F.AS.T. Injector driver shorted to ground?


Jan 6, 2015
Hi Guys I am having some problems with the new engine startup.
1986 GN
I have a New fast EFI 2.0 and casper box.
I got from Cal back in 2018 and I am just getting this car done so here we go.
I do not have any spark or injector driver output
FAST power light on with key
Casper box standby on with key off? Battery drain?
Casper box key on — standby , 12v power and 5v on.

I started with the no start tree.
Casper box and FAST case are both grounded directly to battery ground terminal.
All grounds that go to block and heads also have a jumper to battery
Pin (P) 12v ign. On (yes) when connected to module and when not connected.
Disconnected 14 pin
IGN. On 12v to Pin. (C) no test light flash
IGN. On ground pin (C) test light flash’s
And triggers fuel pump and injector.
Pin (3) IGN. On has 4.5v continuous?
It appears that the injector driver is shorted
To voltage.
PC connected to ECM shows crank sensor at 150 revolutions when cranking. but still no spark.
Casper box all 3 led light on
FAST key on power on (yes)
Crank flash’s (red) once
Injector flash’s (Amber) once
Anything I am missing here?
System data log?
Data log when attempting to start? Key on, start logging, then crank. A short log may give a clue.
Key on, check for 12v on each inj + harness pin, & ground at each inj - pin.
All six should have 12V on one pin and no ground on the other pin. Then the driver is not shorted.
If you have a NOID lite, will it flash when cranking the engine? The show of rpm shows the crank sensor is working.
Some history....https://www.turbobuick.com/threads/xfi-caspers-adapter-harness-grounding.389885/
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Thanks Chuck
Yes 12v on injectors one side with key on.
Ground the other pin and injectors fire
I have noid light and no flash when cranking.
I will set logging on next attempt.
So I should of added this is a brand new build
And looking at the log I am getting some big draw on the battery? This is with the plugs out , brand new battery, and I used the jump box with it when logging.
Injectors disconnected.
Still no fire and turned off the lights to the shop and the NOID lights had a very faint flash?
I can’t get a good picture that is readable to upload.
0.0 sec.
Map-(kpa) 103
Inj. 0
02 corr. 0%
Air temp 72.0
GPw (ms) 21.1
TPS- 1
Target A/F 12.38
Map (PSIA) 0.2
Actual A/F 15.94
SPARK (BTDC) 26.00

4.80 sec. In.
Inj. 3.5
Battery 11.0v
MAP (PSIA) -0.0
RPM 200s
Nothing else changed from above.

6.3 sec. In
Battery 10.9V
200 RPMs
New batt?
Ground issue??
Check volt drop when cranking. Check + and - sides.
You should have a fully charged batt @ 13+V.
Volt dropping to 10 is no good. 5+V drop is waaay too much.
Get the volt drop fixed first.
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