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Discussion Starter #1
my intermitten stalling problem has finally became crank no start DONT THINK ITS THE OPTI .
there is no power at coil or icm with key on .
I used a test light the ignition fuse was blown.
I replaced it but still no power at coil or Icm
 

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Please state year of your car as there are differences between 93-97 lt1 cars.

You can get 93, 94, 95, & 96 service manuals at the following link. You will need to find all the circuits that serve fuse that is blowing. And see if coil & icm use that fuse or another. You are going to have to find where the short is. My Files
 

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Discussion Starter #4 (Edited)
I have the same ones missing the 6E trouble shooting parts Doesnt tell how to find short just how to throw parts at it
coil icm crank sensor its tied in too
on the low resalution line.
kind of chasing my tale here
my intermitten stalling problem has finally became crank no start DONT THINK ITS THE OPTI .
there is no power at coil or icm with key on .
I used a test light the ignition fuse was blown.
I replaced it but still no power at coil or Icm
got power back after blowing another 10 amp fuse
ohm tested coil 810 on all three terminals
but no power at coil wire with key on not even while cranking
any help would be greatly appreciated
 

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Route from ignition fuse involves the following splices & connectors; Power leaves fuse on pink wire goes through connector C100 cavity G. it then goes through splice S107. There wire forms 2 pink wires. 1st wire goes to coil connector C2 cavity A. The other pink wire goes to crankshaft position sensor.

You need to test pink wire with key on at C100. See if there's power at both sides of C100. If no, short is between fuse and connector C100. If yes, test at splice S107. If splice has power, short is between splice 107 and coil.

Also if fuse has no power, short is between electrical part of ignition switch and fuse. elec part of ign sw is under the dash & bolted to steering column.

C100 is found on right side inner wheel well. S107 is in engine wire harness about 2 & 1/2 inches from # 3 fuel injector wire breakout.
 

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Discussion Starter #6
both the coil and icm i think are over do so Im picking up a accel coil and delphi icm
should take care of it .
their 22 years old
Not as pricy as sensors
I got this thanks
 

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If you have no power to coil, then new coil & icm are not likely to fix problem, unless one of them is shorted out..Do the tests I outline below & let us know the results when you install the parts.

If coil icm, or crankshaft position sensor (CPS) is shorted & giving you no power at coil, remove the connectors of coil/icm & CPS. With key on, use your multimeter set to dc volts and see if you have battery voltage on pink wire @ coil connector. If you now have battery voltage with connectors off, & you had no power with connectors hooked up, then coil, icm, or CPS is shorted.
 

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Discussion Starter #8
So lost
I replaced the coil, icm, and cps and the car ran then today it all went hay wire and started blowing the 20 amp ignition fuse .
before it was the ten amp.
and now with opti unplugged icm unplugged cps unplugged I try to plug in coil and it blows the 20 amp fuse .
tryed it with old coil blows the 20 amp fuse too.
with them all unplugged and a good fuse I do have 12 volts or so on pink wire on both icm and coil plug.
Also I was using spectra opti harness and it might have fried something
I think the crank sensor was abstructed when I pulled it ,It had collected a pile of steel on magnet
So I am lost at where to go next?
 

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Opti gets it's 12 volt power from PCM. So if it were shorted it would not blow ignition fuse. Coil, icm, & cps share the same fuse for power source.

Start by having all 3 disconnected. With ign on, see if 10 amp ign fuse blows. If no, plug in cps. Does fuse blow with ign on? If yes, short in cps wiring. If no, unplug cps. Use a jumper wire to just plug coil in. Does fuse blow? If yes, wire to coil is shorted. If no, unplug coil & use jumper to power icm. Does fuse blow? If yes wire to icm shorted.

The other, larger amp ignition fuse is the pcm, fuel pump relay, & fuel pump power.
 

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Discussion Starter #10
my hot wires are showing grounds on logic probe .
with key off every thing unplugged still pink wires on coil and icm show green for ground .
All four pins on unplugged opti are glowing green too .
I dropped the starter yesterday to get 8th spark plug I didnt unhook wires but I bet I have a hot down there touching frame.
so Ill get backto you when Ive dropped the starter.
Just retracing my steps.
 

