ICM? Opti? Ideas?
Burning Brakes
Joined: Nov 2005
Posts: 848
Likes: 1
From: 1992 LT1 6 speed Cayman Islands
The ESC controlls the spark timing. It is a little black box about 2 X 3 inches that is bolted to the side of the AC blower housing on the passenger side.
Look at the FSM for troubleshooting this.
Look at the FSM for troubleshooting this.
Thread Starter
Le Mans Master
Joined: Dec 2000
Posts: 8,740
Likes: 2
From: Minneapolis MN
With spark and fuel I would thin kit would at least try to fire. Is the opti ruled out because I have a new one sitting at my house and could put it in this weekend. Its been the same opti since i bought the car at 64k and for all I know it might be the original.
Safety Car
Joined: Dec 2002
Posts: 3,655
Likes: 24
From: Charleston SC
Since you don’t have FSM here are a few checks that you can do w/o spending a lot of $$$
Buy a spark tester (about $5-$10) and check for proper spark at the coil. If you don’t have good spark here then you will need a FSM to start check coil/ICM and the opti output, high and low res signals.
(The reason for the spark tester is you can set the gap to check for proper spark strength and not just if it is present.)
If you have proper spark at the coil, and the wire from the coil to the opti is good, then check for proper spark at each cylinder using the tester.
The First time my Opti took a dive I had spark at all cylinders using a spark plug but it failed using the tester. If the cap has carbon tacked it will cause the spark to jump all over the place and can still send a weak spark to the plug you are looking at, that is where the tester will show you a problem.
Buy a spark tester (about $5-$10) and check for proper spark at the coil. If you don’t have good spark here then you will need a FSM to start check coil/ICM and the opti output, high and low res signals.
(The reason for the spark tester is you can set the gap to check for proper spark strength and not just if it is present.)
If you have proper spark at the coil, and the wire from the coil to the opti is good, then check for proper spark at each cylinder using the tester.
The First time my Opti took a dive I had spark at all cylinders using a spark plug but it failed using the tester. If the cap has carbon tacked it will cause the spark to jump all over the place and can still send a weak spark to the plug you are looking at, that is where the tester will show you a problem.
Safety Car
Joined: Dec 2002
Posts: 3,655
Likes: 24
From: Charleston SC
Originally Posted by n1kki6
Is their any specific way i can check if its the coild wire? or should i just pick up a cheap generic? The wires are not very old. MSD's.
Thread Starter
Le Mans Master
Joined: Dec 2000
Posts: 8,740
Likes: 2
From: Minneapolis MN
Originally Posted by FD2BLK
Hook the spark tester to the end of the coil wire, whith the other end hooked to the coil, and see if it has spark.
Safety Car
Joined: Dec 2002
Posts: 3,655
Likes: 24
From: Charleston SC
Originally Posted by n1kki6
So if it has spark but its jumping around or not strong then that means it could be the icm. The coil is new.
If it is a strong spark going into the Opti high voltage side and weak spark at the plug and would indicate a bad cap/rotor.
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Thread Starter
Le Mans Master
Joined: Dec 2000
Posts: 8,740
Likes: 2
From: Minneapolis MN
Originally Posted by FD2BLK
If it is weak off the coil it points to the coil/ICM, don't have my FSM in front of me.
If it is a strong spark going into the Opti high voltage side and weak spark at the plug and would indicate a bad cap/rotor.
If it is a strong spark going into the Opti high voltage side and weak spark at the plug and would indicate a bad cap/rotor.
Thread Starter
Le Mans Master
Joined: Dec 2000
Posts: 8,740
Likes: 2
From: Minneapolis MN
Which one of these do I need.
http://www.napaonline.com/MasterPage...ster&VehCode=N
http://www.napaonline.com/MasterPage...ment&VehCode=N
http://www.napaonline.com/MasterPage...ster&VehCode=N
http://www.napaonline.com/MasterPage...ment&VehCode=N
Safety Car
Joined: Dec 2002
Posts: 3,655
Likes: 24
From: Charleston SC
I have one similar to this one, it allows you to adjust the gap on the tester for your ignition, I used HEI settings. Bought mine at auto zone
http://store.yahoo.com/joeztools/igspartes.html
http://store.yahoo.com/joeztools/igspartes.html
Safety Car
Joined: Feb 1999
Posts: 3,504
Likes: 4
From: Mexico Beach FL
Even though you "think" you are getting fuel, do yourself a favor and buy an injector noid light for GM at the local auto store -- it isn't expensive.
Pull one of the injector plugs and plug it into the noid light, crank the engine and watch the light -- it should flash.
If the light doesn't flash, you aren't injecting fuel.
Tom Piper
Pull one of the injector plugs and plug it into the noid light, crank the engine and watch the light -- it should flash.
If the light doesn't flash, you aren't injecting fuel.
Tom Piper
Thread Starter
Le Mans Master
Joined: Dec 2000
Posts: 8,740
Likes: 2
From: Minneapolis MN
Originally Posted by FD2BLK
I have one similar to this one, it allows you to adjust the gap on the tester for your ignition, I used HEI settings. Bought mine at auto zone
http://store.yahoo.com/joeztools/igspartes.html
http://store.yahoo.com/joeztools/igspartes.html
Drifting
Joined: Sep 2003
Posts: 1,483
Likes: 4
From: middle TN
I hear ya. So much other crap to check, methods to learn, and tools to buy, I wonder if it wouldn't be easier to just do the opti first, since that's the likely culprit anyway.
My 94's sitting in the garage just waiting for me to order a Dynaspark. And I'm gonna, here in about two weeks when I get the time.
My 94's sitting in the garage just waiting for me to order a Dynaspark. And I'm gonna, here in about two weeks when I get the time.
Safety Car
Joined: Dec 2002
Posts: 3,655
Likes: 24
From: Charleston SC
Originally Posted by n1kki6
So how will that tell me if the spark is strong enough. Just by looking at it to see if it bridges or something. What do I set the gap to. Are we talking spark plug gap?
