New Engine Blues
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Joined: Jul 2008
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From: Tomball Texas
New Engine Blues
OK guys, here we go....I've searched the forums, tried all of the common fixes, but nothing seems to work, or even change the issue.
The engine will start, but not run. It doesn't die immediately, it'll run for a few seconds then the RPM starts dropping and will die within 5 seconds. Total run time is about 8 seconds. If at any time I touch the throttle it'll die instantly just like turning the key off.
This is a complete new LS2 shortblock, L92 heads, LS3 intake/TB and custom cam. I've got the TB adapter harness and the cam position sensor extension harness, all is connected properly. This combo replaced a LS6 with a similar cam so I'm pretty sure the tune is close enough to at least allow the engine to start and run.
I'm getting the following codes:
P0102
P0343
P1514
C1233
C1278
U1000
U1096
I can clear all of these via the DIC except the U1233, but I don't see that as causing the issue. Once I clear all of the codes and try to start the car it does the exact same thing as described above. When I go back to the DIC I get the same codes listed.
Obviously I'm frustrated and just want to drive my car again.
Any input would be appreciated.
Troy
The engine will start, but not run. It doesn't die immediately, it'll run for a few seconds then the RPM starts dropping and will die within 5 seconds. Total run time is about 8 seconds. If at any time I touch the throttle it'll die instantly just like turning the key off.
This is a complete new LS2 shortblock, L92 heads, LS3 intake/TB and custom cam. I've got the TB adapter harness and the cam position sensor extension harness, all is connected properly. This combo replaced a LS6 with a similar cam so I'm pretty sure the tune is close enough to at least allow the engine to start and run.
I'm getting the following codes:
P0102
P0343
P1514
C1233
C1278
U1000
U1096
I can clear all of these via the DIC except the U1233, but I don't see that as causing the issue. Once I clear all of the codes and try to start the car it does the exact same thing as described above. When I go back to the DIC I get the same codes listed.
Obviously I'm frustrated and just want to drive my car again.
Any input would be appreciated.
Troy
Drifting
Joined: Apr 2008
Posts: 1,316
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From: St. Louis Mo
If this engine was just installed, I would recommend checking that a ground was overlooked. I know i did that once and had a similar situation. Once i hooked up the ground, it started. Just a suggestion. 
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From: Tomball Texas
That's the very first thing I looked for. Initially I had a no start issue, it would turn over all day long, but never start. Once I connected a missing ground it started, but has the problem as stated above.
Troy
Troy
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Joined: Jan 2007
Posts: 19,361
Likes: 1,128
From: Dyer, IN
OK guys, here we go....I've searched the forums, tried all of the common fixes, but nothing seems to work, or even change the issue.
The engine will start, but not run. It doesn't die immediately, it'll run for a few seconds then the RPM starts dropping and will die within 5 seconds. Total run time is about 8 seconds. If at any time I touch the throttle it'll die instantly just like turning the key off.
This is a complete new LS2 shortblock, L92 heads, LS3 intake/TB and custom cam. I've got the TB adapter harness and the cam position sensor extension harness, all is connected properly. This combo replaced a LS6 with a similar cam so I'm pretty sure the tune is close enough to at least allow the engine to start and run.
I'm getting the following codes:
P0102
P0343
P1514
C1233
C1278
U1000
U1096
I can clear all of these via the DIC except the U1233, but I don't see that as causing the issue. Once I clear all of the codes and try to start the car it does the exact same thing as described above. When I go back to the DIC I get the same codes listed.
Obviously I'm frustrated and just want to drive my car again.
Any input would be appreciated.
Troy
The engine will start, but not run. It doesn't die immediately, it'll run for a few seconds then the RPM starts dropping and will die within 5 seconds. Total run time is about 8 seconds. If at any time I touch the throttle it'll die instantly just like turning the key off.
This is a complete new LS2 shortblock, L92 heads, LS3 intake/TB and custom cam. I've got the TB adapter harness and the cam position sensor extension harness, all is connected properly. This combo replaced a LS6 with a similar cam so I'm pretty sure the tune is close enough to at least allow the engine to start and run.
I'm getting the following codes:
P0102
P0343
P1514
C1233
C1278
U1000
U1096
I can clear all of these via the DIC except the U1233, but I don't see that as causing the issue. Once I clear all of the codes and try to start the car it does the exact same thing as described above. When I go back to the DIC I get the same codes listed.
Obviously I'm frustrated and just want to drive my car again.
Any input would be appreciated.
Troy
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Joined: Jul 2008
Posts: 59
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From: Tomball Texas
I only removed the engine, nothing else.
I have not yet checked the feuel pressure. That's next on the list. It acts like the fuel pump isn't running after the engine starts. I do know that the pump is priming because I can hear it. And the fact that the engine actually starts. Not completely ruling out fuel at this point.
