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89 has spark and fuel..won't start

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Old Apr 29, 2021 | 05:39 AM
  #31  
Brad G's Avatar
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In the same boat. Tested my plugs finally last night. Had to buy a fuel pressure gauge and plan on testing tonight as well.

With this forum and cruiser's help, maniax99, we'll get this!
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Old Apr 29, 2021 | 12:17 PM
  #32  
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Ok I was able to test the fuel pressure finally.

Only twice did I ever get over zero. I got 30 twice.


I never got it to start, though. I got no readings at all until I messed with that little solenoid that manix also did.


After I disconnected and reconnected the solid green one middle left, it jumped to 30 PSI. but I never got it to start. Perhaps it was a coincidence since I was starting it and trying to watch through the crack in the hood for changes to the gauge.

I can try again tomorrow with a second person.

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Old Apr 29, 2021 | 06:31 PM
  #33  
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30 is 10 pounds too low.
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Old Apr 29, 2021 | 06:49 PM
  #34  
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Originally Posted by cruiser54
30 is 10 pounds too low.
I just got it started, and it's running at 30 PSI constantly. I hear the pump priming now, too. And a few posts up I mentioned (I think) that on my Renix Monitor II that my oxygen relay voltage had recently dropped real low around when this started.

Well, I was cleaning out the relay plugs on the passenger side for the umpteenth time - the ones I assume are a fuel pump reply, the o2 heater relay, and 2 others - so on a hunch...I just swapped two of them. I turned the key, heard the pump, it started right up, my o2 heater reading was back in the 13s (it was dropping under 1 for a while here).

I wanted to check voltages on the fuel pump but I am not sure where to check for it. Do I take that back panel off again behind the spare tire?

I am going to give it a bit and go see if it starts again.

Weird?
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Old Apr 29, 2021 | 06:55 PM
  #35  
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Might do some more pokin around that relay center.
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Old Apr 29, 2021 | 07:10 PM
  #36  
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It was the middle two I swapped, although I don't have a power latch (well, I don't think). All of them have been removed and cleaned at some point, used a dental pick to clean and pry the contacts a little on all of them, too. But this definitely is starting to make sense.

All the relays looked the same ? I will try to get the block out this weekend and check the wiring underneath it.
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Old Apr 29, 2021 | 07:41 PM
  #37  
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Relays all the same.
What can happen is the wires coming up into the block can back out.
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Old May 1, 2021 | 04:49 PM
  #38  
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so i tested the fuel pressure...i got about 31-32 psi with the key off. it stayed around 30psi for like 5 minutes before i release the pressure. i then turned the key to ON and got 0. i tried cranking and got 0.

i think the fuel pressure tester might have failed at some point because it wont give me a reading. i tried getting a reading with the key off and got 0. ive tried on a working car and still nothing. So i need to go get another tester. Any other thing i should try aside from the fuel pressure?

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Old May 1, 2021 | 05:04 PM
  #39  
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Originally Posted by Brad G
In the same boat. Tested my plugs finally last night. Had to buy a fuel pressure gauge and plan on testing tonight as well.

With this forum and cruiser's help, maniax99, we'll get this!
thanks! hopefully we can figure it out lol
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Old May 1, 2021 | 06:29 PM
  #40  
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Originally Posted by maniax99
so i tested the fuel pressure...i got about 31-32 psi with the key off. it stayed around 30psi for like 5 minutes before i release the pressure. i then turned the key to ON and got 0. i tried cranking and got 0.

i think the fuel pressure tester might have failed at some point because it wont give me a reading. i tried getting a reading with the key off and got 0. ive tried on a working car and still nothing. So i need to go get another tester. Any other thing i should try aside from the fuel pressure?
My tester would read 0 many times too, while cranking. Then occasionally it would hit 30 and still wouldn't start, then occasionally hit 30 and would start.

I cleaned all four of the relays and their sockets and tightened up all the pins today. Mine has started every time the last several days. Tomorrow I drive it around further than the neighborhood.
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Old May 1, 2021 | 07:51 PM
  #41  
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A bit of a reminder to all in this thread.

My Tips are a MUST right off the bat. Save yourselves some headaches and JUST DO EM!
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Old May 1, 2021 | 07:54 PM
  #42  
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Originally Posted by cruiser54
A bit of a reminder to all in this thread.

My Tips are a MUST right off the bat. Save yourselves some headaches and JUST DO EM!
Hallelujah on this fine morning!
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Old May 1, 2021 | 08:12 PM
  #43  
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Hey Roler!!
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Old May 3, 2021 | 01:38 PM
  #44  
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Originally Posted by cruiser54
Fuel pressure needs to be measured.
so i tested the fuel pressure...i got about 31-32 psi with the key off. it stayed around 30psi for like 5 minutes before i release the pressure. i then turned the key to ON and got 0. i tried cranking and got 0.

i think the fuel pressure tester might have failed at some point because it wont give me a reading. i tried getting a reading with the key off and got 0. ive tried on a working car and still nothing. So i need to go get another tester. Any other thing i should try aside from the fuel pressure?
Reply
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