HELP! LY6 standalone SO CLOSE
#1
Staging Lane
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HELP! LY6 standalone SO CLOSE
Hey guys, Ive been putting every second of free time and extra change into this motor the past year and I have it on the stand and its turning over but not firing.
I modified the harness myself and have power going to coils, injectors, cam and crank sensors.
I had the computers tuned by vengeance racing and was told VATS was deleted.
Its a 2008 LY6 VVT delete, LS3 intake, LS9 Cam, LS7 lifters, LS6 springs.. I just finished priming the bottom end and ended up pouring oil over the lifters hoping they would get plenty lubed up just for a short start up which should get the juices flowing. Ill be doing a write up on everything I've done to truly show the new guys that anybody can do this. Beforehand I had only done regular maintenance and a few decent repairs on my pickup.
Anyways Im dying to get this thing running where should I start troubleshooting?
1. I have the OBD2 ready to wire up but haven't done so yet so that might be the problem right there.
2. CRANK SENSOR: There could be a chance I have wires mixed up? I don't think that is the case.
3. My injectors may be stuck it has been sitting for a year.. Would some seafoam do the trick or what would you guys recommend to clear them out?
4. Could there be any hookups in the harness that are throwing a code of some sort to keep it from firing? Like the park neutral safety switch or something?
Sorry I know this post is all over the place I'm just hoping for some recommendations because Im stumped. I can post some videos of it turning over if that would help!
I modified the harness myself and have power going to coils, injectors, cam and crank sensors.
I had the computers tuned by vengeance racing and was told VATS was deleted.
Its a 2008 LY6 VVT delete, LS3 intake, LS9 Cam, LS7 lifters, LS6 springs.. I just finished priming the bottom end and ended up pouring oil over the lifters hoping they would get plenty lubed up just for a short start up which should get the juices flowing. Ill be doing a write up on everything I've done to truly show the new guys that anybody can do this. Beforehand I had only done regular maintenance and a few decent repairs on my pickup.
Anyways Im dying to get this thing running where should I start troubleshooting?
1. I have the OBD2 ready to wire up but haven't done so yet so that might be the problem right there.
2. CRANK SENSOR: There could be a chance I have wires mixed up? I don't think that is the case.
3. My injectors may be stuck it has been sitting for a year.. Would some seafoam do the trick or what would you guys recommend to clear them out?
4. Could there be any hookups in the harness that are throwing a code of some sort to keep it from firing? Like the park neutral safety switch or something?
Sorry I know this post is all over the place I'm just hoping for some recommendations because Im stumped. I can post some videos of it turning over if that would help!
#2
Staging Lane
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I have the starter wired up directly on its own.. I have ignition wired to a toggle which powers fuel pump coils injectors ect then the starter wired to a push button just for the time being..
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#8
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What fuel pressure? Which regulator?
Why haven't you wired up the OBD and checked for codes?
Does the harness have a neutral safety?
Is it spraying fuel? Do you have pressure at the rail?
No power to cam/crank sensors when key on is? What about when its cranking?
You need to hook up a scanner and see if its registering any RPM while cranking.
Why haven't you wired up the OBD and checked for codes?
Does the harness have a neutral safety?
Is it spraying fuel? Do you have pressure at the rail?
No power to cam/crank sensors when key on is? What about when its cranking?
You need to hook up a scanner and see if its registering any RPM while cranking.
#10
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The E38 ECU gets a park/neutral signal from Pin 1.
#12
Staging Lane
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Thanks for the info. Sorry for jumping the gun on the post I was anxious to get it to fire. Ive been reading and reading studying my electrical manual and trying to learn more about it and I have a ways to go.
GMLAN: Goes PCM-->TCM-->BCM-->OBD2... Ive deleted the BCMs so my two GMLAN wires (TN, TN/BK) are running from PCM and also from TCM then are cut (would have gone to BCM?). GMLAN is a continuous signal going both ways to allow communication between the PCM, TCM, BCM, and OBD2. Can I splice the high speed GMLAN + from the PCM and TCM then go into OBD2? And do the same for GMLAN -? I am wondering if the signal will still be passed in the correct order. My electrical manual has a position for GMLAN LOW SPEED in the OBD2 port but I cannot find that coming from my pcm. I only see this wire running between BCMs. Is this wire needed?
