Hello Im having an issue with my Excursion blowing coils and the #30 fuse. My mechanic seems to think it is the computer but I feel like there is a short of some kind. It has 130,000 miles I have owned it since 2002. Never had any issues. Until last week. I took my daughter to school on my way home it stalled and wouldn't start. Had to have it towed to the mechanic. He found the 30 fuse blown. Picked it up and knew it wasn't right. Took it back and he found the coil blown . Replaced 2 and they kept blowing. He seems to think it might be the computer. Any suggestions? Also it passed smog after the fuse was replaced cause I had to have it done.
Thanks

 

Hmmm...#30 on a gasser comes back as "Radio Noise Capacitor, Coil on Plug, PCM Power Diode"

Stereo acting up at all? A diode if it's in line in a wire is an easy replace...if it's soldered on to a circuit board it's harder...

 

Well the cd player has been acting up for a while now. Saying error. But the Am/Fm has been working. The day it broke down I was listening to it. But would that cause the coils to blow?

 

A Capacitor is basically a storage device for energy...if it is faulty I suppose it could send energy where it shouldn't or in excess of what it should...no idea if that's enough to blow a coil. My question on the coil is - which one? COPs on V10s are known to go due to water coming in from the shroud just at the bottom of the windshield. The "stall/no start" is what I think he's using as a computer issue...just a bad coil would produce a stutter at anything over idle. If it is the PCM that would make sense for your no-start issue...just trying to see if there are any other cheaper things you can check before replacing the PCM.

 

It the #2 coil on the passenger side.

 

Also for some reason the check engine light isn't coming on. But it illuminates when you turn the key. It even passed smog with a blown coil.

 

The CEL at key turn on is normal.
When you say "blown coil" are you getting a misfire feeling?
Misfires have many causes - bad plug, coil, boot, fuel injector, wiring, PCM, etc.
Did you get a code earlier saying it was #2.
Do you have a code reader?
You can get a basic one from Amazon for $12.95 -Oxgord CAN OBD II Scanner Tool that will tell you what cylinder has a misfire when it sets a code and let you clear the code for a retest.
A better setup is available to check for misfires that do not set codes.
Were the coils tested before and after being declared "dead".
They are just a wire wound into a coil (transformer) that has resistance which can be measured.
The input to the coils is 12v which can be measured and the output line goes to the PCM where it is grounded at the appropriate time to fire the plug.
It's difficult to "blow" a coil, the wire will only draw current for the load it creates.
You can't force more current thru it, but high voltage can "blow" it.
The system only has 12-14v normally, but can spike to 17.5v if the alternator voltage regulator is flaky.
Blew out an LCD TV monitor for the kids one time.
There are 12v outlet voltmeters available that are handy for checking system voltage.
The dash gauge in ours is not really useful.