sputtering isssue
Team Owner
Joined: Sep 2005
Posts: 20,352
Likes: 568
From: Ventura County, Calif
Yes, this is the right place. I'll just repost for you to get you started. Good luck again. 
I bought a c4 10/0/2010. Replaced opti, icm, coil, plugs, wires and even maf sensor. Starting after full install had code for faulty brand new icm. Replaced, and car ran nice and strong. Since full ignition replacement, I had to replace the icm 2 more times. Every three months the icm has gone bad so went with gm icm. Now 7/20/2011 I am having the same sputtering issues but this time I finally formally checked the icm, and using All Data flow chart-no codes were present- the module from gm checked ok. I also had it checked at Advance Auto. Wires are seperate from engine contract, through logic probe tested consistent pulse from opti-low res and high res signal to ecm, pulse from ecm to module, and pulse from icm to coil. All consistent when engine sputtered under (hot sputtering) condition. I checked fuel pressure also under hot condition, fuel pressure 35 to 45 under load, 45 to 40 koeo. need help to fig out problem.
Burning Brakes
Joined: Feb 2009
Posts: 785
Likes: 3
From: Richmond Virginia
Not sure what year you have (always a good idea to fill out your profile)
Since you mentioned opti-we're talking LT1/4. If you've been using thermal grease (a good thing) on the backside of your multiple ICM failures. You may have a possible coil breaking down when hot, weak ign. coils can cause the ICM to have a short life.
Just caught your other post--a '94
Since you mentioned opti-we're talking LT1/4. If you've been using thermal grease (a good thing) on the backside of your multiple ICM failures. You may have a possible coil breaking down when hot, weak ign. coils can cause the ICM to have a short life.
Just caught your other post--a '94
Last edited by TWISTERUP; Jul 21, 2011 at 08:53 PM.
Thread Starter
Intermediate
Joined: Jul 2011
Posts: 30
Likes: 0
Its a 94 vette. I used the grease the second time, then I moved icm to inner rf tire well by lengthening and soldering the wires 1 gauge larger for distance, and putting a 1" spacer between icm and wall. It ran very good with temperature to touch for 1.5 mos till now. Also new coil. Everyhting is 6k miles old.
Last edited by marcwb; Jul 21, 2011 at 09:00 PM. Reason: extra info
