No throttle on LQ4 swap.
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Teching In
Joined: Apr 2016
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No throttle on LQ4 swap. Trying to trouble shoot this issue, my lq4 (donor motor is a 2005 w/ 100k mi) in my 80 series toyota landcruiser, starts just fine, I hit the gas pedal once to get it revved up and it starts to rev up but then goes into "limp mode." after that, the gas pedal does nothing.
Below are the codes I am getting, but I believe it to be the p1518 code???
0x10: P0118 - Engine Coolant Temperature Sensor 1 Circuit High (Pending, History)
0x10: P0463 - Fuel Level Sensor A Circuit High (Pending, Current)
0x10: P0522 - Engine Oil Pressure Sensor/Switch Circuit Low (Current)
0x10: P0740 - Torque Converter Clutch Solenoid Circuit / Open (Pending)
0x10: P0785 - Shift/Timing Solenoid (SES, Pending, Current)
0x10: P1518 (Pending, Current, History)
0x10: P1571 (Pending, History)
0x10: P1689 (SES, Current)
I've checked the continuity between throttle body & TAC, everything is 0.3 ohm or less. Tested between gas pedal & TAC, 6 wires are below 0.3 ohm. Ground continuity back to battery is 0.1 ohm. +12V is 11.7V. Serial to ECM are both ~4.7V.
One thought is since I am having a hard time getting out of idle, the battery isn't charging and maybe it is throwing off the TAC having to jump the car from another battery every time?
Another thought is to replace the TAC, but I hate to throw more parts at it before knowing what the real problem is. I'm open to any other thoughts or things I can check??? Thanks in advance to any help you can provide.
Below are the codes I am getting, but I believe it to be the p1518 code???
0x10: P0118 - Engine Coolant Temperature Sensor 1 Circuit High (Pending, History)
0x10: P0463 - Fuel Level Sensor A Circuit High (Pending, Current)
0x10: P0522 - Engine Oil Pressure Sensor/Switch Circuit Low (Current)
0x10: P0740 - Torque Converter Clutch Solenoid Circuit / Open (Pending)
0x10: P0785 - Shift/Timing Solenoid (SES, Pending, Current)
0x10: P1518 (Pending, Current, History)
0x10: P1571 (Pending, History)
0x10: P1689 (SES, Current)
I've checked the continuity between throttle body & TAC, everything is 0.3 ohm or less. Tested between gas pedal & TAC, 6 wires are below 0.3 ohm. Ground continuity back to battery is 0.1 ohm. +12V is 11.7V. Serial to ECM are both ~4.7V.
One thought is since I am having a hard time getting out of idle, the battery isn't charging and maybe it is throwing off the TAC having to jump the car from another battery every time?
Another thought is to replace the TAC, but I hate to throw more parts at it before knowing what the real problem is. I'm open to any other thoughts or things I can check??? Thanks in advance to any help you can provide.
Thread Starter
Teching In
Joined: Apr 2016
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Sorry, I'm new to all this "tuning" stuff. Not sure what is meant by "base tune," but I haven't done any "tuning" outside of turning off VATS, if you want to count that.
I did the harness work myself. I stripped the harness down, depinned everything at the ECM, routed the wires, check the continuity according to the wiring diagram before I plugged it back into the computer.
I'm open to suggestions on how to use hptuners more effectively to troubleshoot this problem, but I am a novice to the program....
Thanks again for any help.
I did the harness work myself. I stripped the harness down, depinned everything at the ECM, routed the wires, check the continuity according to the wiring diagram before I plugged it back into the computer.
I'm open to suggestions on how to use hptuners more effectively to troubleshoot this problem, but I am a novice to the program....
Thanks again for any help.
Trying to trouble shoot this issue, my lq4 (donor motor is a 2005 w/ 100k mi) in my 80 series toyota landcruiser, starts just fine, I hit the gas pedal once to get it revved up and it starts to rev up but then goes into "limp mode." after that, the gas pedal does nothing.
Below are the codes I am getting, but I believe it to be the p1518 code???
0x10: P0118 - Engine Coolant Temperature Sensor 1 Circuit High (Pending, History)
0x10: P0463 - Fuel Level Sensor A Circuit High (Pending, Current)
0x10: P0522 - Engine Oil Pressure Sensor/Switch Circuit Low (Current)
0x10: P0740 - Torque Converter Clutch Solenoid Circuit / Open (Pending)
0x10: P0785 - Shift/Timing Solenoid (SES, Pending, Current)
0x10: P1518 (Pending, Current, History)
0x10: P1571 (Pending, History)
0x10: P1689 (SES, Current)
I've checked the continuity between throttle body & TAC, everything is 0.3 ohm or less. Tested between gas pedal & TAC, 6 wires are below 0.3 ohm. Ground continuity back to battery is 0.1 ohm. +12V is 11.7V. Serial to ECM are both ~4.7V.
