BTM

i am swapping an ls1 into my 91 240sx, and i have the drivetrain in and in trying to get everything right so the engine can fire, but i am having a weird problem with my coils.

first of all i have a ls1 engine, 99 pcm, and a chase bays engine harness which is meant to be used with the chassis wiring and this year range of pcm i have checked the harness grounds, chassis grounds, and harness pin locations. i have not been able to find anything wrong. i have emailed chasebays about the problem but have not had a response.

with the ignition turned on all 8 coils are drawing power constant. with all 8 coils plugged in there is a 30 amp draw on the pcm power wire. one coil has about 9 amps draw. one bank of coils has about 20 amp draw. the coils get hot to the touch as well as the wires. when i tested for spark while cranking i got nothing.

i thought it could be a bad pcm, but i have no problem communicating with a generic obd2 code reader. i also tried to eliminate the pcm as the problem by using a later model pcm from a 2004 gto. i know there are differences in these pcms, but it shouldnt be a factor in this situation.

i dont really know what could cause this problem so i wanted to get a broad opinion on some forums. any input is appreciated.

BTM

what would also help would be information on how the coils normally work. do they get a constant power supply and constant ground? is the only thing that comtrolls the coils the pcm? i am going to disconnect everything down to the coils and pcm tonight to eliminate other varaibles interfering with this system.

i r teh noobz

iTrader: (4)

I have a couple schematics for an 02 5.3 laying here. Each coil should draw power directly from an ignition fuse (15A per bank, INJ A and INJ B), not from the PCM. They share grounds G104 and G105. Pins 60 and 61 of the PCM are low references for banks one and two, and each coil has a control wire that is switched by the PCM.

Sounds like your coils may be hooked to the PCM power supply, rather than their own fuse.