1998 honda civic will start in the morning but after you drive for a while and shut it off it will not start for up to a half hour or sometimes longer. i have heard that the alarm will cause this problem. if somebody has delt with this problem before please help. the fuel pump has been changed. the battery is new and the alternator is good. no idea what else could be causing this. would really appreciate the help thanks in advance!!!!!!!!!!!!

 

When the engine won't start:

1) Turn the key to ON(II). Do you hear the low humming noise of the fuel pump priming for seconds?

2) Check whether there is bright bluish rather than weak orangish spark at the plugs.

 

no the fuel pump is not turning on i m sure of that the car has been sitting for 2 hours and nothing the fuel pump will not kick on

 

Sounds like a classic case of a bad main relay, which supplies power to the fuel pump. If you have a multimeter, I can post a diagram that details how to test whether the main relay is bad. Otherwise, you could try buying a new one, and hope it fixes the problem. It's a risk because there are other possible causes, such as a faulty fuel pump.

In addition, check whether or not you have spark.

 

yes i have a multi meter if u could post that that would be very helpfull i am not very good with electrical problems so any extra info explaining what to do would be appreciated

 

To access the main relay, remove the two lower bolts securing the glove box and then remove it. The main relay is on the right side of the glove box. In addition to the multimeter, you also need some wires to connect battery terminals to the main relay. Post any questions that arise.

 

Thank you for the advice. That was the problem. Now we still just have one issue. The car is idling low but sometimes it idles right. Is there any way to check the idle control sensor? Or do you just have to buy another one? Thank you so much for all of your help.

 

This is usually the idle air control valve (or EACV) sticking. Remove the idle air control valve and clean the air passages with spray carb or throttle body cleaner. I think on a '98 the valve is mounted on the back of the throttle body.

 

Thank you we will give that a try.

 

We think that we found the idle air control valve under the air filter. The thing is we havent changed the fuel filter yet and someone seems to think that will fix the problem without having to remove the air filter. Would that have any affect on the idle? Thank you for all of your help.