lt4 has no spark....
On The Tree
Joined: Aug 2009
Posts: 137
Likes: 0
From: Burbank, Ca
This same thing happened to me I did long tubes and when i put everything back together no spark.... So i started with the basics, new opti, coil, ICM, plugs wires and all that. Checked for fuel, re did all the grounds still nothing!!! I was at the end of the rope cause the car was done for a month! When i put the headers in some how i had cooked the wire in the ICM or moved it out if the way. And the wiring harness was so old and brittle it broke. there is a wire in there that runs from the ICM to the coil and that is what gives power. Belive it is the pink wire (i have a 97 Z) use a test light and check all the plugs for brittle loose connections.. hopefully that will do the trick for ya.
On The Tree
Joined: Aug 2009
Posts: 137
Likes: 0
From: Burbank, Ca
hbh racing makes a "LT1 No start dignostic step by step" write up. it has everything you need to get the car running. basically it will narrow it done to the opti, icm, computer or what ever. On mine it keep saying that it was the icm and i replaced it several times problem was the power wasnt leaving the ICM due the the harness. if you cant find the link let me know.
Thread Starter
On The Tree
Joined: Feb 2008
Posts: 146
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i have cheked my power w/ a test light and it results that the connector that goes connected to the blaster is giving me a very weak sign of power.....could it be that i have a bad ground or should i replace that connector??????
On The Tree
Joined: Aug 2009
Posts: 137
Likes: 0
From: Burbank, Ca
from the ICM? thats how we found the problem on mine starting with the injectors. charge the battery and get a voltage reader and find out how much juice should be coming out and go from there.... pull the loom on the wires and chech to see if there brittle. Also mtn Dew can clean all the corrosion off those plugs