BRAKE SWITCH: Do I need to put a resistor on this pin to send a signal to the computer that the brake is pressed? Or could I hook it up directly to power and that will send the correct signal? I am now confused if the brake signal is ground and receives power when pressed or receives constant power and grounded when pressed to allow cranking.
FUEL: I had my fuel pump rigged up quick to try to crank the motor and wasn't thinking. I just hooked it to a key on in my fuse block and didn't even use my FP signal from PCM so Ill connect that up. Do I need to wire up the fuel level sender? Ive read that it will not prevent the motor from cranking but will definitely hinder its performance if I don't.
STARTER: I am going to try to replicate the schematic in my electrical manual instead of wiring up the starter the way I previously described. I didn't incorporate the starter relay solenoid because I used a fuse block I made for a LS1 harness in which I deleted this pin.
Tuning: I can't afford a tuner right now unfortunately. Is it possible to get it running without one if I have had a base tune done by vengeance racing? I had met the guy and traded a few things and he was a big help so the tune was relatively vague. He said I could send my PCM and TCM to him and hell get it tuned for 150 and I sent him my info on the build and I am hoping for the best because this was my only option at the time.
I am running mechanical gauges so I am not worried about all of those signals right now. I know some guys cash it in because of the hassle it is to get all the gauges and dash to communicate with whatever vehicle the swap is going in.
GMLAN: Goes PCM-->TCM-->BCM-->OBD2... Ive deleted the BCMs so my two GMLAN wires (TN, TN/BK) are running from PCM and also from TCM then are cut (would have gone to BCM?). GMLAN is a continuous signal going both ways to allow communication between the PCM, TCM, BCM, and OBD2. Can I splice the high speed GMLAN + from the PCM and TCM then go into OBD2? And do the same for GMLAN -? I am wondering if the signal will still be passed in the correct order. My electrical manual has a position for GMLAN LOW SPEED in the OBD2 port but I cannot find that coming from my pcm. I only see this wire running between BCMs. Is this wire needed?
BRAKE SWITCH: Do I need to put a resistor on this pin to send a signal to the computer that the brake is pressed? Or could I hook it up directly to power and that will send the correct signal? I am now confused if the brake signal is ground and receives power when pressed or receives constant power and grounded when pressed to allow cranking.
FUEL: I had my fuel pump rigged up quick to try to crank the motor and wasn't thinking. I just hooked it to a key on in my fuse block and didn't even use my FP signal from PCM so Ill connect that up. Do I need to wire up the fuel level sender? Ive read that it will not prevent the motor from cranking but will definitely hinder its performance if I don't.
STARTER: I am going to try to replicate the schematic in my electrical manual instead of wiring up the starter the way I previously described. I didn't incorporate the starter relay solenoid because I used a fuse block I made for a LS1 harness in which I deleted this pin.
Tuning: I can't afford a tuner right now unfortunately. Is it possible to get it running without one if I have had a base tune done by vengeance racing? I had met the guy and traded a few things and he was a big help so the tune was relatively vague. He said I could send my PCM and TCM to him and hell get it tuned for 150 and I sent him my info on the build and I am hoping for the best because this was my only option at the time.
I am running mechanical gauges so I am not worried about all of those signals right now. I know some guys cash it in because of the hassle it is to get all the gauges and dash to communicate with whatever vehicle the swap is going in.
#14
Staging Lane
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Working on it.. Im on hold I need to pick up a resistor for the gmlan and a relay to wire up the tcc brake switch. I also need to wire up the starter correctly with all the wires in the schematic.. I while back I used the pinouts from lt1swap and he removes the starter enable relay control so I did and I'm going to add that back along with some other things.. I am also wondering what wires for the fuel system are necessary to communicate with the pcm.
When I made the original comment, I had finally gotten the engine all assembled and rushed into trying to wire my harness up to get it to fire while it was on the stand. I have it all cut down and routed like I want it in the car and have the fuse block made and didn't realize how much more I had left. I may go ahead and put the engine in the car so I can wire up the pedal, brake, ignition, and fuel system.
