First Start Issues..
First Start Issues.. Guys i am having some problems and i am running out of ideas.
About the car:
2003 LQ4 Stock
Ls6 Intake (With Everything)
317 heads with BTR .660 Kit
Comp Cam: 235/251 LS: 113 54-470-11 (I know this is not the ideal cam for cathedral port, but i gotta work with what i got.)
Speed Engineering Long Tubes
Tick Stage 2 T56
Whats going on:
Car will start on the tune i attached, it revs up to 4k while advancing the timing to 30+ degrees and hangs there. Then it goes wild after that. I have all the ports blocked off, so its not that. Throttle body is closed (although it doesnt react when i press the throttle). Im also having a weird issue with the ECT. It reads -37 then goe to 284, back and forth. I tried buying a new sensor, wiring it directly to the ecu nothing.
Engine block is grounded to the frame, sensors and ecu are grounded together to the frame. Block is grounded to the battery post.
Attached is the log file and tune.
Log File
Tune File
PLEASE HELP.
About the car:
2003 LQ4 Stock
Ls6 Intake (With Everything)
317 heads with BTR .660 Kit
Comp Cam: 235/251 LS: 113 54-470-11 (I know this is not the ideal cam for cathedral port, but i gotta work with what i got.)
Speed Engineering Long Tubes
Tick Stage 2 T56
Whats going on:
Car will start on the tune i attached, it revs up to 4k while advancing the timing to 30+ degrees and hangs there. Then it goes wild after that. I have all the ports blocked off, so its not that. Throttle body is closed (although it doesnt react when i press the throttle). Im also having a weird issue with the ECT. It reads -37 then goe to 284, back and forth. I tried buying a new sensor, wiring it directly to the ecu nothing.
Engine block is grounded to the frame, sensors and ecu are grounded together to the frame. Block is grounded to the battery post.
Attached is the log file and tune.
Log File
Tune File
PLEASE HELP.
Teching In
Joined: Mar 2015
Posts: 45
Likes: 0
From: Houston, Tx
Ok I have a few questions:
1- what do you mean when you say that it doesn't react when you press the throttle? Do you mean that the engine doesn't rev up or do anything?
2- I think the motor being able to idle at 4k rpm with the throttle blade closed is insane. There has to be a gigantic vacuum leak. Like, intake-isn't-even-on kind of leak. I literally cannot believe that the motor is able to "Idle" at 4k rpm with the throttle blade closed. That's bananas. The MAP isn't even struggling as though it were pulling that much airflow through the intake, meaning that that's a reading that would be totally normal for a throttle body that was halfway open at cruise or something. I see that you're logging the MAF, and it looks normal, but damn, that's insane. If, when you said earlier, you mean that the motor doesn't change rpm when you open the throttle blade, then you have a gigantic vacuum leak. If a motor doesn't change rpm when you create a giant hole in the front of it's intake, then you have a different giant hole.
3- you have a wiring issue. The ECT falling in and out like that is reeking havoc on your tune. There are TONS of modifiers based off of ECT. base running airflow, idle rpm, adaptive idle, stall saver, spark, fuel, airflow, literally all of it. ECT is a trigger in almost every single parameter the engine uses to calculate how much fuel/air/spark to give the motor. That wiring issue needs to be worked out first. It could even be a bad pin receptacle in the computer. This needs to be addressed pretty much immediately, it's a big deal.
4- do you have narrowband O2s? If so, they're not working.
5- ***I'm an idiot. I'm leaving this here to punish myself*** I think you're in and out of PE. I don't know why. the AFR commanded is swinging from the mid 8s to the mid 14s. Are you running pump gas? ***Nevermind. This is being caused by the ECT issue.***
6- next time you log, add fuel channels. Inj DC, inj pulse width, and it wouldn't hurt to go ahead and get your Wideband working through your EGR so you can see if you're running super lean.
7- set your system options correctly. You've still got them set to be a 2001 silverado. Set the system options to "1" under air pump, alt f-term and brake tqmgmt.
8- make sure your brake lights and neutral safety switch are wired correctly. I've heard of manual cars having all sorts of stupid issues because they weren't wired correctly.
