[jahson]

I have a 1994 honda civic and when it rains my fuel pump takes long to chip in engine check light stays on in dash and when the pump finally trips in it goes out then I can start the car someone help with this:mad:

[Duane in Japan]

Your english is a little fuzzy friend but I think I understand what you are saying. The Main Relay controls power to the ECU which controls the ground circuits for the CEL and the fuel pump when you first turn the key on. After the first few seconds, the ECU is supposed to release these grounds turning off the CEL and the fuel pump. Then in the crank mode and the run mode, the ECU tells the Main Relay to power the fuel pump all the time.

Main Relays are a major problem with Hondas and ECUs are pretty reliable, but the ground for the ECU is many times on the thermostat housing and it needs cleaned up sometimes.

It is possible that the switch in the relay is burnt and visually would look something like velcro, the two halves of the switch may stick together longer than normal, but I don't think both switches in the Main Relay would go bac at the same time.

Clean the main ground and change the Main Relay as a matter of course, preventive maintenance.

[TxGreaseMonkey]

. Clean the main ECM ground, on the thermostat housing, and apply dielectric grease.

. Test the ECM, by performing the K-Test. Many CEL problems originate from problems with the ECM.

The K-Test: Remove the MAP Sensor connector and turn the ignition switch to ON (not start). Using a multimeter, check for 5 volts going between the MAP Sensor connector's reference wire (+) and ground. As you look at the connector, this is the socket on the right. Really press the black test lead into a cleaned main ECM ground on the thermostat housing. If the voltage is low, it's probably indicating ECM failure. Most failed ECMs will record a fraction of a volt.

. This section may help you, particularly Item 11:

https://www.askmehelpdesk.com/cars-t...tml#post219991