dman67

Hi Everyone,

I have been searching for a solution to my issue and not found one yet and could use some assistance.

History:

Driving the accord home one night, car dies on highway, coast off to parking lot, try to restart, engine turns over, but won't start. Get car towed home, just for grins turn it over and fires up and runs a minute or 2 and dies. Now it won't start.

Things tried:

Checked for spark with spark tester (Present on all 4 wires, but appeared weak). Replaced Cap, Rotor, Ignitor, Wires, and Coil. Nice strong spark on all wires.

Note: Turning ignition to on position, Check Engine light comes on, then off like it should.

Shot starting fluid in intake, will run until that is depleted.

Replaced Main Relay (No change, still no start, fuel pump not priming)

Dropped Fuel tank, put a Voltmeter on Fuel pump wires, turn key to On, see 12volts across the wires (assume now the Relay is not the issue but it's the fuel pump)

Replaced Fuel Pump (put 12 Volts on the fuel pump prior to install to make sure it worked).....Fuel pump still won't prime after install. I cracked open the inlet to the Fuel rail, to check, no pressure.

Cleaned the ECU GND connection under the Thermostat.

Tested the Main ECU fuse under the hood with an Ohmmeter, shows continuity.

Tested Relay Wire harness between Pins 1+2 and see 12Volts.

Jumped Pin 1 (12V) to Pin 7 (Fuel Pump wire) of the Relay harness, fuel pump will not prime.

I replaced the parts listed above as the car only has 90k miles and looks like nothing was every replaced by the little old lady that owned it before me.

I'm looking for suggestions, could this possibly be an ECU issue?

Do I have an open power wire inside the fuel tank from the Fuel pump connector to the fuel pump?

I will drop the tank and test for connectivity if need be, but what an *** whuppin that was. I want to avoid that and only do it as a last resort.

Any help would be greatly appreciated.

Thanks!

Dman

accordturb96

did you blow a fuse working on the pump by chance?

dman67

I'm not quite sure, I jumpered 12Volts directly to the pump from the Main Relay connector and couldn't get it to turn on. I wouldn't think there is a fuse in series from the output of the wire harness to the fuel pump.

I'll check and see what fuse feeds the pump under the dash/hood just to be sure and report back.

Thanks!

Dman

holmesnmanny

Check all fuses in the engine bay and the driver side kickboard with an ohm meter. There is an ecu fuse in the kickboard fuse assembly

dman67

I checked all fuses under hood and at the box on the drivers side kick panel. All reading good, none burned or reading open.


Thanks.

holmesnmanny

It sounds like the ecu isnt providing ground for the relay.

Use this site to test your fuel system.

http://techauto.awardspace.com

dman67

Last night removed the ECU and hit a bunch of cold solder joints with the iron, made no difference. Next stop, ECU town. I bought a used ECU ebay as a hail mary.

Will post results when installed.

Dman

dman67

Tried another ECU, no dice. Fuel pump still not coming on.

Going to drop the tank this weekend, pull the pump out and connect it back up out of the tank, turn the key on, see if there is any life to it. If not, check voltages again to the fuel pump electrical connector. If voltage is there, going to check it all the way down to wires as they attach to the fuel pump itself.

It sure sounds like there is an open wire or bad connection in the path to the fuel pump. What a pain in the a$$ this has been.


Dman

dman67

I checked the voltage across pins 1+2 of the wiring harness (pin 1 being 12Volts and 2 being ground)

From this diagram below, I see that pin 8 is supposed to be pulled to Ground through the ECU (assuming it is correct). I will check this before I drop the tank, but still not sure how the pin 8 comes into play for the fuel pump. The 2 wires connecting to the fuel pump have to be a ground and +12Volts, when I wired up the new fuel pump, the ground from the fuel pump ties to a screw on the metal outer part of the fuel pump assembly in the tank and the other wire goes to the fuel pump directly (which has to be the 12volt line).

dman67

I see how pin 8 comes into play in the circuit.

Switch in IG1 position, current flows from pin 2 through diode to pin 5 coil. This closes the relay connecting pin 1 completing the circuit to pin 8 (energizing the coil connected to pin 8) and powers the fuel injectors which also closes the relay (pin 7) to provide power to the fuel pump via pin 5 to pin 7.

But I'm throwing in the towel. I'm towing it in and let a local mechanic I trust get to the bottom of it. He is a Honda certified mechanic and has all the diagnostic equipment to root it out.

I'll let everyone know what the problem turns out to be as I have seen a ton of these threads with no solution posted (drives me nuts), so I assume people just drove the car off the cliff and never got it fixed.

