So when I start my recently swapped 2000 civic (with an obd1 b18b1) it seems fine. When the rad fan kicks on the temp gauge shoots to the top and the radio shuts off. When you touch the brake or any climate control or window switch (minus the sunroof) the temp gauge shoots up and the radio turns off.

I have checked my radio and all is good there. I am confused as to what would make this happen? It's like once you put any load on the car the temp gauge goes up, the radio turns off and the dash lights dim.

I would really like some insight here. Obviously it is an electrical problem I just don't really know where to start.


Other tid bits. I painted the engine bay and wire tucked under the fenders (but didn't cut and sodder more than 2 wires).

Thanks guys

 

I'm really not sure if this would do it, but did you mess with any of the grounds in the engine bay or within the car? If you did, then maybe remove them and make sure that they are making good contact. - Jim

 

Definitely a ground problem.

 

I'm guessing you're not allowed to run your ground cable from your battery straight to the motor then?

 

No. why the hell would you do that? the engine itself is a HORRIBLE main ground simply because its isolated because of the RUBBER engine mounts. proper grounding has the battery grounded on the transmission, another ground from the battery to the chassis, and another ground from the valve cover to the radiator support.

at least, that's how I run my grounds and I have never had any ground related issues

 

Yep I fixed my grounds yesterday and everything is back to normal!

 

The engine is the best ground you could have, your engine would not crank otherwise in 999/1000 cars.

However, it is very important to not forget engine to chassis grounds or vis versa. I would start with when this problem first started. Is there a jumper harness installed? etc. Your gauge should not spike like that unless power is bleeding into the sensor connector to the dash. Please inform us as to the condition of the wiring, and what modifications were done, as this is far from stock.