Im not getting much feedback so I'm just going by my electrical manual and trying to figure it out along with a lot of google. I won't be back in my garage till Thursday at the earliest but Ill let you know if any miracles happen.
When I made the original comment, I had finally gotten the engine all assembled and rushed into trying to wire my harness up to get it to fire while it was on the stand. I have it all cut down and routed like I want it in the car and have the fuse block made and didn't realize how much more I had left. I may go ahead and put the engine in the car so I can wire up the pedal, brake, ignition, and fuel system.
Im not getting much feedback so I'm just going by my electrical manual and trying to figure it out along with a lot of google. I won't be back in my garage till Thursday at the earliest but Ill let you know if any miracles happen.
#15
Thanks for the info. Sorry for jumping the gun on the post I was anxious to get it to fire. Ive been reading and reading studying my electrical manual and trying to learn more about it and I have a ways to go.
GMLAN: Goes PCM-->TCM-->BCM-->OBD2... Ive deleted the BCMs so my two GMLAN wires (TN, TN/BK) are running from PCM and also from TCM then are cut (would have gone to BCM?). GMLAN is a continuous signal going both ways to allow communication between the PCM, TCM, BCM, and OBD2. Can I splice the high speed GMLAN + from the PCM and TCM then go into OBD2? And do the same for GMLAN -? I am wondering if the signal will still be passed in the correct order. My electrical manual has a position for GMLAN LOW SPEED in the OBD2 port but I cannot find that coming from my pcm. I only see this wire running between BCMs. Is this wire needed?
BRAKE SWITCH: Do I need to put a resistor on this pin to send a signal to the computer that the brake is pressed? Or could I hook it up directly to power and that will send the correct signal? I am now confused if the brake signal is ground and receives power when pressed or receives constant power and grounded when pressed to allow cranking.
FUEL: I had my fuel pump rigged up quick to try to crank the motor and wasn't thinking. I just hooked it to a key on in my fuse block and didn't even use my FP signal from PCM so Ill connect that up. Do I need to wire up the fuel level sender? Ive read that it will not prevent the motor from cranking but will definitely hinder its performance if I don't.
STARTER: I am going to try to replicate the schematic in my electrical manual instead of wiring up the starter the way I previously described. I didn't incorporate the starter relay solenoid because I used a fuse block I made for a LS1 harness in which I deleted this pin.
Tuning: I can't afford a tuner right now unfortunately. Is it possible to get it running without one if I have had a base tune done by vengeance racing? I had met the guy and traded a few things and he was a big help so the tune was relatively vague. He said I could send my PCM and TCM to him and hell get it tuned for 150 and I sent him my info on the build and I am hoping for the best because this was my only option at the time.
I am running mechanical gauges so I am not worried about all of those signals right now. I know some guys cash it in because of the hassle it is to get all the gauges and dash to communicate with whatever vehicle the swap is going in.
GMLAN: Goes PCM-->TCM-->BCM-->OBD2... Ive deleted the BCMs so my two GMLAN wires (TN, TN/BK) are running from PCM and also from TCM then are cut (would have gone to BCM?). GMLAN is a continuous signal going both ways to allow communication between the PCM, TCM, BCM, and OBD2. Can I splice the high speed GMLAN + from the PCM and TCM then go into OBD2? And do the same for GMLAN -? I am wondering if the signal will still be passed in the correct order. My electrical manual has a position for GMLAN LOW SPEED in the OBD2 port but I cannot find that coming from my pcm. I only see this wire running between BCMs. Is this wire needed?
BRAKE SWITCH: Do I need to put a resistor on this pin to send a signal to the computer that the brake is pressed? Or could I hook it up directly to power and that will send the correct signal? I am now confused if the brake signal is ground and receives power when pressed or receives constant power and grounded when pressed to allow cranking.
FUEL: I had my fuel pump rigged up quick to try to crank the motor and wasn't thinking. I just hooked it to a key on in my fuse block and didn't even use my FP signal from PCM so Ill connect that up. Do I need to wire up the fuel level sender? Ive read that it will not prevent the motor from cranking but will definitely hinder its performance if I don't.
