 Resident 1.8 L-jet experts, a little help please... |
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| Blue6 |
 Nov 4 2015, 06:45 PM
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Senior Member  Group: Members Posts: 1,057 Joined: 3-October 13 From: SoCal Member No.: 16,470 Region Association: Southern California 
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My 1974 1.8 completely stock has a problem. Every couple of days it will only stay running about three seconds. No mater how many times I try to start it, it just runs for three seconds then dies. Other days it will run great.
I checked the power to the fuel pump, and get 10.86 while cranking. When I plug the fuel pump back in and crank the engine, it doesn't do anything. No noise, no vibration. I removed the pump and jumped it with a battery, and it spins like it should. What am I missing. Thank you... |
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| timothy_nd28 |
Nov 10 2015, 01:09 PM
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Advanced Member Group: Members Posts: 2,299 Joined: 25-September 07 From: IN Member No.: 8,154 Region Association: Upper MidWest
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This seems odd. The fuel pump is turned on by two methods. When you turn the ignition key to crank, the dual relay supplies power to the fuel pump momentarily (we tested this earlier and is proven to work). The fuel pump is only on when the key is turned and engine cranking. Once you release the key (hopefully engine now running), the air flow meter engages the dual relay to keep the fuel pump active.
What you are describing is that the car will start and stay running with the airflow meter connector off. What's keeping the fuel pump on? You may need to post some pictures of your engine bay, perhaps the fuel pump wiring is not original and has been bypassed. We need to solve this problem first before any other diagnostics. Do you own a fuel pressure test gauge? We will need this too. |
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Posts in this topic
Blue6 Resident 1.8 L-jet experts, a little help please... Nov 4 2015, 06:45 PM
timothy_nd28 Sounds like a failing dual relay Nov 4 2015, 09:44 PM timothy_nd28 Grab a voltmeter and set it for DC. Put the positi... Nov 4 2015, 10:10 PM Bleyseng Maybe a loose wire in the dual relay connector. Th... Nov 5 2015, 09:10 AM Blue6 Thank you Timothy and Geoff for the info. I should... Nov 5 2015, 10:55 AM Blue6 Geoff, checked that dual relay. Everything looked ... Nov 9 2015, 08:45 PM timothy_nd28 Interesting, how long will it idle with the AFM co... Nov 9 2015, 08:59 PM Blue6 When I start it using starting fluid, it will run ... Nov 9 2015, 09:52 PM CooltimesJr not sure if this will help you or not, but the per... Nov 10 2015, 12:03 AM CooltimesJr or maybe Dave will chime in since he is an admin t... Nov 10 2015, 12:05 AM Blue6 Thank you Cooltimes, everything helps. With the he... Nov 10 2015, 10:43 AM Dave_Darling Sounds like you have good avenues of inquiry here.... Nov 10 2015, 07:35 PM
Blue6 Been chasing wires, and so far everything looks st... Nov 10 2015, 07:55 PM |
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