9- I saw that you're pulling a cam position sensor code. Make sure that's wired correctly and if it is, then replace the sensor. That would very obviously cause hard starting issues and other weird issues. If the motor doesn't know where it's at in it's revolution then it wouldn't be able to much engine management, if any. After you get control of the engine rpms again, do a crank relearn.
I'll give this some more thought and get back to you tomorrow.
1- what do you mean when you say that it doesn't react when you press the throttle? Do you mean that the engine doesn't rev up or do anything?
2- I think the motor being able to idle at 4k rpm with the throttle blade closed is insane. There has to be a gigantic vacuum leak. Like, intake-isn't-even-on kind of leak. I literally cannot believe that the motor is able to "Idle" at 4k rpm with the throttle blade closed. That's bananas. The MAP isn't even struggling as though it were pulling that much airflow through the intake, meaning that that's a reading that would be totally normal for a throttle body that was halfway open at cruise or something. I see that you're logging the MAF, and it looks normal, but damn, that's insane. If, when you said earlier, you mean that the motor doesn't change rpm when you open the throttle blade, then you have a gigantic vacuum leak. If a motor doesn't change rpm when you create a giant hole in the front of it's intake, then you have a different giant hole.
3- you have a wiring issue. The ECT falling in and out like that is reeking havoc on your tune. There are TONS of modifiers based off of ECT. base running airflow, idle rpm, adaptive idle, stall saver, spark, fuel, airflow, literally all of it. ECT is a trigger in almost every single parameter the engine uses to calculate how much fuel/air/spark to give the motor. That wiring issue needs to be worked out first. It could even be a bad pin receptacle in the computer. This needs to be addressed pretty much immediately, it's a big deal.
4- do you have narrowband O2s? If so, they're not working.
5- ***I'm an idiot. I'm leaving this here to punish myself*** I think you're in and out of PE. I don't know why. the AFR commanded is swinging from the mid 8s to the mid 14s. Are you running pump gas? ***Nevermind. This is being caused by the ECT issue.***
6- next time you log, add fuel channels. Inj DC, inj pulse width, and it wouldn't hurt to go ahead and get your Wideband working through your EGR so you can see if you're running super lean.
7- set your system options correctly. You've still got them set to be a 2001 silverado. Set the system options to "1" under air pump, alt f-term and brake tqmgmt.
8- make sure your brake lights and neutral safety switch are wired correctly. I've heard of manual cars having all sorts of stupid issues because they weren't wired correctly.
9- I saw that you're pulling a cam position sensor code. Make sure that's wired correctly and if it is, then replace the sensor. That would very obviously cause hard starting issues and other weird issues. If the motor doesn't know where it's at in it's revolution then it wouldn't be able to much engine management, if any. After you get control of the engine rpms again, do a crank relearn.
I'll give this some more thought and get back to you tomorrow.
Last edited by 07V; Mar 19, 2018 at 12:54 AM.
Ok I have a few questions:
1- what do you mean when you say that it doesn't react when you press the throttle? Do you mean that the engine doesn't rev up or do anything?
The car does nothing when you push on the gas, it does not rev or anything.
2- I think the motor being able to idle at 4k rpm with the throttle blade closed is insane. There has to be a gigantic vacuum leak. Like, intake-isn't-even-on kind of leak. I literally cannot believe that the motor is able to "Idle" at 4k rpm with the throttle blade closed. That's bananas. The MAP isn't even struggling as though it were pulling that much airflow through the intake, meaning that that's a reading that would be totally normal for a throttle body that was halfway open at cruise or something. I see that you're logging the MAF, and it looks normal, but damn, that's insane. If, when you said earlier, you mean that the motor doesn't change rpm when you open the throttle blade, then you have a gigantic vacuum leak. If a motor doesn't change rpm when you create a giant hole in the front of it's intake, then you have a different giant hole.
I took the intake off the car last night, there is definitely a leak in 3 runners. I am picking up new gaskets from the GM dealer tonight. Will try logging with it back on with new gaskets.
3- you have a wiring issue. The ECT falling in and out like that is reeking havoc on your tune. There are TONS of modifiers based off of ECT. base running airflow, idle rpm, adaptive idle, stall saver, spark, fuel, airflow, literally all of it. ECT is a trigger in almost every single parameter the engine uses to calculate how much fuel/air/spark to give the motor. That wiring issue needs to be worked out first. It could even be a bad pin receptacle in the computer. This needs to be addressed pretty much immediately, it's a big deal.