STARTER: I am going to try to replicate the schematic in my electrical manual instead of wiring up the starter the way I previously described. I didn't incorporate the starter relay solenoid because I used a fuse block I made for a LS1 harness in which I deleted this pin.
Tuning: I can't afford a tuner right now unfortunately. Is it possible to get it running without one if I have had a base tune done by vengeance racing? I had met the guy and traded a few things and he was a big help so the tune was relatively vague. He said I could send my PCM and TCM to him and hell get it tuned for 150 and I sent him my info on the build and I am hoping for the best because this was my only option at the time.
I am running mechanical gauges so I am not worried about all of those signals right now. I know some guys cash it in because of the hassle it is to get all the gauges and dash to communicate with whatever vehicle the swap is going in.
#16
Staging Lane
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Hey guys sorry its been a while but Ive made some solid progress! She is up and running!
Ill try to sum up some of the issues I found and feel free to message me on here for more info.
I got to the point where I had finished modifying my harness to get the motor started up. I hadn't actually finished re-looming and cleaning up the harness but I was confident I had everything wired correctly. I was getting spark but no fuel.
1. ABSOLUTE number one rule and I know you've heard it a million times but make sure your computers (at the very least) have VATS deleted! I had my computers sent off to be tuned by vengeance racing, a very reliable and proven company, and my VATS was still active. I met a guy through this process that worked for an LS swap company that claimed he could get me a good vengeance racing tune for a good price. We had done business prior and I had no reason not to trust him. I sent my computers to him to have them tuned but I was not able to test the computers until almost a year later because I hadn't completed my engine build and harness yet. When I was at the point of trouble shooting to figure out my no fire issues, VATS was not a concern because I was confident it had been tuned out properly. I don't have HPtuners or EFIlive so I couldn't check it and can't afford to spend that kind of money on a tune right now. Well my computers got mixed up along the way and my VATS was not touched. This was frustrating in a way but somewhat of a relief because I was confident that had to be my issue at this point. I had my VATS deleted and she fired right up!
2. Make sure your injectors are working properly? This wasn't my issue but I made sure they were working properly regardless. You can do this by hooking up a small bulb to one of the pigtails on your harness. While cranking, the bulb should be flashing. If it is not, you more than likely have a VATS issue or a starter check issue. You also need to make sure they are not clogged. Injectors can clog after sitting for as little as two weeks. I tested mine by using an extra injector pigtail and hooking my injectors up to a battery with a switch. Hook a pressurized can of parts cleaner to the injector. Turn the injector on and spray cleaner into the injector and it should fire once under pressure. This will also clean the injector.
3. Make sure you have solid grounds! Also make sure you know which sensors you have and the correct pinouts for those specific sensors. Especially MAP and TPS. GMupfitter.com has been a great source for me. I have used many different pinouts from guys online for swap schematics. When it comes down to it, using the original electrical schematic from the application your setup came out of is what helps best. I even ended up helping guys that were giving me info add to there diagrams for different setups.
4. Another common question is about the GMLAN. It is not as intimidating as everyone makes it out to be. I deleted my body harness so I had the GMLAN wires cut at the BCMs. Connect the two GMLAN wires together where the BCMs used to be and run them into the DLC. It is important that the High speed (+) and (-) are the same lengths and run from ECM-TCM-DLC. A 120ohms resistor IS NOT NECESSARY at the DLC. The ECM has a resistor integrated.
5. The MAF does not need to be connected to start your motor it just won't run perfect. Also make sure all of your vacuum ports are plugged. Again, the motor will not run perfect but you should get a steady idle and be able to see if your sensors are working.
6. Electric pedal: I used a pedal/ecm/tcm from a 2008 4.8 savana van. I had a few issues with this working my LS3 throttle body. Make sure you know the schematic for your specific pedal and your specific throttle body and wire them accordingly. Once you are at KEY ON, you should hear and two step click from the blade on the TB. NOTE that this two step click can also be active when your pedal is not wired correctly and is not activating the blade. If that is the case, you more than likely need to switch the wiring on your pedal.
