set the timing and run the engine. Is this correct? If you are only running a crank sensor you will need to run waste spark and some form of group injection. You can still calibrate the timing and run the engine like this but you'll have two possible offsets that will both work which are 360degrees apart. 4 hours ago, VedemXCIX said: Essentially I am getting no signal from my crank sensor when attempting to turn over the engine and I believe that is my issue. I've seen on previous forum posts people talked about disabling the Cam but I can't see to find the setting to be able to do so. I have double checked my wiring for the sensor and continuity all the way from the senor to the plug in on the ECU. Trigger 2 Sync Mode should be set to None, Fuel Mode should be set to Single-Point Group or Multi-Point Group as Semi-Sequential requires a CAM sync to work properly. If you can take a trigger scope while cranking and a PCLink log of an attempted start that should show us what it is happening. Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 7 Report Share Posted January 7 You will need to turn the pull-up ON on trigger 1, and set trig 2 sync mode to none. Quote Link to comment Share on other sites More sharing options...
VedemXCIX Posted January 7 Author Report Share Posted January 7 Thank you Adam and Vaughn for the quick replies! I have made the requested changes and attempted another startup to capture the logs. It seems that trigger scope is seeing the signal from the sensor, but I'm not seeing any RPM's when cranking. Feel free to let me know if you need anything else on my end. PC Datalog - 2024-01-7 2;48;56 pm.llgx RF1.pclx Trigger Scope - 2024-01-7 2;44;34 pm.llgx Quote Link to comment Share on other sites More sharing options...
Vaughan Posted January 7 Report Share Posted January 7 Your attached trigger scope just shows electrical noise, no teeth, are you sure you pressed capture while it was cranking? If you did then the ECU isn't seeing any signal at all. Quote Link to comment Share on other sites More sharing options...
VedemXCIX Posted January 8 Author Report Share Posted January 8 15 hours ago, Vaughan said: Your attached trigger scope just shows electrical noise, no teeth, are you sure you pressed capture while it was cranking? If you did then the ECU isn't seeing any signal at all. You're absolutely correct.. I was so tired last night I didn't even notice that at first. Does it look like I might have the voltage and signal messed up? I have the crank sensor wired according to how a standard LS 58x crank sensor would be wired and I confirmed that I have the signal wire going to Trigger 1 on the ECU as seen below: Pin C is going to Trigger 1, A is +5v and B is grounded to the ECU provided Sensor Ground. Should I try flipping pins A and C and see what happens? Quote Link to comment Share on other sites More sharing options...
Vaughan Posted January 18 Report Share Posted January 18 On 1/9/2024 at 3:54 AM, VedemXCIX said: Pin C is going to Trigger 1, A is +5v and B is grounded to the ECU provided Sensor Ground. Should I try flipping pins A and C and see what happens? I don't know a whole lot about the trigger wiring on these motor but looking in the Link help manual it does look like some of the LS trigger pinouts are flipped compared to others so probably worth a shot. Quote Link to comment Share on other sites More sharing options...
VedemXCIX Posted January 27 Author Report Share Posted January 27 On 1/17/2024 at 4:27 PM, Vaughan said: I don't know a whole lot about the trigger wiring on these motor but looking in the Link help manual it does look like some of the LS trigger pinouts are flipped compared to others so probably worth a shot. I did end up trying to flip the pins and unfortunately I'm seeing the same thing on the trigger scope which is nothing.. I also put in a brand new sensor and sadly I'm not seeing a difference either. I did shine a light in the hole of the block where the sensor goes and the trigger wheel is there.. I had honestly stepped away for the past week and a half to take a breather from the project. I plan to get back in there this weekend and see if I can figure out what's going on with the sensor. Random thought. Would it be possible to run the motor from the CAS(cam angle sensor)? I know some older motors like the Nissan RB's just used their CAS for the crank sensor, would it be possible for me to try running it that way if I continue having issues with my crank sensor? Quote Link to comment Share on other sites More sharing options...
Adamw Posted January 28 Report Share Posted January 28 If you pull the sensor out of the block but leave it plugged in, then do a trigger scope with the sensor just hanging in free air (dont crank engine) you should see 3.5-5V showing on the trigger 1 trace. Then if you put something iron based in front of the sensor and do another scope capture you should then see near 0V. These tests will at least confirm the sensor is working and is wired correctly. VedemXCIX 1 Quote Link to comment Share on other sites More sharing options...