Dman

holmesnmanny

Did you apply direct power to the pump and check for pressure ?

Edit: I see you did now. Looks like the pump went out. You say something about dropping the tank. Not sure if that came about.

dman67

Yeah, yesterday I decided to rent a tow dolley and take it in to my mechanic, but that may turn out to be a feat in of itself. I may attempt dropping the tank one more time as a last ditch effort and follow power and ground paths all the way down to the pump inside the assembly. It seems like there is an open path somewhere.

When I replaced the pump (not the whole assembly) I tested power to the connector (had 12Volts for 2 seconds) and I put 12Volts across the pump before I installed it in the assembly to make sure the pump worked, but like a dummy I didn't hook it up prior to installing in the tank, I assumed power on the connector and the pump working it was going to be smooth sailing. The only thing I can think is that the path from the actual connector on top of the assembly down to the fuel pump itself has an open Ground or 12Volt path.

I'll report back when I psych myself up to drop the tank one more time.

Thanks!

Dman67

NerfGunner420

get a ground from the body or the battery! and vice versa to check for voltage

dman67

In process of dropping the tank and following continuity with my meter all the way down in the tank to pump. It has been too cold to get underneath the car. Managed to drain the tank but that was it.

Will post results soon.

Dman

dman67

Update:

Dropped the tank, pulled out the pump.

I tested for continuity of ground and power from the Fuel pump connector on the top of assembly into the connection directly on the pump....Good.

Tested Ground from Battery all the way to the Ground on the fuel pump connector.....Good.

Tested continuity from pin 7 on the relay harness all the way to the connector on the fuel pump....Good.

Plugged fuel pump into the connector out of the tank and turned key on....Pump comes on.

I'm at a loss as to what the he!! the problem is.

Either the fuel pump is not building pressure or the fuel line is clogged.

I noticed the Fuel pump strainer on the new pump was kinda bent up after I took it out so I'm going to bite the bullet and get a complete assembly and drop it in.

I'll also disconnect the fuel line to the fuel filter and try and blow through it and see if it is clogged.

If anyone has any other suggestions, I'm all ears.

holmesnmanny

(Edit : See next post)

holmesnmanny

If the pump works then you dont have a fuel pressure issue.

How did you previously determine you had a fuel pressure issue ?

dman67

As stated in my previous post, I connected the real connector to it, fed from the Relay and turned the key on and the pump came on for the 2 seconds (did this twice just for good measure)

Shouldn't that confirm the same as applying direct power to it?

On a side note, I assume that if the fuel pump "primes" but doesn't come on when in the start (motor turning over condition) there would still be enough fuel pressure to at least run for a few seconds, but it will not even attempt to start. Also, in a previous test, when I crack the fuel line to the fuel rail there is no gas coming out.

I also noticed when I just tested the fuel pump out of the tank, when the fuel pump is on, it is very quiet, which may explain why I had trouble hearing it when installed in the tank.

Thanks for the suggestions.

dman

holmesnmanny

The fuel pump will only prime for two seconds and then be turned off if the car fails to start. It does this as a fail safe just in case of an accident. The ecu is in charge of this.

If the fuel pump is working properly then something else is the cause of your non start.

Once you verified initially before pulling the pump that it was turning on you should be looking to other reasons your car is not starting instead of pulling the pump when it is working fine.

dman67

I understand about the 2 second on/off for the fuel pump, but I could NOT hear the fuel pump prime when the key was turned to the ON position, so I assumed it was not priming, the only way to confirm for sure was to pull the thing out again and see if it was coming on. But even if it is coming on, does not mean that it is providing enough pressure, and as far as I can tell, there is no pressure seen at the fuel rail when I cracked it open and turn the key to the ON position.

When I replaced just the pump recently, I also replaced the fuel filter at the same time.

Either the fuel pump is weak or there is some blockage.

I'm going to go to the local Autozone and get a new pump assembly and a fuel pressure gauge as well.

Thanks for the suggestions.

Dman

holmesnmanny

Do it the right way. Get a fuel pressure kit from Harbor Freight for $20. Hook it up. Check pressure. Take the kit back and get your money back, minus the $5 restocking fee. Since the pump is out you may as well get a new Denso now.

Good luck finding a fuel pressure kit elsewhere that fits our fuel rail.

dman67

It's alive and kicking now.

I replaced the whole fuel pump assembly, tested it, installed it, tested the new fuel pump after installing it, making sure the pump was pumping from the high pressure connection, then connected the high pressure connection by the rear tire and then verifying pressure at the fuel rail.

Started up the first try. So far so good.

Thanks for all the help and suggestions.

Dman