I used ECM/TCM/Pedal from a 2008 4.8 Van, a 2013 5.3 Van wiring harness that I modified myself, and it is running a 2008 LY6 from a Van.
LY6: VVT delete, LS9 cam, LS7 lifters, LS6 springs, LS3 intake.
Ill try to sum up some of the issues I found and feel free to message me on here for more info.
I got to the point where I had finished modifying my harness to get the motor started up. I hadn't actually finished re-looming and cleaning up the harness but I was confident I had everything wired correctly. I was getting spark but no fuel.
1. ABSOLUTE number one rule and I know you've heard it a million times but make sure your computers (at the very least) have VATS deleted! I had my computers sent off to be tuned by vengeance racing, a very reliable and proven company, and my VATS was still active. I met a guy through this process that worked for an LS swap company that claimed he could get me a good vengeance racing tune for a good price. We had done business prior and I had no reason not to trust him. I sent my computers to him to have them tuned but I was not able to test the computers until almost a year later because I hadn't completed my engine build and harness yet. When I was at the point of trouble shooting to figure out my no fire issues, VATS was not a concern because I was confident it had been tuned out properly. I don't have HPtuners or EFIlive so I couldn't check it and can't afford to spend that kind of money on a tune right now. Well my computers got mixed up along the way and my VATS was not touched. This was frustrating in a way but somewhat of a relief because I was confident that had to be my issue at this point. I had my VATS deleted and she fired right up!
2. Make sure your injectors are working properly? This wasn't my issue but I made sure they were working properly regardless. You can do this by hooking up a small bulb to one of the pigtails on your harness. While cranking, the bulb should be flashing. If it is not, you more than likely have a VATS issue or a starter check issue. You also need to make sure they are not clogged. Injectors can clog after sitting for as little as two weeks. I tested mine by using an extra injector pigtail and hooking my injectors up to a battery with a switch. Hook a pressurized can of parts cleaner to the injector. Turn the injector on and spray cleaner into the injector and it should fire once under pressure. This will also clean the injector.
3. Make sure you have solid grounds! Also make sure you know which sensors you have and the correct pinouts for those specific sensors. Especially MAP and TPS. GMupfitter.com has been a great source for me. I have used many different pinouts from guys online for swap schematics. When it comes down to it, using the original electrical schematic from the application your setup came out of is what helps best. I even ended up helping guys that were giving me info add to there diagrams for different setups.
4. Another common question is about the GMLAN. It is not as intimidating as everyone makes it out to be. I deleted my body harness so I had the GMLAN wires cut at the BCMs. Connect the two GMLAN wires together where the BCMs used to be and run them into the DLC. It is important that the High speed (+) and (-) are the same lengths and run from ECM-TCM-DLC. A 120ohms resistor IS NOT NECESSARY at the DLC. The ECM has a resistor integrated.
5. The MAF does not need to be connected to start your motor it just won't run perfect. Also make sure all of your vacuum ports are plugged. Again, the motor will not run perfect but you should get a steady idle and be able to see if your sensors are working.
6. Electric pedal: I used a pedal/ecm/tcm from a 2008 4.8 savana van. I had a few issues with this working my LS3 throttle body. Make sure you know the schematic for your specific pedal and your specific throttle body and wire them accordingly. Once you are at KEY ON, you should hear and two step click from the blade on the TB. NOTE that this two step click can also be active when your pedal is not wired correctly and is not activating the blade. If that is the case, you more than likely need to switch the wiring on your pedal.
I used ECM/TCM/Pedal from a 2008 4.8 Van, a 2013 5.3 Van wiring harness that I modified myself, and it is running a 2008 LY6 from a Van.
LY6: VVT delete, LS9 cam, LS7 lifters, LS6 springs, LS3 intake.
#19
Staging Lane
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Thanks man! Feel free to message me anytime but as of right now I just have it running on a homemade engine stand.. I should have my 2010+ Camaro water pump in couple days and can get the rest of the truck accessories up and running and maybe get a dyno run in next month so I can give you some better info on what you may want to do.. Ive been working on this harness and studying E38/gen IV for about a year now Im thinking of making some harnesses to sell that won't cost an arm and a leg..