nonbox

Main Fuel Pump Relay Problem - Symptoms & Cause


I found out I had a Main Fuel Pump Relay Problem when I had these symptoms.

The Symptoms:
Car will crank, and maybe run for a second, then dies quickly, and won't restart on a hot sunny day or after running the heater full blast for a while, and will start fine after cooling for a couple minutes. The condition will get worst over time and then your car won't start.

The Cause:
86-89 Honda main fuel pump relay is prone to failure due to cracked solder. The solder points on the printed circuit board inside the main relay become cracked/loose over time and the heat causes them to expand just enough to break electrical contact. The main relay provides power to the fuel pump.

Here are pics of the Main Fuel Pump Relay:

http://cgi.ebay.com/ebaymotors...85841

Honda Sport

yup, had the same problems/symptoms. replaced my main relay and all was gravy.

Perfectionist

FYI, there are two halves to the relay. One powers the pump, the other the fuel injectors. A code 16 will sometimes show up because of this.