Troy
I have not yet checked the feuel pressure. That's next on the list. It acts like the fuel pump isn't running after the engine starts. I do know that the pump is priming because I can hear it. And the fact that the engine actually starts. Not completely ruling out fuel at this point.
Troy
Drifting
Joined: May 2005
Posts: 1,513
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From: Pl Grove Utah
#1 you used the correct 2X reluctor cam gear for the conversion ?
#2 the extension harness is wired correct for the cam sensor(some came with crossed pins)
#3 MAF wires undamaged,MAF itself intact ?
#4 Tune is off,probably way off,will it start,maybe ? You should try to get some help in getting a base tune for your current combo,esp if you changed injectors.
#5 the 1514 code,did you move the MAF up next to the TB ? I have seen this twice,and both times,when you try to give the car some throttle,the blade hits the airfoil inside the MAF,resetting the TB to idle only and immed setting the code.At this point,if the tune is off,you cannot feed it enough air to make it run.
#6 double check,ground on Dr rear cyl head,ground above starter on pass side of block,no pinched wires between block and bellhousing.
Best of luck,work through each problem logically and completely and you will have it running in no time !
#2 the extension harness is wired correct for the cam sensor(some came with crossed pins)
#3 MAF wires undamaged,MAF itself intact ?
#4 Tune is off,probably way off,will it start,maybe ? You should try to get some help in getting a base tune for your current combo,esp if you changed injectors.
#5 the 1514 code,did you move the MAF up next to the TB ? I have seen this twice,and both times,when you try to give the car some throttle,the blade hits the airfoil inside the MAF,resetting the TB to idle only and immed setting the code.At this point,if the tune is off,you cannot feed it enough air to make it run.
#6 double check,ground on Dr rear cyl head,ground above starter on pass side of block,no pinched wires between block and bellhousing.
Best of luck,work through each problem logically and completely and you will have it running in no time !
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From: Tomball Texas
#1 you used the correct 2X reluctor cam gear for the conversion ?
#2 the extension harness is wired correct for the cam sensor(some came with crossed pins)
#3 MAF wires undamaged,MAF itself intact ?
#4 Tune is off,probably way off,will it start,maybe ? You should try to get some help in getting a base tune for your current combo,esp if you changed injectors.
#5 the 1514 code,did you move the MAF up next to the TB ? I have seen this twice,and both times,when you try to give the car some throttle,the blade hits the airfoil inside the MAF,resetting the TB to idle only and immed setting the code.At this point,if the tune is off,you cannot feed it enough air to make it run.
#6 double check,ground on Dr rear cyl head,ground above starter on pass side of block,no pinched wires between block and bellhousing.
Best of luck,work through each problem logically and completely and you will have it running in no time !
#2 the extension harness is wired correct for the cam sensor(some came with crossed pins)
#3 MAF wires undamaged,MAF itself intact ?
#4 Tune is off,probably way off,will it start,maybe ? You should try to get some help in getting a base tune for your current combo,esp if you changed injectors.
#5 the 1514 code,did you move the MAF up next to the TB ? I have seen this twice,and both times,when you try to give the car some throttle,the blade hits the airfoil inside the MAF,resetting the TB to idle only and immed setting the code.At this point,if the tune is off,you cannot feed it enough air to make it run.
#6 double check,ground on Dr rear cyl head,ground above starter on pass side of block,no pinched wires between block and bellhousing.
Best of luck,work through each problem logically and completely and you will have it running in no time !
#2 I'll check this as well (I was unaware of this problem)
#3 All checks out good
#4 Previous combo was similar, but the tuner that I use is nearby. I'm planning to stop there tomorrow.
#5 I did not move the MAF. It's in the stock location. I did have to use a different tube to connect the MAF to the TB. I have confirmed early on that there are no mechanical interferences.
#6 All triple checked and confirmed good.
Thanks for the responses....any little bit helps.
Troy
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Drifting
Joined: May 2005
Posts: 1,513
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From: Pl Grove Utah
Troy,did you switch from a 78mm to a LS2 90mm TB with the corresponding extension harness ? Have seen pins pushed out of TPS sensor wire or bent pin in TPS sensor in TB as well.(sorry,I reread the initial post after I asked)
Last edited by highpockets; Jul 19, 2009 at 11:53 PM. Reason: reread post !
Tech Contributor
Joined: Jan 2007
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From: Dyer, IN
Ok, the fuel pump relay gets a ground through the splice pack(under the battery tray, which in turn is ground ..on the lower left side of the block. Do you have the ground on the block reconnected? (should also have a ground (woven stainless strap)that goes to the frame rail below the master cylinder. One way to veryify quickly is to pull the fuel pump relay, and jumper the contacts so the pump runs continuously, and try to start the car. I'll PM you my number if you need clarification.
