LY6 Crank No Start(yes another)
Thread Starter
Teching In
Joined: Feb 2013
Posts: 7
Likes: 0
LY6 Crank No Start(yes another) Little background:
2007, 6.0L, LY6, E38, Reworked Harness, 85 K5 Blazer
Issue:
At key on the pump comes on for 2 sec. when cranking it has power to ecm injectors and coils, but its not getting spark or noid light.
Things I have tried:
-Replaced crank sensor.
-Tested wiring to Crank and camshaft sensors for continuity and for shorts
-Made sure its getting 12v to ECM and Coils in run and start(crank)
Only thing i can think of to test/Replace is cam sensor...
Anyone have some insight or past experiences?
Thanks in advance!!
2007, 6.0L, LY6, E38, Reworked Harness, 85 K5 Blazer
Issue:
At key on the pump comes on for 2 sec. when cranking it has power to ecm injectors and coils, but its not getting spark or noid light.
Things I have tried:
-Replaced crank sensor.
-Tested wiring to Crank and camshaft sensors for continuity and for shorts
-Made sure its getting 12v to ECM and Coils in run and start(crank)
Only thing i can think of to test/Replace is cam sensor...
Anyone have some insight or past experiences?
Thanks in advance!!
TECH Junkie
Joined: Dec 2005
Posts: 3,092
Likes: 11
"At key on the pump comes on for 2 sec."
I assume the pump is on while cranking? Are your injectors working? Might need a noid light to check them. There are a number of things in the software that needs to be deleted. Who did your tune?
I assume the pump is on while cranking? Are your injectors working? Might need a noid light to check them. There are a number of things in the software that needs to be deleted. Who did your tune?
Thread Starter
Teching In
Joined: Feb 2013
Posts: 7
Likes: 0
answers to above
The pump is not on while cranking. It comes on for the 2 sec then the only way I get it back on is key off and wait a lil bit.
injector and coils are not getting signal to fire just the constant 12v.
VATS have been deleted. by Brendan from LT1 Swap . com
the crank sensor is light grey for the 58x reluctor wheel
the ecm is E38
this morning I have check the grounds again. everything from the batt to the ecm pins to the block to the coils and injectors have 0 ohms. I found a spot or 2 that had .2 ohms figured that couldnt make a difference.
is there a way to make sure vats are deleted without a scan tool(cant get mine back till next weekend)
still up for suggestion..
The pump is not on while cranking. It comes on for the 2 sec then the only way I get it back on is key off and wait a lil bit.
injector and coils are not getting signal to fire just the constant 12v.
VATS have been deleted. by Brendan from LT1 Swap . com
the crank sensor is light grey for the 58x reluctor wheel
the ecm is E38
this morning I have check the grounds again. everything from the batt to the ecm pins to the block to the coils and injectors have 0 ohms. I found a spot or 2 that had .2 ohms figured that couldnt make a difference.
is there a way to make sure vats are deleted without a scan tool(cant get mine back till next weekend)
still up for suggestion..
Staging Lane
Joined: Mar 2011
Posts: 57
Likes: 0
From: Sioux City, IA
Pull a spark plug out and ground it, then crank motor and check for spark.
If you have no spark it has to be in the wiring, check power and grounds to coils, or crank sensor or wheel.
If you have spark, shoot some brake clean or starter fluid down the throttle body, see if it fires.
Does it show rpm when you crank the motor?
Also if it has not been ran for a while, the injectors might be stuck or clogged.
Get a scan tool and check for dtc codes, and see if all sensors are working.
Also what OS are you running on the E38?
If you have no spark it has to be in the wiring, check power and grounds to coils, or crank sensor or wheel.
If you have spark, shoot some brake clean or starter fluid down the throttle body, see if it fires.
Does it show rpm when you crank the motor?
Also if it has not been ran for a while, the injectors might be stuck or clogged.
Get a scan tool and check for dtc codes, and see if all sensors are working.
Also what OS are you running on the E38?
Last edited by SS409; Sep 21, 2013 at 01:05 PM.
TECH Regular
Joined: Oct 2011
Posts: 408
Likes: 4
Pull a spark plug out and ground it, then crank motor and check for spark.
If you have no spark it has to be in the wiring, check power and grounds to coils, or crank sensor or wheel.
If you have spark, shoot some brake clean or starter fluid down the throttle body, see if it fires.
