Need Help Plz, LS2 LS1 TB Harness, REP P1516
10-03-2010, 06:00 PM
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Need Help Plz, LS2 LS1 TB Harness, REP P1516
About a month ago I replaced LS6 TB and intake with a ported FAST and ported LS2 TB on a 98 vert. Used a caspers TB adapter that was bought back in late '07. Car was running perfect prior to install. No codes related to TPS.
After install I keep getting P1515, P1516 at WOT thus resulting in Reduced engine power.
Checked wiring on caspers' adapter, from what I can see it appears the 5 volt ref. and the low ref signal wires are backwards? Caspers wants to send the 5 volt reference to pin C and the low reference wire to pin E on the LS2 TB. But according to my schematics, that is not correct. The low reference should be at pin C and the 5 volt ref should be at pin E?
Am I correct that caspers' pins C and E are wired backwards?
To put it another way, caspers is sending my green wire from my LS1 which is the 5 volt ref wire to the C pin which is the low ref signal on the LS2 TB.
OK so I try a little experiment, I cut the purple and green wires and splice them to each other so that they are now going to the correct pins according to the schematics I have, but as soon as I turn the key it goes straight to reduced engine power. I have unhooked the battery and cleared codes each and every time. I also thought well I was just temp. using wire nuts on the splice but using the same connection type on the original way the wires came car is not in REP at start up.
I also confirmed that all the pins are tight and all connections are secure. No bent pins or anything. So if I spliced the wires to send them to their correct pins, why is it going to REP even before start up?
I am confused, angry, tired you name it. This has been an ongoing problem now for over a month. If I put the wires back to how they were originally, car will run fine normally, but as soon as I get on it, it goes REP immediately with P1516.
I originally started out 6 weeks ago using a Comtech TB, which used the LS6 mechanicals, but it went straight to REP as soon as the key went to on. Sent it back under warranty, found to be defective. Got it back week later, reinstalled it, same thing, REP immediately.
Exchanged for LS3 TB. Car ran fine normally, go WOT get REP with P1515, P1516. Spent three hours with a tuner. Nothing, still same problem. Was told by the tuner the LS3 TB would not work on the LS1 computer.
Exchange LS3 for LS2 tb. Same thing, code 1516 and REP but it did happen a little higher up in the RPM range, about 6K as opposed to 4500 before but still REP.
Additionally, I used the MAP relcator kit on the FAST, extended the vacuum hose that goes to the back of the intake, added a Z06 MAF and relocated it to the front of the TB with the required adapter harness and added a Vararam Power duct to the already present Vararam cold air intake system.
I am ready to sell this stuff and go back to LS6 TB and intake and go FI. Absolutely crazy. I am out of ideas and at this point options for keeping the FAST. Very dissapointing as prior to the car going REP this mod has really added some HP/TQ. But I cant use it.
What am I missing? I have searched on here for at lease three days prior to posting.
Any help would be appreciated.
Thanks
After install I keep getting P1515, P1516 at WOT thus resulting in Reduced engine power.
Checked wiring on caspers' adapter, from what I can see it appears the 5 volt ref. and the low ref signal wires are backwards? Caspers wants to send the 5 volt reference to pin C and the low reference wire to pin E on the LS2 TB. But according to my schematics, that is not correct. The low reference should be at pin C and the 5 volt ref should be at pin E?
Am I correct that caspers' pins C and E are wired backwards?
To put it another way, caspers is sending my green wire from my LS1 which is the 5 volt ref wire to the C pin which is the low ref signal on the LS2 TB.
OK so I try a little experiment, I cut the purple and green wires and splice them to each other so that they are now going to the correct pins according to the schematics I have, but as soon as I turn the key it goes straight to reduced engine power. I have unhooked the battery and cleared codes each and every time. I also thought well I was just temp. using wire nuts on the splice but using the same connection type on the original way the wires came car is not in REP at start up.
I also confirmed that all the pins are tight and all connections are secure. No bent pins or anything. So if I spliced the wires to send them to their correct pins, why is it going to REP even before start up?