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From: Tomball Texas
Which two pins do I need to jumper on the FP relay? I'm also assuming that this would happen in the fuse box which is located in the engine compartment?
I'll double check the pins on all of the TB connections.
I do have the LS3 injectors also. I had to get the adapters so that the LS6 harness would plug into the LS3 injectors.
Troy
I'll double check the pins on all of the TB connections.
I do have the LS3 injectors also. I had to get the adapters so that the LS6 harness would plug into the LS3 injectors.
Troy
Tech Contributor
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From: Dyer, IN
I'm working late if you need to call.
Melting Slicks
Joined: Aug 2000
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From: Overland Park KS
If you got the L76 kit then the map sensor moved from the back to the front so you would have needed a harness for the map sensor as well.
May sound odd but make sure the plug for the coil pack harness is not plugged in upside down
I wouldn't think you could get it to run for 8 seconds but perhaps only one side is plugged in upside down...
As mentioned before the plug on the cam sensor is a well known issue, just switch the wires around and try again...
May sound odd but make sure the plug for the coil pack harness is not plugged in upside down
I wouldn't think you could get it to run for 8 seconds but perhaps only one side is plugged in upside down...As mentioned before the plug on the cam sensor is a well known issue, just switch the wires around and try again...
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From: Tomball Texas
You are correct, rather than getting the extension harness I extended the wires myself, using the same wire size and with all soldered connections.
I'm sure that the coil packs are plugged in correctly. When it does start it's hittin' on all 8, no doubt about that.
The cam position sensor harness is already on my list of items to check.
Thanks,
Troy
I'm sure that the coil packs are plugged in correctly. When it does start it's hittin' on all 8, no doubt about that.
The cam position sensor harness is already on my list of items to check.
Thanks,
Troy
Drifting
Joined: Dec 1999
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From: Raleigh NC
Which two pins do I need to jumper on the FP relay? I'm also assuming that this would happen in the fuse box which is located in the engine compartment?
I'll double check the pins on all of the TB connections.
I do have the LS3 injectors also. I had to get the adapters so that the LS6 harness would plug into the LS3 injectors.
Troy
I'll double check the pins on all of the TB connections.
I do have the LS3 injectors also. I had to get the adapters so that the LS6 harness would plug into the LS3 injectors.
Troy
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OK guys, here we go....I've searched the forums, tried all of the common fixes, but nothing seems to work, or even change the issue.
The engine will start, but not run. It doesn't die immediately, it'll run for a few seconds then the RPM starts dropping and will die within 5 seconds. Total run time is about 8 seconds. If at any time I touch the throttle it'll die instantly just like turning the key off.
This is a complete new LS2 shortblock, L92 heads, LS3 intake/TB and custom cam. I've got the TB adapter harness and the cam position sensor extension harness, all is connected properly. This combo replaced a LS6 with a similar cam so I'm pretty sure the tune is close enough to at least allow the engine to start and run.
I'm getting the following codes:
P0102
P0343
P1514
C1233
C1278
U1000
U1096
I can clear all of these via the DIC except the U1233, but I don't see that as causing the issue. Once I clear all of the codes and try to start the car it does the exact same thing as described above. When I go back to the DIC I get the same codes listed.
Obviously I'm frustrated and just want to drive my car again.
Any input would be appreciated.
Troy
The engine will start, but not run. It doesn't die immediately, it'll run for a few seconds then the RPM starts dropping and will die within 5 seconds. Total run time is about 8 seconds. If at any time I touch the throttle it'll die instantly just like turning the key off.
This is a complete new LS2 shortblock, L92 heads, LS3 intake/TB and custom cam. I've got the TB adapter harness and the cam position sensor extension harness, all is connected properly. This combo replaced a LS6 with a similar cam so I'm pretty sure the tune is close enough to at least allow the engine to start and run.
I'm getting the following codes:
P0102
P0343
P1514
C1233
C1278
U1000
U1096
I can clear all of these via the DIC except the U1233, but I don't see that as causing the issue. Once I clear all of the codes and try to start the car it does the exact same thing as described above. When I go back to the DIC I get the same codes listed.
Obviously I'm frustrated and just want to drive my car again.
Any input would be appreciated.
Troy
Swap pins A and C on the camshaft position sensor harness at the end that connects to the CPS. This is a necessary thing when moving to a LS2/3 CPS on a LS1 car. We found it out the hard way when my LS3 shortblock went it, and I was throwing the exact same P-Codes as you. My car went from initially running the first time to cranking only, and as soon as those pins got swapped it fired, idled, and acted normal.