I have been reading a lot of post about issues with the ECU in my 1981. I bought my PROJECT as a non-runner even though I have put some donuts in the yard against the wives wishes. However while it starts almost instantly every time it is clearly by smell and idle running very rich and idles at 1100 RPM. I have been rebuilding the suspension but got bored and started with cleaning up under the hood now. Most of the wires under the hood are roached/rotten out so I have been doing a controlled clean out of them. Same goes for the vacuum lines that had all been dry rotted. In the long run I want to put in electric lifts on the lights and do away with as much electrical and vacuum systems as possible or upgrade to modern. The carb is now an Edelbrock 1406 600cfm, smog and A/C are gone as well (may add A/C back one day in some form). The distributor is still factory original and I am not sure how that is working correctly as far as advance is concerned. The TH350 transmission is still there as well for now and foreseeable near future. My goal with this project is just a cruiser that will see a lot of highway miles but not a track at all.

So that said can I just remove the "computers"? In fact the car was flooded at one point and I think there is more rust than micro chips in them anyway. Any other suggestions and tips would be greatly appreciated and feel free to come wrench if your in Virginia. ^_^

 

You have to replace the distributor unless it has already been replaced with a non-ECM type. Have you opened it up to see if there are advance weights and springs? How is the lock up feature of the torque converter being controlled?

 

No idea on the lockup, prolly not happening. The car hasn't seen the road sense buying it and it sat in a backyard for the 10 years before that without running. I didn't think to open up the distributor, the wires and outside of it are all factory original.

 

Without the Carb, the computer (if it is working at all) will go into a "limp home" mode since it is getting no inputs from the throttle position sensor. If it is in the "limp home" mode there will be no spark advance or trans lockup. Without any spark advance it will be way down on power.

So you need to go to an older distributor with a vacuum advance. OR you can go find an E4ME computer controlled carb and see if you can get the computer running again. (Challenge!)

I suppose you are not getting a Check Engine Light -- probably removed the bulb when the carb was changed.

 

on the 81 year and that year only the cpu controls the carb idle mixture at idle only, it takes almost exclusive control of the air fuel ratio when the throttle is in the idle postion regardless of rpm or any other thing. the only other thing the 81 cpu does is control the the torque converter and ive heard that a 5 speed transmission was also controlled but ive never seen or worked with that
what wajulia said is spot on, it will also idle like crap.

 

your computer is not working .your high idle maybe from a vac leak.you need a new distributer .speed way has one that is plug and play with coil for 70.00.now check to see what tranny you have to find out if you need a lock up.

 

If your up for the challenge mentioned by wajulia, I am doing a body-off LS swap to my '81 and have the carb and ecu available along with a Computer Command Control supplement manual. Hit me up if you're interested for details.

 

Thank you guys I appreciate the info and offer. I want to get away from the GM computer I think I will look into the speed way distributer suggested.

 

That 74-80 HEI is cheap and everywhere, but first check your distributor. If it has weights and springs the computer can't eff with it. If not it will have 7 pins on the module instead of the usual 4. That computer controlled carb worked SO WELL that they gave up on it after 1 year. The computer needs to go where the carb went. It is lonely with no one to talk to..

 

Does your dist have a vacuum advance?

 

No, the dist on the car now is the factory original for 81, with computer controlled advance.

 

Then it has no advance. No throttle pos sensor, so it has no idea if you are at idle or full throttle.

 

the 81 was the first year with the e4me carb, it has tps, idle air sensors mounted right on carb. its a pain in the *** to "tune" requires a vac gauge and dwell meter and voltmeter to get it within cpu paramaters after a rebuild/replacement. that said it works well but starting 82 they used a newer cpu to control more and introduced more features. so the issue really lies in that this is a one year only application therefore most of us who can tune a holley blindfolded are stuck trying to make the cpu happy.

 

I went ahead and ordered a new distributor with vacuum advance to replace the one on the car now. Also looked around more and found the electronic choke didn't have a positive lead to it just ground and a vacuum hose on the back of the intake manifold was completely dry rooted and open to air. I'll fix those issue and try the new distributor and see where I am at. Thank you for all the suggestions, any other tips or idea to make the car more highway friendly?