I am confused, angry, tired you name it. This has been an ongoing problem now for over a month. If I put the wires back to how they were originally, car will run fine normally, but as soon as I get on it, it goes REP immediately with P1516.
I originally started out 6 weeks ago using a Comtech TB, which used the LS6 mechanicals, but it went straight to REP as soon as the key went to on. Sent it back under warranty, found to be defective. Got it back week later, reinstalled it, same thing, REP immediately.
Exchanged for LS3 TB. Car ran fine normally, go WOT get REP with P1515, P1516. Spent three hours with a tuner. Nothing, still same problem. Was told by the tuner the LS3 TB would not work on the LS1 computer.
Exchange LS3 for LS2 tb. Same thing, code 1516 and REP but it did happen a little higher up in the RPM range, about 6K as opposed to 4500 before but still REP.
Additionally, I used the MAP relcator kit on the FAST, extended the vacuum hose that goes to the back of the intake, added a Z06 MAF and relocated it to the front of the TB with the required adapter harness and added a Vararam Power duct to the already present Vararam cold air intake system.
I am ready to sell this stuff and go back to LS6 TB and intake and go FI. Absolutely crazy. I am out of ideas and at this point options for keeping the FAST. Very dissapointing as prior to the car going REP this mod has really added some HP/TQ. But I cant use it.
What am I missing? I have searched on here for at lease three days prior to posting.
Any help would be appreciated.
Thanks
Last edited by Ashur; 10-03-2010 at 06:03 PM.
10-03-2010, 07:28 PM
#2
Tech Contributor
About a month ago I replaced LS6 TB and intake with a ported FAST and ported LS2 TB on a 98 vert. Used a caspers TB adapter that was bought back in late '07. Car was running perfect prior to install. No codes related to TPS.
After install I keep getting P1515, P1516 at WOT thus resulting in Reduced engine power.
Checked wiring on caspers' adapter, from what I can see it appears the 5 volt ref. and the low ref signal wires are backwards? Caspers wants to send the 5 volt reference to pin C and the low reference wire to pin E on the LS2 TB. But according to my schematics, that is not correct. The low reference should be at pin C and the 5 volt ref should be at pin E?
Am I correct that caspers' pins C and E are wired backwards?
To put it another way, caspers is sending my green wire from my LS1 which is the 5 volt ref wire to the C pin which is the low ref signal on the LS2 TB.
OK so I try a little experiment, I cut the purple and green wires and splice them to each other so that they are now going to the correct pins according to the schematics I have, but as soon as I turn the key it goes straight to reduced engine power. I have unhooked the battery and cleared codes each and every time. I also thought well I was just temp. using wire nuts on the splice but using the same connection type on the original way the wires came car is not in REP at start up.
I also confirmed that all the pins are tight and all connections are secure. No bent pins or anything. So if I spliced the wires to send them to their correct pins, why is it going to REP even before start up?
I am confused, angry, tired you name it. This has been an ongoing problem now for over a month. If I put the wires back to how they were originally, car will run fine normally, but as soon as I get on it, it goes REP immediately with P1516.
I originally started out 6 weeks ago using a Comtech TB, which used the LS6 mechanicals, but it went straight to REP as soon as the key went to on. Sent it back under warranty, found to be defective. Got it back week later, reinstalled it, same thing, REP immediately.
Exchanged for LS3 TB. Car ran fine normally, go WOT get REP with P1515, P1516. Spent three hours with a tuner. Nothing, still same problem. Was told by the tuner the LS3 TB would not work on the LS1 computer.
Exchange LS3 for LS2 tb. Same thing, code 1516 and REP but it did happen a little higher up in the RPM range, about 6K as opposed to 4500 before but still REP.
Additionally, I used the MAP relcator kit on the FAST, extended the vacuum hose that goes to the back of the intake, added a Z06 MAF and relocated it to the front of the TB with the required adapter harness and added a Vararam Power duct to the already present Vararam cold air intake system.
I am ready to sell this stuff and go back to LS6 TB and intake and go FI. Absolutely crazy. I am out of ideas and at this point options for keeping the FAST. Very dissapointing as prior to the car going REP this mod has really added some HP/TQ. But I cant use it.
