modified 502mpi intake on 502 dyno session at my shop
05-02-2016 | 03:21 PM
#191
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From: frankenmuth michigan
Pulse width/square wave is identical on a 2 channel meter/oscilliscope, voltage on both batches is within a 1/100 th of a volt even under a load, ie 6.08/6.09 acrossed both batches at furthest a/b batch injectors from ecu and power supply, voltage at those injectors is 12.8 on both on supply side at 3000 rpms/wot.
Last edited by articfriends; 05-02-2016 at 03:25 PM.
05-02-2016 | 03:27 PM
#192
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From: frankenmuth michigan
And as far as injector time on/off, there is no adjustment between batches in programming. Again, does this w 2 diff harnesses and 2 diff ecu's that have previously worked on other stuff
05-02-2016 | 03:29 PM
#193
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From: St. Pete Beach, FL
Pulse width/square wave is identical on a 2 channel meter/oscilliscope, voltage on both batches is within a 1/100 th of a volt even under a load, ie 6.08/6.09 acrossed both batches at furthest a/b batch injectors from ecu and power supply, voltage at those injectors is 12.8 on both on supply side at 3000 rpms/wot.
What is the driver arrangement in the ECM? 8? 2? 1?
Some injector coil winding failures don't manifest themselves until the thing is warm.
Is this with the pro charger?
05-02-2016 | 03:39 PM
#194
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From: frankenmuth michigan
1467 and 2358, NA, no procharger, back probed new harness thru injectors hot and got same numbers BUT did not put ohm meter on each injector hot yet, ran out of time before this stupid trip on to Fla
05-02-2016 | 03:43 PM
#195
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Only thing left to try is to swap every lead on both batches and see IF problem switches to opposite bank on all four, if it DOESNT then 1 of the injectors under manifold is somehow shorting to ground but NOT showing on any test done so far
05-02-2016 | 03:43 PM
#196
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From: St. Pete Beach, FL
Pulse width/square wave is identical on a 2 channel meter/oscilliscope, voltage on both batches is within a 1/100 th of a volt even under a load, ie 6.08/6.09 acrossed both batches at furthest a/b batch injectors from ecu and power supply, voltage at those injectors is 12.8 on both on supply side at 3000 rpms/wot.
05-02-2016 | 07:31 PM
#198
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From: frankenmuth michigan
The "vortech, crockett, azsm etc" square version is better than the kn w/ round adapter but no where close to the ugly stock one used on gen Vs
05-02-2016 | 07:34 PM
#199
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From: frankenmuth michigan
05-03-2016 | 06:04 AM
#200
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From: taxachusetts
In florida now till wed BUT did swap harness and redo grounds friday and make some pulls. Problem remains same, have just about tried everything. When i say "bank", i really meant "batch". To re-iterate, i can pull motor to 3000 or 3500, hold it on dyno brake at wot, #1 cylinder will be at 10.5, #3 will be at 14.5, #5 will be at 14.5, #7 will be at 10.5 (give or take a tiny bit). Then,switch injector lead from # 1 to 3, 3 to 1 ( both on different batches), do same for #5 and#7 (both diff batches). Make same pull, now#1 will be mid 14's, 3 will be mid 10's, 5 will be mid 10's and 7 will be mid 14's. It definatly follows the batch wiring which rules out anything mechanical, air distribution, fuel supply etc.
Now that i swapped harnesses, ecu (injector drivers), watched injector pulse wave form and supply side voltage from both batches on dual channel oscilloscope under a load theres not much left. The only other thing i thought of since friday is to swap ALL the injector leads batch to batch and see if problem follows from batch to batch on all 8 cylinders.
Now that i swapped harnesses, ecu (injector drivers), watched injector pulse wave form and supply side voltage from both batches on dual channel oscilloscope under a load theres not much left. The only other thing i thought of since friday is to swap ALL the injector leads batch to batch and see if problem follows from batch to batch on all 8 cylinders.