I have tried wiring the coolant temp directly to the ecu, and nothing happens. It is however starting off at -34 now. Bad ground?
4- do you have narrowband O2s? If so, they're not working.
I do have the upper O2 sensors hooked up, they don't read anything when disconnected. Sometimes the left bank will read 240-300 while the right bank will stay around 450.
5- ***I'm an idiot. I'm leaving this here to punish myself*** I think you're in and out of PE. I don't know why. the AFR commanded is swinging from the mid 8s to the mid 14s. Are you running pump gas? ***Nevermind. This is being caused by the ECT issue.***
6- next time you log, add fuel channels. Inj DC, inj pulse width, and it wouldn't hurt to go ahead and get your Wideband working through your EGR so you can see if you're running super lean.
I am running 93 octane, residual fuel that was left from my cobra tank. I have my wide band hooked up but it will not stay on long enough to heat up the sensor and read. Ill try adding the 02 through the egr later tonight.
7- set your system options correctly. You've still got them set to be a 2001 silverado. Set the system options to "1" under air pump, alt f-term and brake tqmgmt.
Will do this tonight.
8- make sure your brake lights and neutral safety switch are wired correctly. I've heard of manual cars having all sorts of stupid issues because they weren't wired correctly.
These all work correctly. The only thing that i have tied into the swap from the mustangs harness is the starter trigger, and the ignition hot.
9- I saw that you're pulling a cam position sensor code. Make sure that's wired correctly and if it is, then replace the sensor. That would very obviously cause hard starting issues and other weird issues. If the motor doesn't know where it's at in it's revolution then it wouldn't be able to much engine management, if any. After you get control of the engine rpms again, do a crank relearn.
Do you think this could also be caused by a bad ground?
I'll give this some more thought and get back to you tomorrow.
1- what do you mean when you say that it doesn't react when you press the throttle? Do you mean that the engine doesn't rev up or do anything?
The car does nothing when you push on the gas, it does not rev or anything.
2- I think the motor being able to idle at 4k rpm with the throttle blade closed is insane. There has to be a gigantic vacuum leak. Like, intake-isn't-even-on kind of leak. I literally cannot believe that the motor is able to "Idle" at 4k rpm with the throttle blade closed. That's bananas. The MAP isn't even struggling as though it were pulling that much airflow through the intake, meaning that that's a reading that would be totally normal for a throttle body that was halfway open at cruise or something. I see that you're logging the MAF, and it looks normal, but damn, that's insane. If, when you said earlier, you mean that the motor doesn't change rpm when you open the throttle blade, then you have a gigantic vacuum leak. If a motor doesn't change rpm when you create a giant hole in the front of it's intake, then you have a different giant hole.
I took the intake off the car last night, there is definitely a leak in 3 runners. I am picking up new gaskets from the GM dealer tonight. Will try logging with it back on with new gaskets.
3- you have a wiring issue. The ECT falling in and out like that is reeking havoc on your tune. There are TONS of modifiers based off of ECT. base running airflow, idle rpm, adaptive idle, stall saver, spark, fuel, airflow, literally all of it. ECT is a trigger in almost every single parameter the engine uses to calculate how much fuel/air/spark to give the motor. That wiring issue needs to be worked out first. It could even be a bad pin receptacle in the computer. This needs to be addressed pretty much immediately, it's a big deal.
I have tried wiring the coolant temp directly to the ecu, and nothing happens. It is however starting off at -34 now. Bad ground?
4- do you have narrowband O2s? If so, they're not working.
I do have the upper O2 sensors hooked up, they don't read anything when disconnected. Sometimes the left bank will read 240-300 while the right bank will stay around 450.
5- ***I'm an idiot. I'm leaving this here to punish myself*** I think you're in and out of PE. I don't know why. the AFR commanded is swinging from the mid 8s to the mid 14s. Are you running pump gas? ***Nevermind. This is being caused by the ECT issue.***
6- next time you log, add fuel channels. Inj DC, inj pulse width, and it wouldn't hurt to go ahead and get your Wideband working through your EGR so you can see if you're running super lean.
