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Discussion Starter #1
I searched but did not find exact issue mentioned.
Yesterday I was checking some things out and found that all 4 fuses for engine management are much lower than everything else.
They're all ~12v when the engine is running, but everything else is ~14v.
So the pcm, maf, coil, icm, injectors, o2 sensors and trans. are all only getting 12v.
Seems odd to me, is this a known issue/problem on a 1994?
These dudes...
 

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Discussion Starter #2
Agh...found the problem.
Ignition switch output 13.9v to aftermarket alarm module.
Coming OUT from the unit is only 12.7v and it fluctuates slightly as well.
@ underhood fuse unit, it's a little lower which would be normal for the length of the wire run.

The installer did a decent job, the loss is from the control module itself.
Ah the joys of aftermarket products:frown2:
 

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Discussion Starter #4
Is the control module grounded properly?

Ken
Yes, it was grounded well.
Less than an ohm when checked to multiple locations.
Even put a jumper on it to test.
Still huge voltage loss so I bypassed the turd and problem solved.
Rock solid 13.6 @ fuses now.

The low voltage would very likely explain some intermittent oddities I could never figure out.
 
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