VedemXCIX Posted January 31 Author Report Share Posted January 31 On 1/28/2024 at 2:49 AM, Adamw said: If you pull the sensor out of the block but leave it plugged in, then do a trigger scope with the sensor just hanging in free air (dont crank engine) you should see 3.5-5V showing on the trigger 1 trace. Then if you put something iron based in front of the sensor and do another scope capture you should then see near 0V. These tests will at least confirm the sensor is working and is wired correctly. Adam, Thank you for this recommendation I was able to use this process to narrow down my issues. Ultimately it looks like the reason I'm having issues with the crank sensor is due to it sharing 5v's with the Throttle position sensor. I did this thinking it wouldn't be an issue(in hindsight I see how dumb this was..), however whenever moving the throttle while doing a trigger scope, I would see constant spikes on the graph for trigger 1, when I would let off, they would go away. What is the recommended way I should wire the Optical Crank sensor to the G4x? Using the picture below I currently have the sensor wired like this: C - 5v ref going pin 32 on the G4x - This is also being used as the 5v supply for the TPS. B - Sensor Ground going to pin 24 A - Signal going to pin 8 In the wiring section of PCLink there's a mention of a +8v output coming from the ECU called "CAS Voltage", however I do not see this on the Wiring information pamphlet that came with the ecu. Is there another +5v source that I can pull from or is it best to try and step down 12v to 5v externally before powering the crank sensor? Quote Link to comment Share on other sites More sharing options...
Adamw Posted February 1 Report Share Posted February 1 It is fine and normal to share the 5V output with all sensors. Moving the TPS should not affect the 5V supply, the crank sensor wont affect the 5V supply and there is no sign of a 5V issue in any of your earlier logs. So you will need to dig a bit deeper to see what the issue is with the 5V supply - perhaps the TPS is wired wrong and is shorting the 5V to gnd at one end of its travel, or perhaps there is a high resistance connection somewhere in the 5V or Gnd circuit. Only the 2 plug ECU's (Storm/Xtreme/Fury) have the 8V output pin, but this should not be needed, there are many LS* engines out there running off the shared 5V supply. They are powered by 5V in all OEM applications as far as I have seen but they do also seem to be tolerant of a 12V supply if you wanted to try. Both of those drawings you have attached are wrong for what I know as the common grey 58X sensor. Your first drawing has the keyway on the correct side but has A & C functions swapped, and the wording "ignition feed" suggests 12V instead of 5V. Your second drawing has the keyway on the wrong side, pin functions are in the correct order, but again shows 12V instead of 5V... So to clarify, I have done a quick pic below to show how the common grey Gen IV LS 58X sensor is normally wired. I have no specific information for the LV3 so Im only assuming from your comments that it is the same as a common LS* 58X sensor. Quote Link to comment Share on other sites More sharing options...
VedemXCIX Posted February 1 Author Report Share Posted February 1 Adam, Thank you for your help it really has been beneficial. I will dig into the harness today and see if I can figure out what's going on with the 5v signal. I'm thinking for now I'll start by taking the TPS out of the equation, confirming that I can get the crank sensor signal to be recognized and then add the TPS back in and troubleshoot from there. Sadly the pinouts for the LV3/Gen V SBC's crank sensors seem to be hard to find. So some of the pictures I was using were just references to what I was trying to figure out. To help clear things up here's exactly what I have: This is Chevy's Gen V cranks sensor that's being used on the newer V8's and LV3 V6's. These use the same smaller plug that the Gen V and 4 Cam angle sensor uses. This is almost half the size of the standard 58x LS connector that's been used previously. I had followed the first image below for wiring the sensor as this seemed to be the most accurate. When looking at the sensor while it is installed in the block it is installed in the same orientation as the picture above. I then used this adapter to go from that Gen V plug to 58x to help with disconnecting the sensor without having to remove the starter: https://www.ictbillet.com/gen-5-crankshaft-position-sensor-gen-4-harness-adapter.html From there I wired the 58x pigtail to the diagram posted above. Pin C lined up with the +5v pin that was coming from the bottom of the sensor when installed on the side of the block. So that is why I wired pin C to the 5v reference. With what I've provided I still believe that I have it wired in what should be the correct way, If I'm wrong please let me know. But once the TPS is out of the equation I will test and flip wires A and C if needed. Quote Link to comment Share on other sites More sharing options...
Adamw Posted February 1 Report Share Posted February 1 If either of your drawings are correct then it looks like it should be powered by 12V, not 5V. Quote Link to comment Share on other sites More sharing options...
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