fuel delivery - Intermittent - Page 2

Trevor · #16 05-03-2010, 10:56 PM

The constant voltage on the blue wire with the fuel pump relay removed, in no way adds up. Are you absolutely shore that you have located and are dealing with the correct relay?

As you will see from the diagrams, provided that you have the correct relay removed, there surely must be a short between blue and yellow, which appears unlikely.

Jonnycash · #17 05-04-2010, 08:32 PM

Quote:

Originally Posted by Trevor

The constant voltage on the blue wire with the fuel pump relay removed, in no way adds up. Are you absolutely shore that you have located and are dealing with the correct relay?

As you will see from the diagrams, provided that you have the correct relay removed, there surely must be a short between blue and yellow, which appears unlikely.

I am positive I have located the correct relay.
The problem seems to be intermittent, as the car died today. I immediately checked the voltages, the blue wire was 0v.
I plugged the relay in, and it started right up, and also had correct voltage.
I then unplugged the relay while idling in my driveway, and it kept running.
I again checked the voltage it was again constant 12v.
I am thinking the problem lies between the positive battery cable and the fuse box, but I haven't been able to locate it yet.
My work schedule is crazy right now, so daylight is limited for me.

Trevor · #18 05-04-2010, 11:07 PM

Quote:

Originally Posted by Jonnycash

I am positive I have located the correct relay.
The problem seems to be intermittent, as the car died today. I immediately checked the voltages, the blue wire was 0v.
I plugged the relay in, and it started right up, and also had correct voltage.
I then unplugged the relay while idling in my driveway, and it kept running.
I again checked the voltage it was again constant 12v.
I am thinking the problem lies between the positive battery cable and the fuse box, but I haven't been able to locate it yet.
My work schedule is crazy right now, so daylight is limited for me.

You are involved with an intermittent stinker.

If there is no short anywhere along the lines I have suggested, you will have to start suspecting the ECU.

Sincerely, the very best of luck with it.

sowise · #19 05-05-2010, 05:17 AM

I know Trevor has been helping you with this and I haven't bothered to pull the wiring drawings but wondering if you verified your ignition is off even with the key removed.

Trevor · #20 05-05-2010, 05:26 AM

Quote:

Originally Posted by sowise

I know Trevor has been helping you with this and I haven't bothered to pull the wiring drawings but wondering if you verified your ignition is off even with the key removed.

He appears quite knowledgeable, so that I am sure that he would have noticed if his dash lights were illuminated.

Jonnycash · #21 05-05-2010, 05:45 AM

Quote:

Originally Posted by Trevor

You are involved with an intermittent stinker.

If there is no short anywhere along the lines I have suggested, you will have to start suspecting the ECU.

Sincerely, the very best of luck with it.

hmmm...
My next test will be to disconnect the ecu and check voltages.
If the problem still exists, I believe that would rule it out.

Trevor · #22 05-05-2010, 02:29 PM

Quote:

Originally Posted by Jonnycash

hmmm...
My next test will be to disconnect the ecu and check voltages.
If the problem still exists, I believe that would rule it out.

Good one, you are tracking like a blood hound.

NikFu S. · #23 01-09-2011, 03:20 PM

How did this go?

Jonnycash · #24 01-09-2011, 05:02 PM

Quote:

Originally Posted by NikFu S.

How did this go?

Turned out to be a bare spot on the positive fuel pump wire after the relay.

Austin · #25 10-16-2011, 09:33 AM

Quote:

Originally Posted by Trevor

...Are you absolutely shore that you have located and are dealing with the correct relay?

For anyone interested, I'm picking up one today from Advance Auto Parts:

BWD Relay Part # R3054Z

I'm sure it can be found at any parts store, but I wanted to post this so people could see a picture of the actual part. Also, apparently it's a REALLY common relay as it's used in a ton of common makes (Toyota, Honda, Mitsubishi, etc.)

(not to be annoying, rather to be helpful, I'm going to cross post this in some other fuel pump relay threads just in case anyone is searching...)

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FWIW, turns out it was a loose ground wire on the FP module in the trunk.