$100 to anyone who can give me the right.....
12-21-2007, 05:14 PM
#62
well two things
if you have spark and fuel it should a least try to start
you should try the very primmitive way of testing spark and pull a plug and ground it to something (using isolated plies so you dont shock your self) and look for spark , and that well tell you if you have spark in the cylinders
testing the wires for spark may say you have it it but it might not be strong enough to "light up" your plugs
if you have spark and fuel it should a least try to start
you should try the very primmitive way of testing spark and pull a plug and ground it to something (using isolated plies so you dont shock your self) and look for spark , and that well tell you if you have spark in the cylinders
testing the wires for spark may say you have it it but it might not be strong enough to "light up" your plugs
Your results may vary, but that was the last one I dealt with that "made no sense" and wouldn't start.
Good luck!
12-21-2007, 06:13 PM
#63
Some of the info conflicts with another two posts you put up.
https://ls1tech.com/forums/showthrea...877&highlight=
https://ls1tech.com/forums/showthrea...003&highlight=
This one Tells a different story than what you posted in this thread.
Sounds like something happened when you loaded a tune.
https://ls1tech.com/forums/showthrea...877&highlight=
https://ls1tech.com/forums/showthrea...003&highlight=
This one
OK, I have tracked down about everything that I can thnk of, now I need some help. My car turns over but will not start. I am not getting any spark. My fuel pump primes, I have 58psi fuel pressure. I have checked all of my grounds and they are all hooked up and tight. I keep getting this u1000 and u1016 code. But after doing some research everyone says that this code is meaningless.
Also after I turn off the key the service engine soon light stays on for about 5 seconds. Kinda weird! I have tried a new PCM but it does the same thing with that pcm. I am not sure what the problem is.
It did start at one time, then I went back out loaded a tune and then it would not start. SO then I went back put the stock tune in it and it still does the same thing
Also after I turn off the key the service engine soon light stays on for about 5 seconds. Kinda weird! I have tried a new PCM but it does the same thing with that pcm. I am not sure what the problem is.
It did start at one time, then I went back out loaded a tune and then it would not start. SO then I went back put the stock tune in it and it still does the same thing
Sounds like something happened when you loaded a tune.
12-21-2007, 06:18 PM
#64
yes at first I thought that I was not getting spark, that was untill yesterday. When we checked everything. and the car has spark and fuel. The NOID light showed the injector pulsing, and the spark tool showed that I was getting spark. Everyting else is still the same.
12-21-2007, 08:51 PM
#66
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I've had PCM's fail in very strange ways. Had one that would just reboot about every 20 minutes after the car was warmed up (seemed to follow oil temp rather than ECT). Had another that would let the car start after it sat for a while, but would not hot start.
12-21-2007, 09:15 PM
#67
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I had this same prob on a 03 Tahoe. It was a rebuilder that we had no idea of the history of. I put hours and hours into it and never figured it out. It had noid pulse and spark on the spark plug tester, just like you. Tried everything you have and then some....new cam and crank sensors, PCMs, etc etc. Sent it to the stealership as a last resort and the tech said, oh yeah I have seen this before.....its the coils. He claimed all 8 coils needed to be replaced. We told him we would not pay for him to just throw parts at it but he was confident this would fix it. 8 coils and a few minutes later it was purring like a ***** cat.
12-22-2007, 02:35 PM
#68
My guess is something happened to your original puter when while uploading the new tune and OS. Causing it to lock up.
Now this is both a question and a statement. Has the 2nd puter you installed been configured for your car. If I remember right the vin in the puter has to match the vin of your car (IE the vin in your other modules) thus causing the "U" codes. I don't think you can just slap a computer in and expect it to run the car. I've never tried to just install a puter out of another vehicle with no changes but I'm pretty sure this is the case.
Here is a little info I found that may be helpful. Or maybe not either way here it is.
This information applies to all GM vehicles Using Class 2 communication.
DTC U1000 or U1255 may set current or history, with or without other DTCs.
