Lean burn control modules

[prowler]

I 'd like to hear from those who've had the lean burn control module fail and what symptoms you experienced along the way if any. The earlier versions, 76-80 had electrical fail issues, and I know in the 80's they seemed to have sorted them out. I had recently gone through my 77 LeBaron and it has never run better. I don't use the car regularly but do leave it on a battery tender. I drove the car 2 weeks ago and it ran great! Last week I took it to the grocery store and the moment I got on the road, I could tell something was amiss. Flat throttle, very low power and if I tried to accelerate it bogged badly. Made it to the store but on the way home it seemed worse. I had to play with the gas pedal and keep speeds very low. I made a right turn and the engine died out. I coasted to the curb, popped the hood and looked down the carb throat. I thought it was a fuel problem but the entire system was new. A couple of mins later the car fired up but was still no where near correct. Made it home,...barely! It appeared to be in a "limp" mode but still not sure. Car has been in the family since new and have had these modules fail in the past. Last one I got several years ago was from Rock Auto as a reman. I'm still not 100% sure it's the module and am checking fuel press and carb but from what I remember this resembles past module failure. Thanks.....Mike

 

[AMC Diplomat]

I'm still running the lean burn while I build a 360 to replace the whole thing.

If you have a service manual for your year, go through the diagnostic procedures.

There are a lot of things to change/fix before you get to replacing the computer module.

In my case, there was still more wrong even after replacing the computer.

 

[Mikes5thAve]

when my 79 one went it started pinging badly. Like AMC Diplomat said check the service manual, there is a procedure to test them in there that doesn't require any special equipment.
The 80s computers are more reliable, I've never had one fail. But there are more components to it so at some point it ends up being easier to replace it with a normal electronic ignition then chasing down continuous problems.

 

[prowler]

Yes,... there are check procedures for components. But I know from past problems, when you're driving and the engine flat dies out, there's not much that'll do that except the ECM. Since new, probably gone through 5 ECM's including the one on car now. The ECMs are getting a bit more difficult to locate. In the past, a repair company would find the failed electrical component, replace it, and consider the ECM re-maned. There's a couple of companies out their that claim to go through the ECM all the way around and replace or update known components that have a track record of past failures. Of course the price is more as well. Prier to a week ago the car with all the work I'd put into it, had never ran better in the last 25 years.