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Noid light on, then flashing - what does it mean?

  • Thread starter Thread starter DREDD_LX93
  • Start date Start date Mar 14, 2010
D

DREDD_LX93

New Member
Mar 1, 2010
39
0
0
Mar 14, 2010
#1
  • Mar 14, 2010
  • #1
Hey guys, so I'm trying to get my non-starting Mustang to finally start.

I was testing the injectors with a noid light, and noticed the following:

When I turn the key in the ignition to on, the noid light turns on and stays that way.
Then, when I turn the distributor, the noid light flashes.

Now, I've read that while you're trying to start the car, if the noid light stays on or stays off, there's an electrical problem, but if it flashes, it's ok.

My noid light seems to be doing both, so I'm confused. What could this symptom indicate?

I've verified that there's fuel at the injectors cuz I removed the #1 spark plug to check for spark and it was wet with fuel.

Please let me know what you think it might be.

Thanks!
 
S

stangbang302

New Member
Jul 13, 2007
180
0
0
fort valley, ga
Mar 14, 2010
#2
  • Mar 14, 2010
  • #2
you turn the key to on, so you'll get a hot wire and it'll be constant, when the car cranks, the injectors pulse, so the flashing is pulsing, and the light staying on is turning accessories on.
 

BlownFiveLiter

have car, will race....wait, it doesn't run
15 Year Member
Nov 29, 1999
3,133
18
108
Chicagoland
Mar 14, 2010
#3
  • Mar 14, 2010
  • #3
It should do that. The injectors are always hot when the ignition is on, like stangbang302 said. They're grounded through the EEC and pulse that way, so the flashing you see is injector pulsing.
 

liljoe07

5 Year Member
Feb 18, 2009
1,622
363
124
Cartersville,Ga
Mar 14, 2010
#4
  • Mar 14, 2010
  • #4
Noid light should not be lit with just a key on. If that's the case, the the ECM is opening the injectors. They should only open when the ECM recieves a PIP signal(cranking)
 
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