These DTCs set when the control module does not receive a message that it was expecting from another control module, and does not know which control module did not send the message.
If the DTC U1000 or U1255 is set in history with other DTCs set current or history, diagnose the other DTCs first.
If the DTC U1000 or U1255 is set current, this usually indicates a module that is currently not communicating or a configuration issue. For example, if the control module is configured for an option (i.e., OnStar, keyless entry, memory mirrors, etc.) that the vehicle does not have, it may expect to receive a message regarding this missing feature. This would usually occur due to the control module being recently replaced and incorrectly set up.
When the DTC U1000 or U1255 is current, the module that is not communicating may not even be listed on the Tech 2 on the Diagnostic Circuit Check /Class 2 Message Monitor list.
If the DTC U1000 or U1255 has set in history without other DTCs, replacing the control module that set the DTC is most likely NOT the solution. The module that has set the code is looking for an input from another module that is not communicating. Because the module did not receive an input that it is expecting to see, it sets a U1000 or U1255 which indicates there was a loss of communications. Look at the customer's concern (i.e., intermittent, erratic tachometer operation). This will probably be a better indication of the control module that is the source of the concern.
Now this is both a question and a statement. Has the 2nd puter you installed been configured for your car. If I remember right the vin in the puter has to match the vin of your car (IE the vin in your other modules) thus causing the "U" codes. I don't think you can just slap a computer in and expect it to run the car. I've never tried to just install a puter out of another vehicle with no changes but I'm pretty sure this is the case.
Here is a little info I found that may be helpful. Or maybe not either way here it is.
This information applies to all GM vehicles Using Class 2 communication.
DTC U1000 or U1255 may set current or history, with or without other DTCs.
These DTCs set when the control module does not receive a message that it was expecting from another control module, and does not know which control module did not send the message.
If the DTC U1000 or U1255 is set in history with other DTCs set current or history, diagnose the other DTCs first.
If the DTC U1000 or U1255 is set current, this usually indicates a module that is currently not communicating or a configuration issue. For example, if the control module is configured for an option (i.e., OnStar, keyless entry, memory mirrors, etc.) that the vehicle does not have, it may expect to receive a message regarding this missing feature. This would usually occur due to the control module being recently replaced and incorrectly set up.
When the DTC U1000 or U1255 is current, the module that is not communicating may not even be listed on the Tech 2 on the Diagnostic Circuit Check /Class 2 Message Monitor list.
If the DTC U1000 or U1255 has set in history without other DTCs, replacing the control module that set the DTC is most likely NOT the solution. The module that has set the code is looking for an input from another module that is not communicating. Because the module did not receive an input that it is expecting to see, it sets a U1000 or U1255 which indicates there was a loss of communications. Look at the customer's concern (i.e., intermittent, erratic tachometer operation). This will probably be a better indication of the control module that is the source of the concern.
12-22-2007, 02:47 PM
#69
My guess is something happened to your original puter when while uploading the new tune and OS. Causing it to lock up.
Now this is both a question and a statement. Has the 2nd puter you installed been configured for your car. If I remember right the vin in the puter has to match the vin of your car (IE the vin in your other modules) thus causing the "U" codes. I don't think you can just slap a computer in and expect it to run the car. I've never tried to just install a puter out of another vehicle with no changes but I'm pretty sure this is the case.
Here is a little info I found that may be helpful. Or maybe not either way here it is.
This information applies to all GM vehicles Using Class 2 communication.
DTC U1000 or U1255 may set current or history, with or without other DTCs.
These DTCs set when the control module does not receive a message that it was expecting from another control module, and does not know which control module did not send the message.
If the DTC U1000 or U1255 is set in history with other DTCs set current or history, diagnose the other DTCs first.
If the DTC U1000 or U1255 is set current, this usually indicates a module that is currently not communicating or a configuration issue. For example, if the control module is configured for an option (i.e., OnStar, keyless entry, memory mirrors, etc.) that the vehicle does not have, it may expect to receive a message regarding this missing feature. This would usually occur due to the control module being recently replaced and incorrectly set up.
