power issues along with speedo.

89 coupe hud.

Okay, recently the car has started to bog out of no where and when it really starts to bog it stutters and dies out. and i completely lose power to everything, i got the battery tested and it works fine. when this happens all i need is a boost and the car starts to run again. but now it doesn’t it gets worst, so i take it the terminals are bad. so i’m going to go to crappy tire tomorrow and grab new terminals for the battery.

question is while i’m at it, where are all the grounds located, or key grounds, i only see one from the battery to the chassis. can someone please fill me in on other locations.

and 2nd problem.
my speedo doesn’t work, the hud and the cluster displays 0. i can rev fine when the car is actually running normally but i’m not getting a reading of how fast i’m going. i just picked up a parts car and i tried using the dohc speed sensor and still no dice. so i’m wondering what should i do to fix this issue.

also would these two issues be related? as in, if i fix the grounding issues and the terminal points would/could the speedo be effected by it?

tia. tried searching, but SON keywords are bitch to use.

What motor are you running?

Get your battery tested when you goto CT.