One thought is since I am having a hard time getting out of idle, the battery isn't charging and maybe it is throwing off the TAC having to jump the car from another battery every time?
Another thought is to replace the TAC, but I hate to throw more parts at it before knowing what the real problem is. I'm open to any other thoughts or things I can check??? Thanks in advance to any help you can provide.
Below are the codes I am getting, but I believe it to be the p1518 code???
0x10: P0118 - Engine Coolant Temperature Sensor 1 Circuit High (Pending, History)
0x10: P0463 - Fuel Level Sensor A Circuit High (Pending, Current)
0x10: P0522 - Engine Oil Pressure Sensor/Switch Circuit Low (Current)
0x10: P0740 - Torque Converter Clutch Solenoid Circuit / Open (Pending)
0x10: P0785 - Shift/Timing Solenoid (SES, Pending, Current)
0x10: P1518 (Pending, Current, History)
0x10: P1571 (Pending, History)
0x10: P1689 (SES, Current)
I've checked the continuity between throttle body & TAC, everything is 0.3 ohm or less. Tested between gas pedal & TAC, 6 wires are below 0.3 ohm. Ground continuity back to battery is 0.1 ohm. +12V is 11.7V. Serial to ECM are both ~4.7V.
One thought is since I am having a hard time getting out of idle, the battery isn't charging and maybe it is throwing off the TAC having to jump the car from another battery every time?
Another thought is to replace the TAC, but I hate to throw more parts at it before knowing what the real problem is. I'm open to any other thoughts or things I can check??? Thanks in advance to any help you can provide.
Thread Starter
Teching In
Joined: Apr 2016
Posts: 21
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10-4. I have dakota digital sensors for temp and oil p, I don't remember seeing if they feed the correct voltages into the GM ecm....I'll track that down and hook them up. I'm running a 4l80e and have an ecm for a 4l60e (it's an emissions thing), so I'll work on getting the correct transmission file into the ECM I need for emissions. It may be easier to just spill another $100 and change the VIN on the ECM that came with the vehicle?
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10-4. I have dakota digital sensors for temp and oil p, I don't remember seeing if they feed the correct voltages into the GM ecm....I'll track that down and hook them up. I'm running a 4l80e and have an ecm for a 4l60e (it's an emissions thing), so I'll work on getting the correct transmission file into the ECM I need for emissions. It may be easier to just spill another $100 and change the VIN on the ECM that came with the vehicle?
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Verdad Gallardo 3.0 has it I believe. You don't need to tap your thermostat. The factory temp sender is in the drivers head at the front. There is a plug in the rear passengers head that you can remove and install the sender. The DD kit comes with the correct adapter.
Thread Starter
Teching In
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Got the coolant sensors hooked up. Kind of a "duh" moment when I was removing the plug on passenger side - GM only makes one head for both sides....code eliminated.
Got the tranny segment swap done. Super easy with hptuners. got the tranny codes eliminated.
I haven't hooked up the oil pressure, any suggestions on where to get the tee for that thing? I turned that code off in hptuners for the time being.
I turned off the fuel level code.
I also turned off 1571 and 1689 as they are related to traction control.
Still left with 1518. Gas pedal works up to 2000 rpm and then it goes into limp mode. Autozone warrantied out my battery, so that is fresh....
Got the tranny segment swap done. Super easy with hptuners. got the tranny codes eliminated.
I haven't hooked up the oil pressure, any suggestions on where to get the tee for that thing? I turned that code off in hptuners for the time being.
I turned off the fuel level code.
I also turned off 1571 and 1689 as they are related to traction control.
Still left with 1518. Gas pedal works up to 2000 rpm and then it goes into limp mode. Autozone warrantied out my battery, so that is fresh....
Great, good start. Post a copy of your tune. Did the tranny codes go away or did you turn them off? Did you check the transmission plug and reseat it?
I would double check my pedal wiring and tach module wiring. Recheck all of your grounds. You could possibly have a bad tach module, but I think it's something simpler than that. Check out these threads:
http://www.corvetteforum.com/forums/...sap-p1518.html
http://www.corvetteforum.com/forums/...indicator.html
Your local hardware store should have the correct fitting for you to create a "T" for the oil pressure. The threads in the block are 1/8" pipe. There's an oil block off plate on the drivers side by the oil pan that some people drill and tap but thats a little more involved.
