Made my first log and had my truck die on me and then it started raining.

**joegreen** · 07-22-2015

Hello, I have finally been able to get good data. I took my truck out for the first time with the new serial cable installed. About 2 miles from home it just died out of the blue. I figured it was the icm again so i took a wet rag and cooled it down. I was able to get back home by cooling it down then driving then cooling it down then driving. Anyway i have not had the icm tested yet at the store but it is a newish ac delco icm. So i was able to get good data that i would like someone to look at and let me know what i am looking at. I noticed the battery voltage was a little weird and i think i remember we are aiming for a blm of 128. So the file is attached below. Thanks

**sturgillbd** · 07-22-2015

Overall, it is a little rich. Get your ICM issue fixed and you are well on your way to start tuning. Here is a screenshot of the BLM average.
Alternator started charging at approximately 3:56 in the log. Belt slipping ?

Brian

**joegreen** · 07-22-2015

I contacted ac delco to get a replacement icm. Just waiting for them to get back to me.

**joegreen** · 07-22-2015

When i first put on me tbi system i used the ignition module that came with distributor i got off of the donor vehicle. That module eventually failed. Then i bought an ac delco icm and now i am pretty sure that module has failed. Here is my thinking. I used the first icm with the old harness i got off of the donor truck. After that one failed i put on the ac delco icm but still used the old harness. Since then i have replaced the wiring harness with a new one. So the ac delco icm has been used with the old harness and the new one. Do you think that the old harness could have been causing the icm's to fail over a short period of time? Maybe the old harness damaged the ac delco icm and even though it now has a new harness it was just a matter of time before it failed because the old harness damaged it. My distributor does get pretty hot and the thin aluminum plate the icm is screwed to is not much of a heat sink. Do you think heat could be causing these modules to fail. Both times the modules failed was during warm weather. I am just trying to get my truck prepared for the 40 mile commute to school and i dont want to have to worry about the module. Has anyone relocated their icm to like the firewall or something. I have a computer cpu heatsink i was going to use on the bottom of the distributor plate that holds the icm but it still concerns me that the distributor gets so hot from the motor. So basically i am either going to put a heatsink on the underside of the distributor or i am going to relocate the icm to probably the firewall. What would you do or what have you done. Has anyone else had problems with icm's failing. I am always nervous to drive my truck because i never know when it is going to happen again. Thanks

**joegreen** · 07-22-2015

I bought my icm from amazon. So their policy is that they will replace any automotive part for 1 year or if the manufacturer has a longer warranty they use that time frame instead. They are shipping me a new icm as fast as they can so it will be here tomorrow. Then all i do is ship them the old one back on their dime. Not quite as fast as going to the parts store but pretty fast and easy as far as the internet is concerned.

**PJG1173** · 07-22-2015

just making sure here but you are using a liberal coat of grease to help transfer heat to the distributor base right?

**fastacton** · 07-22-2015

Here in central California, it gets plenty hot and I don't have any recurring issues with ICM failures. In my experience, they normally fail soon after installation or they last a good long while. One thing that has seemed to contribute to failure (besides not using thermal grease under the module) is a bad or failing pickup module (I've stopped using used distributors because of this). I don't think you need to relocate the module.

**joegreen** · 07-23-2015

I did apply the thermal compound. I adapted a heat sink from an old computer power supply so i can remote mount the icm. Here is what i have. It came out pretty good and it has more cooling capacity than those other remote mount icm heat sinks with 3 cooling fins.

**joegreen** · 07-23-2015

So i was thinking about the pick up coil. What would it do to the icm if it was bad? Also what about voltage. Could my voltage regulator be bad and sending out to much voltage to the icm.

**fastacton** · 07-23-2015

I don't know for certain that it can harm the ICM, but the ICM can't do it's job properly if it isn't getting a good signal from the pickup. I've seen a bad pickup cause hard starting or no start conditions. I think it's also caused some erratic timing issues.

**joegreen** · 07-27-2015

So with the new remote mount icm heatsink the icm only gets into the low 140f to high 130f range. I am very happy with that temperature. Also the icm is a breeze to change.