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second wind |
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#1
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Senior Member ![]() ![]() ![]() Group: Members Posts: 862 Joined: 30-December 10 From: Los Angeles, California Member No.: 12,543 Region Association: Southern California ![]() ![]() |
Hello teener world....my fuel pump was having intermittent on/off issues and after messing up a few wires and swapping a few relays it seems to be consistently working now...new Optima battery didn't hurt things...still doesn't run and after a good three hour attack yesterday with seasoned 914'er figured out there is no gas coming out of the injectors.....plenty of pressure in the fuel rails but no spray out of the injectors. Got a pop or two after jiggling a few ground wires but all the ground wires seem to be nailed down down. The consensus is that it is either the wiring harness is messed up or the ECU may be bad. The wires have cracks in the plastic covering of course and everyone says that the ECU going bad is very rare....but possible. I would really appreciate your opinion on the subject and my car is a 1973 2.0 in case someone has a spare ECU on hand. Thank you very much and I need to get back on the road bad....I am only as happy as my car is running...I'm funny that way.
All the best, Greg |
Geezer914 |
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#2
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Geezer914 ![]() ![]() ![]() Group: Members Posts: 1,907 Joined: 18-March 09 From: Salem, NJ Member No.: 10,179 Region Association: North East States ![]() ![]() |
If you are jiggling wires and getting a hit now and then, I would check the wire harness. Strip back the cracked dried up wire and replace it with new wire of the same guage. You are correct, the ECU's rarely go bad.
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mgphoto |
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#3
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"If there is a mistake it will find me" ![]() ![]() ![]() Group: Members Posts: 1,375 Joined: 1-April 09 From: Los Angeles, CA Member No.: 10,225 Region Association: Southern California ![]() |
Rarely is not never, fuel pump never shuts off, big clue.
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rjames |
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#4
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I'm made of metal ![]() ![]() ![]() ![]() Group: Members Posts: 4,231 Joined: 24-July 05 From: Shoreline, WA Member No.: 4,467 Region Association: Pacific Northwest ![]() ![]() |
nothing in your description points to the ECU yet.
If you suspect bad wiring get a multimeter and check for continuity. |
mgphoto |
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#5
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"If there is a mistake it will find me" ![]() ![]() ![]() Group: Members Posts: 1,375 Joined: 1-April 09 From: Los Angeles, CA Member No.: 10,225 Region Association: Southern California ![]() |
Here is another little clue, a noid light hooked up to cylinder #3 lights briefly when the key is turned on and does not flash as the engine is cranked.
That along with the fuel pump not stopping after 2 seconds with the key on. Check resistance on the cylinder head sensor. |
second wind |
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#6
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Senior Member ![]() ![]() ![]() Group: Members Posts: 862 Joined: 30-December 10 From: Los Angeles, California Member No.: 12,543 Region Association: Southern California ![]() ![]() |
I did forget to mention prior to my current issue that when starting first thing in the morning the fuel pump will run for way more than two seconds....in fact I begin to start the car while the fuel pump is still going and the car will start just fine....then once warm when I turn the key to start the fuel pump with shut off in 2-3 seconds like it is supposed to and then I turn key to start and it starts just fine. I will keep thinking of additional clues. The wiring harness may have cracked insulation but the wire inside is still in there and functioning....correct? And a short will burn up something or blow a fuse....correct? The old harness can still function...right? I am all ears on any other thoughts....thank you again.
Greg |
mgphoto |
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#7
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"If there is a mistake it will find me" ![]() ![]() ![]() Group: Members Posts: 1,375 Joined: 1-April 09 From: Los Angeles, CA Member No.: 10,225 Region Association: Southern California ![]() |
I did forget to mention prior to my current issue that when starting first thing in the morning the fuel pump will run for way more than two seconds....in fact I begin to start the car while the fuel pump is still going and the car will start just fine....then once warm when I turn the key to start the fuel pump with shut off in 2-3 seconds like it is supposed to and then I turn key to start and it starts just fine. I will keep thinking of additional clues. The wiring harness may have cracked insulation but the wire inside is still in there and functioning....correct? And a short will burn up something or blow a fuse....correct? The old harness can still function...right? I am all ears on any other thoughts....thank you again. Greg No fuses in the fi system. Low voltage electronics. A short will just change function, no burning wires unless shorted with high voltage. |
Lockwodo |
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#8
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Member ![]() ![]() Group: Members Posts: 213 Joined: 23-December 21 From: Santa Cruz, Californnia Member No.: 26,193 Region Association: Northern California ![]() ![]() |
Make sure the trigger points are functional and plugged in to the wiring harness. If not, the fuel injection system won't work.