I would double check my pedal wiring and tach module wiring. Recheck all of your grounds. You could possibly have a bad tach module, but I think it's something simpler than that. Check out these threads:
http://www.corvetteforum.com/forums/...sap-p1518.html
http://www.corvetteforum.com/forums/...indicator.html
Your local hardware store should have the correct fitting for you to create a "T" for the oil pressure. The threads in the block are 1/8" pipe. There's an oil block off plate on the drivers side by the oil pan that some people drill and tap but thats a little more involved.
Last edited by Hart_Rod; Feb 11, 2017 at 07:32 AM.
Thread Starter
Teching In
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tranny codes went away themselves with the segment swap. Along with the coolant temp code. Everything else either is still pending or has been turned off in hptuners.
When you say to post my tune, I assume you mean the *.hpt file?
I've also written down each pin that corresponds to the TAC and tested each one. I used the wiring diagrams to ensure everything was pinned correctly (in other words, I wasn't guessing - I would say pin A @ throttle body to pin 1 @ TAC or whatever it is). All resistance pretty much checked out at 0.3 ohms or less. I haven't tested each ground, but I moved the TAC ground back to the battery itself. I know I triple checked for each ground when originally wiring. And I know my ground points are good!
I also tried going through the gear chatter trouble shooting thread for p1518, but it is for a different TAC and APP. Also, it is a bit over my head.
I'll check those other threads out. I worry it may be the TAC because before I got my hood on I had the TAC and gas pedal sitting on top of the motor. It was tarped, but sometimes it would blow off which is also when it would be raining/snowing. I'd like to be pretty darn sure it is the issue before I plop down for another one.
Thanks again.
When you say to post my tune, I assume you mean the *.hpt file?
I've also written down each pin that corresponds to the TAC and tested each one. I used the wiring diagrams to ensure everything was pinned correctly (in other words, I wasn't guessing - I would say pin A @ throttle body to pin 1 @ TAC or whatever it is). All resistance pretty much checked out at 0.3 ohms or less. I haven't tested each ground, but I moved the TAC ground back to the battery itself. I know I triple checked for each ground when originally wiring. And I know my ground points are good!
I also tried going through the gear chatter trouble shooting thread for p1518, but it is for a different TAC and APP. Also, it is a bit over my head.
I'll check those other threads out. I worry it may be the TAC because before I got my hood on I had the TAC and gas pedal sitting on top of the motor. It was tarped, but sometimes it would blow off which is also when it would be raining/snowing. I'd like to be pretty darn sure it is the issue before I plop down for another one.
Thanks again.
Thread Starter
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so, if I really punch the pedal, it causes the 1518 code to trip and it goes into limp mode. if I gradually increase the throttle, i have no issues. I messed with it for about 10 mins going up and down, all the way up to 4000 rpm. No idea what is going on???
I did notice TPS % is not showing on the scanner?
I did notice TPS % is not showing on the scanner?
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Ok, I was using a 2003 PCM for a 2005 motor (and different TAC/APP). I updated to a 2005 tune. It has eliminated the P1518 code, but now I have the same behavior with the vehicle going into limp mode and a U0107 code - communication error with TAC. I've gone over the wiring a bunch of times, I am thinking I may try to replace parts at this point....unless there are any other ideas????
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Following up, some 18 months later. I sent the truck to a guy who made a lot of promises, delivered on none except the tune (which is a hoax) and a $350 bill 7 months later. I got the truck back, same limp mode issues. I'm basically at the point where I am throwing up hail marys, so I read on here that someone used the other TAC module. My engine came with the "K" module and the plastic pedal. I ordered on ebay a metal pedal and the "E" module. After dragging my feet for a couple weeks to get my battery warrantied out the 8th time at Autozone, I finally plugged the new module in last night and IT WORKS!!! NO LIMP MODE. It makes no sense to me since I bought a complete pull out motor?? And the plastic pedal works with the "E" TAC as well. Kind of odd....
Now I need to fix the shifter linkage the tuner broke, or that I half assed, and take this bad boy for a spin.
Now I need to fix the shifter linkage the tuner broke, or that I half assed, and take this bad boy for a spin.
Staging Lane
Joined: Sep 2018
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Mind if I pick your brains? I've got an LQ9 that won't rev properly. The throttle pedal appears to react to the plate fine throughout its full range, but when I try to rev the engine to above 1250 rpm it dies back to idle. I can do this repeatedly, the throttle doesn't stop responding.
I have a 2006/2007 PCM and harness and a metal pedal and TAC module. From what I could tell, all the TAC modules were the same P/N from 2003 up until when they went to the different ecu that didn't use a separate tac module, what is the "k" and "e" you refer to? Do you still have the "k" module?
I have a 2006/2007 PCM and harness and a metal pedal and TAC module. From what I could tell, all the TAC modules were the same P/N from 2003 up until when they went to the different ecu that didn't use a separate tac module, what is the "k" and "e" you refer to? Do you still have the "k" module?