[&:]Hey Folks,I am very interested in getting some help for my problem.I have a 91 Accord.The fuel pump will only turn on about half the time.When the pump turns on I can hear it and the car will start right up.When I dont hear it the car will not start.I have replaced the main relay and it did not help.Once the car is started,the is no slugish performance which leads me to believe that the pump is fine but,Im not sure.Why would the pump turn on only half the time???

 

I do not think that you can assume that the fuel pump is working properly.

You need to determine if the fuel pump is getting power from the main fuel relay.

There is a three pin connector in the trunk with a blk/yel wire going to the fuel sending unit (there is a metal cover over the sending unit). The blk/yel wire will have 12V for two seconds when you turn the key to the II position. Backprobe the blk/yel wire with a pin and measure the voltage to ground using a volt meter.

Also check that the ground near there is clean and it bolted down securly.

 

Hello Again,I have tested the sending unit wires and it (does) get power when the pump is not turning on.Does that mean that the pump is no good?I thought the fuel pump is in the same place as the sending unit.I took it apart and there is no pump there.Am I going to have to drop the tank to get to the fuel pump?Thanks Again,Damon[sm=americanasmiley.gif][sm=groupwave.gif][sm=massbounce.gif][sm=happybounce.gif]

 

That would mean that the fuel pump is the problem. The fuel pump is in a different location than the sending unit.

You are correct, you will have to drop the tank to replace the fuel pump.

 

are you sure? i always thought there was a little hatch underneath the rear passenger seat, or is that only for the wires that lead to the fuel pump?

 

The pax-side hatch only accesses the fuel level sensor. There is no hatch over the fuel pump.

These symptoms (intermittent no-start) were exactly the same on my 94 EX. You can confirm the pump is the problem by "hammering" the pump w/ brief rapid keyswitch applications. This would get mine going when it would not start otherwise. If it starts up, you know the pump is intermittent. Why, it could be a tiny piece of trash or perhaps a weak motor winding that has an internal short reducing the magnetic drive field.

Not too bad a job. You'll need to elevate on jack stands carefully to access the tank. A short flat-top footstool is handy to support the tank as you remove and install. A number of electrical and fuel lines to release. Get a manual of some type! I found releasing the wiring at the electrical connector inside the trunk and feeding wiring harness down through the body hatch was simpler than manual recommendation.

good luck

 

Hello,everybody, I just replaced the fuel pum and it still did not fix the problem. I have changed the,plugs,roter,fule pump and main relay. I am so lost. Does anybody have any sugestions???[sm=americanasmiley.gif][sm=badbadbad.gif]

 

maybe take it to a garage and ask them to diagnose the problem. Then fix it yourself. Certainly much eaiser/cheaper than bringing it to the stealership

 

Same problem? Pump does not come on when keyswitch is turned to ON?

Is the no-start full time or intermittent?

I think it's time to step back and determine whether fuel or spark is missing?

You do realize the fuel pump turns off after 2-3 secs unless you go to Start position? Next time no-start occurs, check the fuel injector rail for fuel pressure by cracking the banjo bolt bleeder or fuel line connection. Use a rag to contain spray. If you get a big spray of fuel, you have fuel pressure, and ignition is your problem.

You can confirm fuel is not the problem by spraying starter fluid or throttle body cleaner into the throttle body entrance while turning engine over. If engine won't kick over momentarily, there is no spark. If you have a timing light check for spark by attaching sensor to one lead and turning engine over. No flashes mean no ignition spark.

Sometimes you can become so sure you know the problem, that you focus on one thing and miss the big picture. I've done this quite a few times and got burnt.

Persistence is necessary. On another forum, a fellow was convinced that he had spark and fuel was the problem. After much futile effort, w/ no success he was frustrated. Earlier, he tested spark w/ a plug grounded to engine and could actually see a spark. However when he finally tested w/ timing light, no flashes. New coil fixed the problem. Not saying coil is your problem, but check as suggested above.

good luck

 

Hello Again, I do thank everybody foryour help. This is so interesting because when the car wont start, The noise from the fuel pump does not sound when I turn the key. For some reason, the fuel pump does not turn on all the time. I have tested the fuel preasure when the pump wont turn on and the preasure does go down. For some reason the pump will not turn on at times. Here is where it gets real good!! When I put the new pump in, it acted perfectly for about a week and it did happen again onetime but, I turned the key again and it worked fine. I have not had a problem since that one time. So,the pump didnt turn on one time in the last month. It has cooled down here in Maine and I am wondering if that might be an issue??? I have replaced the fuel pump,distributer cap,Main Relay,Plugs,wires and cleaned ground to sending unit. My concern is, why does the pump not turn on from time to time and now that it is cool, there has not been a problem. (What else would stop the fuel pump from working every time)?