Does it show rpm when you crank the motor?
Also if it has not been ran for a while, the injectors might be stuck or clogged.
Get a scan tool and check for dtc codes, and see if all sensors are working.
Also what OS are you running on the E38?
If you have no spark it has to be in the wiring, check power and grounds to coils, or crank sensor or wheel.
If you have spark, shoot some brake clean or starter fluid down the throttle body, see if it fires.
Does it show rpm when you crank the motor?
Also if it has not been ran for a while, the injectors might be stuck or clogged.
Get a scan tool and check for dtc codes, and see if all sensors are working.
Also what OS are you running on the E38?
Trending Topics
TECH Junkie
Joined: Dec 2005
Posts: 3,092
Likes: 11
Let us know what you find out. I have a similiar problem with my L92 but mine is ignition. Trying to find out what in the software would cause the motor not to spark. Plenty of things will stop the fuel/injectors/pump. Going to recheck my grounds once again.
By the way are you seeing any RPM(150) or oil pressure when you are cranking the motor. Without oil pressue the ECM my cut off the fuel pump. Plus there are codes that need to be deleted.
By the way are you seeing any RPM(150) or oil pressure when you are cranking the motor. Without oil pressue the ECM my cut off the fuel pump. Plus there are codes that need to be deleted.
Last edited by 1989GTA; Sep 21, 2013 at 04:01 PM.
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Verdad Gallardo Staging Lane
Joined: Mar 2011
Posts: 57
Likes: 0
From: Sioux City, IA
These e38 ecm's are notorious for having vats bypass issues, some OS's require to hookup the starter and powertrain relay wires, some don't.
Do you know what tuner program was used to bypass vats?
Hp tuners has 2 vats disable options, and a starter check disable.
Efi Live has a different vats disable options.
You could try grounding pin 52 and 59 with a 100ohm resitor on the X1 black ecm connector, that is the starter relay wire, and powertrain relay control
Wire info here X1 connector Pin 52 and 59
http://www.lt1swap.com/E38%20ECM%20C...%20Pinouts.htm
Do you know what tuner program was used to bypass vats?
Hp tuners has 2 vats disable options, and a starter check disable.
Efi Live has a different vats disable options.
You could try grounding pin 52 and 59 with a 100ohm resitor on the X1 black ecm connector, that is the starter relay wire, and powertrain relay control
Wire info here X1 connector Pin 52 and 59
http://www.lt1swap.com/E38%20ECM%20C...%20Pinouts.htm
Last edited by SS409; Sep 21, 2013 at 04:16 PM.
Thread Starter
Teching In
Joined: Feb 2013
Posts: 7
Likes: 0
first off I want to say thanks for all the Help!
Im not really sure which one of the thing fixed the issue but after double checking all of the testing that I listed above and switching back to the original crank sensor it fired up. it idles a lil rough but ill work on that. its just nice to hear it after starting the swap a couple months ago. If I were to guess it has something to do with the grounds.. I ohmed all of them connected and then disconnected them and ohmed them again.. maybe one wasnt connected good?? not sure but thank eveyone again!
Im not really sure which one of the thing fixed the issue but after double checking all of the testing that I listed above and switching back to the original crank sensor it fired up. it idles a lil rough but ill work on that. its just nice to hear it after starting the swap a couple months ago. If I were to guess it has something to do with the grounds.. I ohmed all of them connected and then disconnected them and ohmed them again.. maybe one wasnt connected good?? not sure but thank eveyone again!
Staging Lane
Joined: Mar 2011
Posts: 57
Likes: 0
From: Sioux City, IA
It probably was the crank sensor, if it is not working you would have no spark or injectors!
Glad to here you got it running!
It must feel good!
I know it did when I got mine fired up for the first time!
Now you can relax and have a beer!
Glad to here you got it running!
It must feel good!
I know it did when I got mine fired up for the first time!
Now you can relax and have a beer!
Thread Starter
Teching In
Joined: Feb 2013
Posts: 7
Likes: 0
1989 GTA, I dont have a tach hooked up yet. the stock cluster doesnt have one and my is still in the box. as for the oil pressure im not sure yet, I picked up a buddies scan tool a little bit ago.. it doesnt have much read out other than codes I think... but if I find out I will let you know.
another thought maybe all i had to do was scare it with the scan tool.
another thought maybe all i had to do was scare it with the scan tool.