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Discussion Starter #11
After puting the starter back in they started lighting up red and green hooked
them up and not blowing 20 amp any more and the car starts .
so i think Im back to the first problem but I have to test drive it Ill let you know
 

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Discussion Starter #12
I think its fixed for now any way I smelled gas at first and it hasnt let me thottle it up in months.
But it let me unload through the gears all the way around block so im driving it to work tomorrow'
And keeping my fingers crossed.
New tune up definately made a improvement.
I checked the codes and all it had was a p100
all though I kept jumping it and disconnecting the battery.
have to get it through a day to be sure .
thanks again for the help Coco.
 

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Discussion Starter #13
The car went nuts.
It broke down right as I hit my driveway and all of a sudden all the breakers were clicking and the air pump was going on and off.
I unplugged the air pump and tried to start it .
The relays went crazy and it just cranked .
I checked the codes and it said
p100 p102 p160 p300 p372 p1351 p1371 p1441
I plugged the airpump back in and it fired right back up about a hour later and was fine
about a hour later How weird is that?
 

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Older cars can have some pretty strange electrical symptoms. Maybe it's time to hire a witch doctor to excise the evil spirits residing in your car.

But seriously, your latest round of symptoms sound like a major intermittent power outage from a bad connection. You will need to consult the power distribution & ground distribution wiring diagrams in the 97 service manual.

The positive battery terminal has wires going to starter, alternator, & junction box on passenger side inner front fender well. From junction box there are 7 fusible links that give live , all the time power, to various relays, both fuse boxes, electrical part of ignition switch, & headlight switch.

Your problem is probably an intermittent bad connection. It could be as simple as bad connection Of + battery cable at either end. Or bad - cable at either end. Or bad connection at any one of the fusible links. A fusible link can have broken wires inside that lose connection as wire wiggles going down the road.

Also bad connection can com from end of wire that goes to relays, fuse boxes, or electrical part of ign sw. So get your wiring diagrams out and start looking.

I didn't delve too deep into the ground circuits. But they can cause mischief also. Lastly, old corroded wire can cause symptoms.
 

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Discussion Starter #15
Help please , I got shocked LOL
I thought I new what a plain old circuit was.
I had the ground on battery disconected
the ignition unplugged at the switch on the collum and
and the positive junction box on fender with fusible links taken apart to check them individually
and was getting out of my car and touched under the door panel and got shocked LOL.
id been getting shocked like that since I owned the car .
Every one said it was static electricity.
I started probing maf plug and all unconnected
fuse links even unplugged maf censer fuse. and got 7 volts on both sides with fuse out
I thought no way.
I probed the negative battery cable bolt on fender positive 7 volts
I probed the alternator bracket got positive 7 volts .
I unbolted and disconnected positive battery cable of alternator
and all grounds and all wires went dead .
Gocha LOL
At least I think the short is the alternator.
If any one would confirm it before I buy another alternator It would greatly be apreciated
I still cant figure out how it was making a circuit with the negative off the battery
Exept through a jack stand lol
 

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Take your alternator to an auto parts store for testing. For DC voltage to flow, it must make a complete circuit from battery and back to battery. With negative battery terminal disconnected, if voltage flows, the laws of physics are being violated.
 

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Discussion Starter #17
I think that witch doctor has been hanging around.
totally weird.
The alternator was making 14.5 volts when it went down and battery was staying charged.
The field diode or regulater in the alternator must be why its got continuity from positive to negative body ground.
Its a realy huge alternator Im used to 35 and 60 amp and this is a little early at 107000 miles for brushes
I actually want to see if a insulator or shield of some kind is out of place.
and yet theyll still keep running if you pull a post off of battery .
and also the battery was holding power with the key off.
the field capaciter has to be leaking from its skin or some thing and jumping the gap .
When I was in high school electronics and one time I picked up a charged capacitor at one end
and zapped the heck out of myself ,kind of a prank that back fired lol
I think it broke the physics law back then to.
They might have designed the capacitor to big to make that 140 amps or what ever..
the bigger armature might be wearing brushes out early.
Im going to crack it open and check it out.
see if I can rebuild it for a spare if its brushes and I can find them
I have to put the ignition switch back on the steering collumn in and figure out how that cable attaches.
Cause I forgot how it attaches .And a new alternator. .
And I think Im up and running again.
Ill let you know THANKS COCOA BOLO
 

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Discussion Starter #18
Wasnt it back to the drawing board.the probe was grounding the short circuit
I know Im missing a grommet going through the fire wall .
 
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