Main Relay - No second click for priming fuel pump
#1
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Main Relay - No second click for priming fuel pump
Ok.. I've tested the relay and it is good. I opened it up and didn't see any cracks or burned components and no burning smell.
I tested the harness according to the Helms manual, and all checks ok.
The only thing I wasn't able to check was the ECU signals at the ECU harness because I don't have a test harness.
I've noticed that the fuel pump will prime if the ambient temperature is less than 80 degrees. This afternoon, it was 87 degrees (according to the news radio) and my fuel pump wouldn't prime no matter how much I tried. (There was no second click in the relay).
I came back to the car when the temperature dropped to the high 70's and it started right away..
Here is what happens. I turn the key to on (second position). The CEL stays on and the S3 light on the dash blinks. Sometimes with CEL will go away and sometimes the s3 light doesn't blink, but still the main relay only clicks once.
How can I check the ECU signal that turns on the fuel pump circuit in the relay ? I don't have a test harness (anyone want to sell me one?)
This problem only happens in hot weather. Should I open up my ECU and check it? Would the fuel pump fail to prime if the Transmission computer went bad ?
I tested the harness according to the Helms manual, and all checks ok.
The only thing I wasn't able to check was the ECU signals at the ECU harness because I don't have a test harness.
I've noticed that the fuel pump will prime if the ambient temperature is less than 80 degrees. This afternoon, it was 87 degrees (according to the news radio) and my fuel pump wouldn't prime no matter how much I tried. (There was no second click in the relay).
I came back to the car when the temperature dropped to the high 70's and it started right away..
Here is what happens. I turn the key to on (second position). The CEL stays on and the S3 light on the dash blinks. Sometimes with CEL will go away and sometimes the s3 light doesn't blink, but still the main relay only clicks once.
How can I check the ECU signal that turns on the fuel pump circuit in the relay ? I don't have a test harness (anyone want to sell me one?)
This problem only happens in hot weather. Should I open up my ECU and check it? Would the fuel pump fail to prime if the Transmission computer went bad ?
#2
Re: Main Relay - No second click for priming fuel pump (arren123)
I think I may be having the same problem, can you tell me where the main/fuel relay is and how to check it please? I've got a 92 Acura integra and it sounds as if the fuel pump isn't even energizing.
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Re: Main Relay - No second click for priming fuel pump (Guari)
Here are the Helms instructions
http://www.typer.us/images/PGMFI-1.jpg
http://www.typer.us/images/PGMFI-2.jpg
http://www.typer.us/images/PGMFI-3.jpg
Let me know what you find.
http://www.typer.us/images/PGMFI-1.jpg
http://www.typer.us/images/PGMFI-2.jpg
http://www.typer.us/images/PGMFI-3.jpg
Let me know what you find.
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Re: Main Relay - No second click for priming fuel pump (arren123)
Update.. Now I'm not sure what it is.
It was hot again in the beginning of the week high 80's low 90's .
I tried to start the car and it had the same symptoms. No second click.
So I reached under the dash with my left hand and tried to push the relay wires at the harness to the side while I turned the key to on..
Eventually, I got it to click.
I tried again the next day when the temparature was 97 degrees and the relay clicked 2 times like it should. The car also started up right away.
Maybe I have bad wiring ? But what I don't understand is this.. If the wiring is bad, why doesn't the relay shut off while I'm driving ?
It was hot again in the beginning of the week high 80's low 90's .
I tried to start the car and it had the same symptoms. No second click.
So I reached under the dash with my left hand and tried to push the relay wires at the harness to the side while I turned the key to on..
Eventually, I got it to click.
I tried again the next day when the temparature was 97 degrees and the relay clicked 2 times like it should. The car also started up right away.
Maybe I have bad wiring ? But what I don't understand is this.. If the wiring is bad, why doesn't the relay shut off while I'm driving ?
#7
Re: Main Relay - No second click for priming fuel pump (arren123)
Update.. Now I'm not sure what it is.
It was hot again in the beginning of the week high 80's low 90's .
I tried to start the car and it had the same symptoms. No second click.
So I reached under the dash with my left hand and tried to push the relay wires at the harness to the side while I turned the key to on..
Eventually, I got it to click.
I tried again the next day when the temparature was 97 degrees and the relay clicked 2 times like it should. The car also started up right away.
Maybe I have bad wiring ? But what I don't understand is this.. If the wiring is bad, why doesn't the relay shut off while I'm driving ?
It was hot again in the beginning of the week high 80's low 90's .
I tried to start the car and it had the same symptoms. No second click.
So I reached under the dash with my left hand and tried to push the relay wires at the harness to the side while I turned the key to on..
Eventually, I got it to click.
I tried again the next day when the temparature was 97 degrees and the relay clicked 2 times like it should. The car also started up right away.
Maybe I have bad wiring ? But what I don't understand is this.. If the wiring is bad, why doesn't the relay shut off while I'm driving ?
HELP! Did you ever find the issue? Currently sitting in the heat after new relay and still heard no click or prime. Touched the relay and moved before trying again and it worked! Left it for an hour and came back it starts up fine. All I can say is on hot days after driving and letting it sit relay will possibly not work.
if you solved this let me know! Thanks!
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