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JeffBowlsby |
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#9
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914 Wiring Harnesses & Beekeeper ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 8,895 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None ![]() ![]() |
I did forget to mention prior to my current issue that when starting first thing in the morning the fuel pump will run for way more than two seconds....in fact I begin to start the car while the fuel pump is still going and the car will start just fine....then once warm when I turn the key to start the fuel pump with shut off in 2-3 seconds like it is supposed to and then I turn key to start and it starts just fine. I will keep thinking of additional clues. The wiring harness may have cracked insulation but the wire inside is still in there and functioning....correct? And a short will burn up something or blow a fuse....correct? The old harness can still function...right? I am all ears on any other thoughts....thank you again. Greg You are making a number of significant assumptions, any one of which could be critical and cause the symptoms and faulty behaviors you are noting. It is clear that your harness is toast. In addition you may be having issues with other FI components. Each ones function can and should be fully verified. |
jim_hoyland |
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#10
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Get that VIN ? ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 9,679 Joined: 1-May 03 From: Sunset Beach, CA Member No.: 643 Region Association: Southern California ![]() ![]() |
New harness; when I replaced mine, we found a broken wire inside the casing. And, a replacemt is going to give you a ton of confidence; that is, until a new problem arises… (IMG:style_emoticons/default/biggrin.gif)
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second wind |
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#11
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Senior Member ![]() ![]() ![]() Group: Members Posts: 862 Joined: 30-December 10 From: Los Angeles, California Member No.: 12,543 Region Association: Southern California ![]() ![]() |
Thank you all...will continue tomorrow....how much $$$ is a new harness BTW?
Thank you very much!! Greg |
emerygt350 |
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#12
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Advanced Member ![]() ![]() ![]() ![]() Group: Members Posts: 2,832 Joined: 20-July 21 From: Upstate, NY Member No.: 25,740 Region Association: North East States ![]() |
How do you feel about your trigger points? That would be where i would start. Ignore the other stuff untill you know they are functioning.
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Lockwodo |
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#13
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Member ![]() ![]() Group: Members Posts: 213 Joined: 23-December 21 From: Santa Cruz, Californnia Member No.: 26,193 Region Association: Northern California ![]() ![]() |
How do you feel about your trigger points? That would be where i would start. Ignore the other stuff untill you know they are functioning. (IMG:style_emoticons/default/agree.gif) |
JeffBowlsby |
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#14
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914 Wiring Harnesses & Beekeeper ![]() ![]() ![]() ![]() ![]() Group: Members Posts: 8,895 Joined: 7-January 03 From: San Ramon CA Member No.: 104 Region Association: None ![]() ![]() |
Thank you all...will continue tomorrow....how much $$$ is a new harness BTW? Thank you very much!! Greg All avaibaility and pricing is on m harness website...scroll about 1/2 way down. https://bowlsby.net/914/WiringHarnesses/ If you will PM me your zip code and email address I am happy to send you a full quote with shipping cost and payment details. |
Tjmrfe |
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#15
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NON IMPEDING RATIONE COGITATIONIS ![]() ![]() Group: Members Posts: 132 Joined: 10-April 15 From: Cornwall on Hudson, New York Member No.: 18,612 Region Association: North East States ![]() |
Hello teener world....my fuel pump was having intermittent on/off issues and after messing up a few wires and swapping a few relays it seems to be consistently working now...new Optima battery didn't hurt things...still doesn't run and after a good three hour attack yesterday with seasoned 914'er figured out there is no gas coming out of the injectors.....plenty of pressure in the fuel rails but no spray out of the injectors. Got a pop or two after jiggling a few ground wires but all the ground wires seem to be nailed down down. The consensus is that it is either the wiring harness is messed up or the ECU may be bad. The wires have cracks in the plastic covering of course and everyone says that the ECU going bad is very rare....but possible. I would really appreciate your opinion on the subject and my car is a 1973 2.0 in case someone has a spare ECU on hand. Thank you very much and I need to get back on the road bad....I am only as happy as my car is running...I'm funny that way. All the best, Greg Greg, Just recently I had my tank out, cause I was bored…and lo and behold, it was rubbing a fuel pump wire against the body! While nothing had come from it yet, I thought, damn…I dodged a bullet there. Just a thought, possibly I’m not the only one to have such an issue? Good luck. |
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