I am running 93 octane, residual fuel that was left from my cobra tank. I have my wide band hooked up but it will not stay on long enough to heat up the sensor and read. Ill try adding the 02 through the egr later tonight.
7- set your system options correctly. You've still got them set to be a 2001 silverado. Set the system options to "1" under air pump, alt f-term and brake tqmgmt.
Will do this tonight.
8- make sure your brake lights and neutral safety switch are wired correctly. I've heard of manual cars having all sorts of stupid issues because they weren't wired correctly.
These all work correctly. The only thing that i have tied into the swap from the mustangs harness is the starter trigger, and the ignition hot.
9- I saw that you're pulling a cam position sensor code. Make sure that's wired correctly and if it is, then replace the sensor. That would very obviously cause hard starting issues and other weird issues. If the motor doesn't know where it's at in it's revolution then it wouldn't be able to much engine management, if any. After you get control of the engine rpms again, do a crank relearn.
Do you think this could also be caused by a bad ground?
I'll give this some more thought and get back to you tomorrow.
Thank you for the help! I mad some comments above, i will do those things and then report back when i have a new log.
One comment -- the commanded AFR changes based on engine temp due to open loop EQ adder table. Bouncing from 14 to 8 AFR could very well just be a symptom of the ECT going from really high to really low. Imo that is the next thing to fix after the vacuum leaks.
Edit - meant to ask, is this drive by wire or cable? If drive by wire, double check pedal connection in addition to any throttle connections.
Edit - meant to ask, is this drive by wire or cable? If drive by wire, double check pedal connection in addition to any throttle connections.
One comment -- the commanded AFR changes based on engine temp due to open loop EQ adder table. Bouncing from 14 to 8 AFR could very well just be a symptom of the ECT going from really high to really low. Imo that is the next thing to fix after the vacuum leaks.
Edit - meant to ask, is this drive by wire or cable? If drive by wire, double check pedal connection in addition to any throttle connections.
Edit - meant to ask, is this drive by wire or cable? If drive by wire, double check pedal connection in addition to any throttle connections.
Alright, i have gotten the intake manifold gaskets changed. No more reving up to 4k. It will actually attempt to idle now.
I still cant figure out this damn ECT. I have re-grounded the ecu and the sensors independently. Only showing .4 ohms when checking with a DVMM from sensor ground to battery ground.
Also it ran just enough for the wide-band to read, its at 23 lol. I noticed my injectors are for 36 lbers it looks like. So i switched that data out with the ls6 injectors. I will upload the tune tonight and log again. Thanks for everyone's help, any suggestions for the ECT? I ran a new wire directly to the ecu outside of the car and it still does the same.
I still cant figure out this damn ECT. I have re-grounded the ecu and the sensors independently. Only showing .4 ohms when checking with a DVMM from sensor ground to battery ground.
Also it ran just enough for the wide-band to read, its at 23 lol. I noticed my injectors are for 36 lbers it looks like. So i switched that data out with the ls6 injectors. I will upload the tune tonight and log again. Thanks for everyone's help, any suggestions for the ECT? I ran a new wire directly to the ecu outside of the car and it still does the same.
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Teching In
Joined: Mar 2015
Posts: 45
Likes: 0
From: Houston, Tx
the easiest course right now would be to buy a new, acdelco sensor, and run it on its own harness to the computer (pins 74&1?) and if a new sensor doesn’t read correctly with its own harness then you have a bad computer. ****, maybe the pin in the computer is just corroded. If it’s still bad then go return your sensor and get your $9 back and spend it on a new computer. If I remember right you had a p01 controller, which is like $40 on eBay.
also, if you’re still running super lean with the correct injector data then you might still have a vacuum leak. If you can get it to idle on its own go around with a can of starting fluid and try to find it.
also, if you’re still running super lean with the correct injector data then you might still have a vacuum leak. If you can get it to idle on its own go around with a can of starting fluid and try to find it.
Last edited by 07V; Mar 27, 2018 at 08:40 AM.
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Verdad Gallardo the easiest course right now would be to buy a new, acdelco sensor, and run it on its own harness to the computer (pins 74&1?) and if a new sensor doesn’t read correctly with its own harness then you have a bad computer. ****, maybe the pin in the computer is just corroded. If it’s still bad then go return your sensor and get your $9 back and spend it on a new computer. If I remember right you had a p01 controller, which is like $40 on eBay.
also, if you’re still running super lean with the correct injector data then you might still have a vacuum leak. If you can get it to idle on its own go around with a can of starting fluid and try to find it.
also, if you’re still running super lean with the correct injector data then you might still have a vacuum leak. If you can get it to idle on its own go around with a can of starting fluid and try to find it.