When the DTC U1000 or U1255 is current, the module that is not communicating may not even be listed on the Tech 2 on the Diagnostic Circuit Check /Class 2 Message Monitor list.
If the DTC U1000 or U1255 has set in history without other DTCs, replacing the control module that set the DTC is most likely NOT the solution. The module that has set the code is looking for an input from another module that is not communicating. Because the module did not receive an input that it is expecting to see, it sets a U1000 or U1255 which indicates there was a loss of communications. Look at the customer's concern (i.e., intermittent, erratic tachometer operation). This will probably be a better indication of the control module that is the source of the concern.
Now this is both a question and a statement. Has the 2nd puter you installed been configured for your car. If I remember right the vin in the puter has to match the vin of your car (IE the vin in your other modules) thus causing the "U" codes. I don't think you can just slap a computer in and expect it to run the car. I've never tried to just install a puter out of another vehicle with no changes but I'm pretty sure this is the case.
Here is a little info I found that may be helpful. Or maybe not either way here it is.
This information applies to all GM vehicles Using Class 2 communication.
DTC U1000 or U1255 may set current or history, with or without other DTCs.
These DTCs set when the control module does not receive a message that it was expecting from another control module, and does not know which control module did not send the message.
If the DTC U1000 or U1255 is set in history with other DTCs set current or history, diagnose the other DTCs first.
If the DTC U1000 or U1255 is set current, this usually indicates a module that is currently not communicating or a configuration issue. For example, if the control module is configured for an option (i.e., OnStar, keyless entry, memory mirrors, etc.) that the vehicle does not have, it may expect to receive a message regarding this missing feature. This would usually occur due to the control module being recently replaced and incorrectly set up.
When the DTC U1000 or U1255 is current, the module that is not communicating may not even be listed on the Tech 2 on the Diagnostic Circuit Check /Class 2 Message Monitor list.
If the DTC U1000 or U1255 has set in history without other DTCs, replacing the control module that set the DTC is most likely NOT the solution. The module that has set the code is looking for an input from another module that is not communicating. Because the module did not receive an input that it is expecting to see, it sets a U1000 or U1255 which indicates there was a loss of communications. Look at the customer's concern (i.e., intermittent, erratic tachometer operation). This will probably be a better indication of the control module that is the source of the concern.
12-22-2007, 05:38 PM
#72
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My guess is something happened to your original puter when while uploading the new tune and OS. Causing it to lock up.
Now this is both a question and a statement. Has the 2nd puter you installed been configured for your car. If I remember right the vin in the puter has to match the vin of your car (IE the vin in your other modules) thus causing the "U" codes. I don't think you can just slap a computer in and expect it to run the car. I've never tried to just install a puter out of another vehicle with no changes but I'm pretty sure this is the case.
Here is a little info I found that may be helpful. Or maybe not either way here it is.
This information applies to all GM vehicles Using Class 2 communication.
DTC U1000 or U1255 may set current or history, with or without other DTCs.
These DTCs set when the control module does not receive a message that it was expecting from another control module, and does not know which control module did not send the message.
If the DTC U1000 or U1255 is set in history with other DTCs set current or history, diagnose the other DTCs first.
If the DTC U1000 or U1255 is set current, this usually indicates a module that is currently not communicating or a configuration issue. For example, if the control module is configured for an option (i.e., OnStar, keyless entry, memory mirrors, etc.) that the vehicle does not have, it may expect to receive a message regarding this missing feature. This would usually occur due to the control module being recently replaced and incorrectly set up.
When the DTC U1000 or U1255 is current, the module that is not communicating may not even be listed on the Tech 2 on the Diagnostic Circuit Check /Class 2 Message Monitor list.
