Ok, I'm thoroughly confused by this one so I'm hoping someone here has run into it before. Yesterday, I was hired to correct an engine swap. It was a 1st gen. b16 into a 90 std. hatch. I've never seen anything that was done as badly as the wiring on this swap. Actually took me over 8 hours to correct everything done wrong (spade connectors, butt connectors that weren't attached, horrible solders, etc.). Anyway, the car had an issue with the lights causing the motor to stall and the brake pedal turning the front blinkers on. I was hoping it was just something they screwed up installing the motor but I didn't find anything.

Basically, if you hit the brakes, the front blinkers illuminate and the motor bogs & dies. If you put it in reverse, the motor bogs and dies. Same thing with the headlights. I also noticed that once the car is started, the fuel gauge drops to empty (I'm not sure as to any other gauges as it wasn't run long enough to get the temp. up and there's no tach in the stock cluster).

I checked all of the wiring I could find and saw no problems. I checked the light switch and it did the same when it was disconnected (I've had a similar problem where this was the cause). Checked the blinker relay in the fuse box and did the same when it was connected. Main relay = same issue. Other relay near main relay & hood release (made by Denso) and it still did it. All of the visible wiring looks fine. I couldn't find anything related in the service manual for trouble shooting. Looking at the wiring diagrams, I see that they're all on the same circuit but I still can't figure it out. Does anyone have any ideas??? I'm thoroughly confused by this one.

 

i can only do so much from the other side of a computer, but those electrical issues are usually caused by feedback through a circuit, because one circuit is grounding through another circuit. so id say your problem is that a wire is not properly grounded and is grounding through another circuit. so i would start with the main grounds and work my way to the individual grounds for the brakelight circuit, etc, checking voltage and continuity.

 

anybody else? I checked all the grounds already. Nobody else has run into this problem before? Does anyone know where the light relay is?