I installed a new BBK throttle body on my 85 today and while going thru the IAC, Timing and Idle procedures, an issue with my dash cluster arose. The thing was flickering / pulsating like crazy! All the numbers were wildly changing, the bar graphs going up and down. Everything was fine when I started the car for the first time to do the timing. Once I was done setting the correct timing and I went to put the car back into Park did I see the dash behaving like this. It only does this when the car is running though, with the key in just the on position, the dash lights as it should giving correct read outs. As soon as the car starts, all goes nuts. The car runs and drives great even though the dash is having its own dance party. I rebuild the cluster last year and its been trouble free since. Is there a ground behind the distributor that could of been disturbed when I rotated the distributor for the timing adjustment?

Last week, the Brake light in the DIC wasn't illuminated and the parking brake was clearly on. Today, that light was working as it should be, but there was no Check Engine light when the key was first turned to the on position. Could the DIC be causing this problem? Bad ECM?

Anyone experience this? Any input is appreciated. I've attached a video so you can see what I'm talking about.

 

I've been trying to find out what is going on, checking grounds, harnesses, etc. I noticed something interesting. With the car running and the cluster going all erratic, if I put the directionals on, the cluster even outs some. It's not perfect, but it's at least legible. The numbers stabilize but the 2 bar graphs are still not what they should be.

 

Read to get ahold of batee.com, e rebuilds, fixes these for fair $. Sometimes the solder joints go bad and need to be redone, these cars shake themselves to death it seems.
Have you tried checking for codes by jumping the two terminals on the obd port? Do you see the security light come on when you put the key in?

 

I actually emailed Batee.com and got a response. Bryan suggested checking the plug wires and alternator. The security light does flash but I don’t check a Check Engine light with the key in the On position. Last week, the Check Engine was there in the On position but the Brake light was off (the parking brake was on so that light should of been on too). That light works now. SMH

 

UPDATE - after inspecting the wires to the distributor, I found out it was the tach wire going to the coil at the distributor cap causing the issue. It appears to be part of a makeshift repair by a PO after tracing the path of the wire. All is well at this point and the dash is stable. I'll remove the wiper motor and rewire that connection to avoid future problems.

Now to figure out why there is no Check Engine light, hoping it's just circuit board on the Information Center or a burnt bulb.

 

im having the same situation. replaced all the bulbs in the dash and all was great for a month. pulled the car out of the garage today, since it was nice outside, and the dash seemed like it didnt want to light up. not really flickering, but going in and out at random.

i did just have the valve cover gaskets replaced, so ill have to check the wiring under the hood

 

Did you notice the two circuit boards? Those that are connected by a line of copper wires? Resolder those connections. They are known to get brittle and cause your flickering