1988 SE, S4 NA
Bone Stock

Any who so heres the list of quirks and questions I have

1. Upon cold starting, the idle surges between about 1k and 1500 as if someone is goosing the throttle. Whats up with that? Not the cold start assist but just surging. Goes away after its completely warmed up but until then if I have the clutch pedal in or in neutral, I get the comical surging

2. Clock and Idiot Cluster. Intermittently works and doesnt work. Seat belt light comes on intermittently as does the hatch open light. Trust me the hatch is alllll that way closed. Seems to happen under hard braking, acceleration and turning. Broken cold solder joints?

3. Radio lights up but make static. Antennae comes up most of the way and goes down most of the way. What is keeping the radio from picking up fm frequencies?

Is there anyway to repair the oem radio? back lights come on but nothing displays.

4. Brake lights aren't working at all. I bought a new brake light switch to throw at it, but I haven't gotten down and dirty with the DMM yet. Any common problems I should look out for?

 

Most of that sounds like bad grounds or opens in the system. (Opener being the solder joints) More experienced guys may be able to tell you where.

 

I have 1987 FC3S 13B

When I bought it, it had a newer radio installed the previous owner told me he had to replace the OEM cause it just not worth the head ache to repair. He had broken the center console try to find out what caused the same thing you described.

The first issue I fixed was the 7.5 fuse in internal Fuse box but even after I replace the antenna was not coming up but I the display on radio show it should be.

I unhooked the wiring and then tidied up the wiring (a rats nest mess) then it worked. Think it was a faulting connect caused by the ground and wires cut to short to make clean connection.

I'm still try to trouble shoot it because it only worked for about a week then stopped raising, might break down and replace motor and wiring to it cuz the Fuzz and buzz must be fixed.

 

i just got my FD3S and it had similar electrical problems
just went away with replacing all the fuses

 

at least for my FD when cold start it starts idling a little low like 750-800 then when it warms up it idles about 1000-1200

 

1: set the TPS.
2: cold solder joints.the Idiot cluster is known for that.
3:..are you still using a rotary dial phone TOO?..
get rid if that 25 year old radio!..lol!.I can sell you 8 track tapes if you are sentimental!
.No,seriously,if you are capable with electronics it will be easy,If not Guys are tossing those radios out all the time and can be had cheaply in the FS Classifieds.
Power antenna:..plastic track probably broken..YAY..(REPLACE that too.).
I got a rubber ducky antenna and tossed that on..Got it at Walmart.works good.