Alrighty, got the new wire pig tail and ran new wires to the pins above. 74 and 63 and nothing happens. Same thing.
Here is the log file though, my wide band is jumping all over the place 15-27 afr.
Also is the revised tune. Car will idle more now though!
LS6 INJETOR FILE LOG.hpl
Mustang 6.0 LS6 Injectors T56.hpt
Here is the log file though, my wide band is jumping all over the place 15-27 afr.
Also is the revised tune. Car will idle more now though!
LS6 INJETOR FILE LOG.hpl
Mustang 6.0 LS6 Injectors T56.hpt
I can't download the new log. Only the old log. But you can clearly see the ECT jumps from 28 to -39 to 82 to -39 to 68 to 133. I'm in centigrade, not farenheit. it is all over the place. The commanded AFR does seem to follow the coolant sensor. near the end of the first log, it lost the maf input, went to zero hz, showed 4.4 g/sec and then dies.
I don't like to jump to conclusions, but I'm wondering if you have a bad ECU. Your O2 mV are reading steady 450 mV, which is highly unusual for a cold start.
Diagnostic suggestion -- fail the maf at zero hz. Set the lowest cell in the maf curve to 16 g/s. See if it'll idle and hold stoic.
I don't like to jump to conclusions, but I'm wondering if you have a bad ECU. Your O2 mV are reading steady 450 mV, which is highly unusual for a cold start.
Diagnostic suggestion -- fail the maf at zero hz. Set the lowest cell in the maf curve to 16 g/s. See if it'll idle and hold stoic.
Last edited by Darth_V8r; Mar 28, 2018 at 06:58 PM.
Not quite sure how you're doing the uploads, but I can't open them. It might be on my end, but I get the error message in the browser that says the link is bad.
Testing -- when I upload one, here is how it looks. Edit -- And when I try to open it I get the same error message.
Edit again -- checked in a different thread with an attachment and the same thing, along with a comment "the attachment feature on this site has been broken for a month."
Testing -- when I upload one, here is how it looks. Edit -- And when I try to open it I get the same error message.
Edit again -- checked in a different thread with an attachment and the same thing, along with a comment "the attachment feature on this site has been broken for a month."
Last edited by Darth_V8r; Mar 29, 2018 at 07:16 AM. Reason: File does not open
WORLDS BIGGEST IDIOT AWARD GOES TOOOO! Me.
Had the pins 74 and 73 backwards.. Explained my hard starts and cam sensor error.. Car idle like a champ. Still don't think my o2s are reading correctly. And my wideband is jumping all over the place from 14-25 i think it may be because of open headers though.
Log file for working motor lol..
Idle Log
Had the pins 74 and 73 backwards.. Explained my hard starts and cam sensor error.. Car idle like a champ. Still don't think my o2s are reading correctly. And my wideband is jumping all over the place from 14-25 i think it may be because of open headers though.
Log file for working motor lol..
Idle Log
Originally Posted by Burning
WORLDS BIGGEST IDIOT AWARD GOES TOOOO! Me.
Had the pins 74 and 73 backwards.. Explained my hard starts and cam sensor error.. Car idle like a champ. Still don't think my o2s are reading correctly. And my wideband is jumping all over the place from 14-25 i think it may be because of open headers though.
Log file for working motor lol..
Idle Log
Had the pins 74 and 73 backwards.. Explained my hard starts and cam sensor error.. Car idle like a champ. Still don't think my o2s are reading correctly. And my wideband is jumping all over the place from 14-25 i think it may be because of open headers though.
Log file for working motor lol..
Idle Log
Originally Posted by G Atsma
Open headers will do that because of fresh air "back drafting" into the collector between pulses. Throws O2 sensors senseless! lol
Thats what i figured. I guess ill have to weld some pipes onto the headers and run them temporarily till i can get to the muffler shop to get the rest of the stainless exhaust fitted.
Now i have to finish wiring the fans in, and then some little things.