If the DTC U1000 or U1255 has set in history without other DTCs, replacing the control module that set the DTC is most likely NOT the solution. The module that has set the code is looking for an input from another module that is not communicating. Because the module did not receive an input that it is expecting to see, it sets a U1000 or U1255 which indicates there was a loss of communications. Look at the customer's concern (i.e., intermittent, erratic tachometer operation). This will probably be a better indication of the control module that is the source of the concern.
Now this is both a question and a statement. Has the 2nd puter you installed been configured for your car. If I remember right the vin in the puter has to match the vin of your car (IE the vin in your other modules) thus causing the "U" codes. I don't think you can just slap a computer in and expect it to run the car. I've never tried to just install a puter out of another vehicle with no changes but I'm pretty sure this is the case.
Here is a little info I found that may be helpful. Or maybe not either way here it is.
This information applies to all GM vehicles Using Class 2 communication.
DTC U1000 or U1255 may set current or history, with or without other DTCs.
These DTCs set when the control module does not receive a message that it was expecting from another control module, and does not know which control module did not send the message.
If the DTC U1000 or U1255 is set in history with other DTCs set current or history, diagnose the other DTCs first.
If the DTC U1000 or U1255 is set current, this usually indicates a module that is currently not communicating or a configuration issue. For example, if the control module is configured for an option (i.e., OnStar, keyless entry, memory mirrors, etc.) that the vehicle does not have, it may expect to receive a message regarding this missing feature. This would usually occur due to the control module being recently replaced and incorrectly set up.
When the DTC U1000 or U1255 is current, the module that is not communicating may not even be listed on the Tech 2 on the Diagnostic Circuit Check /Class 2 Message Monitor list.
If the DTC U1000 or U1255 has set in history without other DTCs, replacing the control module that set the DTC is most likely NOT the solution. The module that has set the code is looking for an input from another module that is not communicating. Because the module did not receive an input that it is expecting to see, it sets a U1000 or U1255 which indicates there was a loss of communications. Look at the customer's concern (i.e., intermittent, erratic tachometer operation). This will probably be a better indication of the control module that is the source of the concern.
I don't think this would cause a no start. In my LS1 third gen, I swapped all the wiring over (dash, lights, engine, everything) but the only modules I installed are the pcm and bcm. I too have the U1000 code. Plus the pcm and bcm are from different years. I havn't tried to diagnose the u code, but the car runs fine.
I vote bad pcm.
12-22-2007, 06:18 PM
#74
I think it's something to do with the VATS or the VIN code in the PCM. Also you said you have spark......but how much? You might have spark but so weak that once it's under compression it won't be strong enough. I still think it's something to do with the security or VATS? Traver
12-22-2007, 08:09 PM
#75
Here is a link to some wiring diagrams if you don't have them already. Scroll down to 2001 firebird. Should be the same as your car. According to the diagram all the vats does is enable the fuel relay and you say you have fuel. I would think that would be the main thing the vin would have to match to. As stated above you should be alright with a 99 up pcm. Assuming your confident the PCM you have is good Just in case I would still change the vin to match yours. I would go back to square 1 as much as possible. I would also try to verify ignition timing as close as you can using a timing light. I would also consider rigging up a 1 bar map sensor to a vac. source for temporary and connect it to the map sensor pig tail. Even tho your car ran before the ambient conditions may have changed enuff to affect cold starts with the 2 bar hooked up. As someone stated if you have spark, fuel, compression and halfway decent timing it should do somethin.
http://home.att.net/~subzero350/
http://home.att.net/~subzero350/
12-23-2007, 08:36 AM
#78
I have never ever seen a timing chain jump teeth other than ones that had 100,000+ miles on them. AND there is no TDC mark on an LS1 balancer.
I got a question that will be ignored.
How was vats disabled?
I got a question that will be ignored.
How was vats disabled?
12-23-2007, 09:01 AM
#79
Guys I'm telling you it's either something to do with the Vats or something with the VIN not matching with the PCM.I agree and go back to square one with your stock tune in your PCM,preferably put in by a stealership.Also if you have a PCM that's not compatable by year for your car you'll be FUBAR!
Traver
Traver 