What am I missing? I have searched on here for at lease three days prior to posting.
Any help would be appreciated.
Thanks
After install I keep getting P1515, P1516 at WOT thus resulting in Reduced engine power.
Checked wiring on caspers' adapter, from what I can see it appears the 5 volt ref. and the low ref signal wires are backwards? Caspers wants to send the 5 volt reference to pin C and the low reference wire to pin E on the LS2 TB. But according to my schematics, that is not correct. The low reference should be at pin C and the 5 volt ref should be at pin E?
Am I correct that caspers' pins C and E are wired backwards?
To put it another way, caspers is sending my green wire from my LS1 which is the 5 volt ref wire to the C pin which is the low ref signal on the LS2 TB.
OK so I try a little experiment, I cut the purple and green wires and splice them to each other so that they are now going to the correct pins according to the schematics I have, but as soon as I turn the key it goes straight to reduced engine power. I have unhooked the battery and cleared codes each and every time. I also thought well I was just temp. using wire nuts on the splice but using the same connection type on the original way the wires came car is not in REP at start up.
I also confirmed that all the pins are tight and all connections are secure. No bent pins or anything. So if I spliced the wires to send them to their correct pins, why is it going to REP even before start up?
I am confused, angry, tired you name it. This has been an ongoing problem now for over a month. If I put the wires back to how they were originally, car will run fine normally, but as soon as I get on it, it goes REP immediately with P1516.
I originally started out 6 weeks ago using a Comtech TB, which used the LS6 mechanicals, but it went straight to REP as soon as the key went to on. Sent it back under warranty, found to be defective. Got it back week later, reinstalled it, same thing, REP immediately.
Exchanged for LS3 TB. Car ran fine normally, go WOT get REP with P1515, P1516. Spent three hours with a tuner. Nothing, still same problem. Was told by the tuner the LS3 TB would not work on the LS1 computer.
Exchange LS3 for LS2 tb. Same thing, code 1516 and REP but it did happen a little higher up in the RPM range, about 6K as opposed to 4500 before but still REP.
Additionally, I used the MAP relcator kit on the FAST, extended the vacuum hose that goes to the back of the intake, added a Z06 MAF and relocated it to the front of the TB with the required adapter harness and added a Vararam Power duct to the already present Vararam cold air intake system.
I am ready to sell this stuff and go back to LS6 TB and intake and go FI. Absolutely crazy. I am out of ideas and at this point options for keeping the FAST. Very dissapointing as prior to the car going REP this mod has really added some HP/TQ. But I cant use it.
What am I missing? I have searched on here for at lease three days prior to posting.
Any help would be appreciated.
Thanks
I will post the schematics for C5 and C6 TPS/TAC. The only thing I can tell you is, you need to ohm out the wires, one by one with a meter, and ensure they are pinned out correctly. Once you have everything wired correctly, then you can move on to troubleshooting component problems. Anyone reading this post, ALWAYS, ALWAYS, ALWAYS verify any adapter harness with a meter before install...NEVER assume they are pinned up correctly.
01-13-2011, 06:04 PM
#4
Tech Contributor
01-13-2011, 09:08 PM
#5
i have verified that the caspers harness is all in the correct positions and i have continuity end to end of the harness, i have backprobed the ls2 tb harness with the key on, and i have 4.33V on the pink (F) and the throttle is partly open, if i manually close the throttle it will go up to 5.33v, and then blue wire (D) has 1.2volts and it goes up to over 5 as the throttle opens, i thought those 2 pins were in the wrong positions so i swapped them and then tried to start the car and it starts for a second and then dies right away, where as with the original configuration the car will run and idle and responds to throttle commands, but has p1120, p1220 and p1516,
also with the key on, the throttle position doesn't move when the gas pedal is pressed.
i did find a thread in the searching that says that this is somewhat normal with cam/intake/tb swaps before a tune, (which is where i'm at) because the engine is getting more airflow then expected because of the bigger induction package and you need to edit the ETC scaler to 0.0192, raise the p1514 table for the larger tb and also add 25% to table 6101...???
i'm just worried it's not just a tuning problem and i'm having my car towed to dyno tuning tomorrow and i don't want to get there and then find it's not tuning it's a tb or wiring problem
also with the key on, the throttle position doesn't move when the gas pedal is pressed.
i did find a thread in the searching that says that this is somewhat normal with cam/intake/tb swaps before a tune, (which is where i'm at) because the engine is getting more airflow then expected because of the bigger induction package and you need to edit the ETC scaler to 0.0192, raise the p1514 table for the larger tb and also add 25% to table 6101...???
i'm just worried it's not just a tuning problem and i'm having my car towed to dyno tuning tomorrow and i don't want to get there and then find it's not tuning it's a tb or wiring problem
01-13-2011, 09:58 PM
#6
pretty sure i figured it out... i need a dr. X-link box, apparently 4 bolt throttle bodies (ls2-ls3-ls7, etc) aren't compatible with the TAC that comes in cars with 3 bolt intakes (ls1)
hope this saves others some time
http://www.torquerush.com/index.html
hope this saves others some time
http://www.torquerush.com/index.html
01-14-2011, 12:08 AM
#7
Melting Slicks
I believe the trailblazer TB like the later version 2 (2008+?) LS3 throttle bodies have the blade opening the opposite direction and it doesn't work properly with the LS1/LS6 ECM. Perhaps that is what the device the above post is correcting.
The OP needs to verify the source of the LS2 throttle body. Make sure it didn't come off a GM truck, should be a Corvette or perhaps a GTO throttle body.
The OP needs to verify the source of the LS2 throttle body. Make sure it didn't come off a GM truck, should be a Corvette or perhaps a GTO throttle body.
01-14-2011, 02:01 PM
#8
I believe the trailblazer TB like the later version 2 (2008+?) LS3 throttle bodies have the blade opening the opposite direction and it doesn't work properly with the LS1/LS6 ECM. Perhaps that is what the device the above post is correcting.
The OP needs to verify the source of the LS2 throttle body. Make sure it didn't come off a GM truck, should be a Corvette or perhaps a GTO throttle body.
The OP needs to verify the source of the LS2 throttle body. Make sure it didn't come off a GM truck, should be a Corvette or perhaps a GTO throttle body.
unfortunatly after talking with torque rush, that isn't the case, if you have a car that has 2 harness' for the throttle body (flat 6 pin and 2 pin) you can't use a newer style throttle that has the single 8pin harness, the electronics are different and the throttle body doesn't communicate with the pedal sensor, it's true that some of the trucks throttle blade opens the other way but that has no difference on the performance, the electronics are still the same as the car throttle bodies and they won't work with the ls1/ls6 this makes me wonder why caspers makes the harness for ls1/6 to ls2 throttle bodies, when i talked to the tech yesterday at caspers it sounded like he had a lot of calls about the same codes as i had, and he said 99% of the time people find out it's a throttle body problem, i guess he was right, they need to buy the translator from torque rush to make it work!
01-15-2011, 12:23 AM
#9
Melting Slicks
unfortunatly after talking with torque rush, that isn't the case, if you have a car that has 2 harness' for the throttle body (flat 6 pin and 2 pin) you can't use a newer style throttle that has the single 8pin harness, the electronics are different and the throttle body doesn't communicate with the pedal sensor................
I've had a ported 8 pin LS2 throttle body in my 02 Z06 for over two years and the Katech wiring harness plugs into the 8 pin throttle body and then into the flat 6 pin harness and the 2 pin harness. I have a forged 416ci LS3 that I installed in my 02 Z myself
01-15-2011, 12:45 AM
#10
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Wow, Ashur I seriously hope you get some good luck man, I have THE EXACT SAME ISSUE, at 6K REP codes 1515 and 1516 and when the car is warmed up I get code the codes even through city driving!
I was told it could be tuning issues or a bad throttle position sensor in the TB?
I was told it could be tuning issues or a bad throttle position sensor in the TB?
10-20-2015, 08:37 PM
#14
HOW did it work out
