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Old 11-22-2019   #1
Flyman 27
 
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Default Another No-Start Condition

This happened a couple weeks ago & I have been chasing it since.
One day the car just failed to start (cold). It turns over fine, just no fuel.
I jumpered the pumps & they run fine, and build pressure fine.

The pump relays are not getting power, neither are the fuses.

I did do a 10 minute "alarm bypass" procedure & it started right up and showed full fuel pressure. But as soon as I shut it off, it is back to having no power to the pumps again.

Been working on the interior & got to the point where I could drop the steering column.
So I tried the Vats bypass.
The key pucks read 683 (#3)
The closest resister was 674, I assume that is close enough.

I soldered the resister into the end of the conn on the strg column.
Tried to start it, and the engine will still not fire.
It turns over fine, it is just getting no fuel.

I pulled back out the resister to verify everything
.
The Chart reads "design" resistance = 681 Min = 650 Max = 728 My keys read 683 The resister reads 674, right down the middle.The keys are the ones I've been using ever since my column was rebuilt, maybe 2 years ago.

Where is the alarm function located?
Can it be replaced or by-passed?
Possible options??
Any ideas?
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Last edited by Flyman 27; 11-22-2019 at 05:18 PM.
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Old 11-25-2019   #2
onetinsoldier
 
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Default Re: Another No-Start Condition

Have you put a fuel pressure gauge on it to see if the rails have fuel ?
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Old 11-25-2019   #3
Flyman 27
 
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Default Re: Another No-Start Condition

Also:
Went to see Mark Haibeck this morning, he was going to turn off the Vats system in my MEMCAL to eliminate that possability. But the Vats was already turned off in my MEMCAL.

The fuel condition is as follows:

Jumper from Battery to the pumps, pumps run & I have full pressure.
Jumper from Battery to underhood test lead, pumps run & I have full pressure.
Turn the key on (should prime) and pumps don't run & I have "0" pressure.
Turn the key to start & pumps don't run & I have no pressure.

I have also replaced both pump relays, just to be sure. NOS GM relays.
Checked all fuses, in box & under dash panel. All are good, replaced them anyway.

So my list of possibilities is getting short.

I was warned that it could be my ECM (hope not!).
I am at a loss as to what to test next.

I did do a 10 minute "alarm bypass" procedure & it started right up and showed full fuel pressure. But as soon as I shut it off, it is back to having no power to the pumps again.

That doesn't make sense to me.
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Old 11-27-2019   #4
Flyman 27
 
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Default Re: Another No-Start Condition

Found it almost by accident.
The problem was intermittent and very confusing.
It ended up being the wire conn for the fuel pump sending unit.
It would test fine, then kick out.
I had the key on & was checking stuff & I could hear the pump kicking in and out.
So it is a simple fix, I ordered new weather-proof conns from Amazon & I will be good to go!
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Old 11-27-2019   #5
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Default Re: Another No-Start Condition

Its usually the simple stuff first. We all have a tendency to escalate things.
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Old 11-27-2019   #6
Flyman 27
 
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Default Re: Another No-Start Condition

The problem was intermittent, it would test fine, so I would ignore that area, then proceed. Then I would get other faults that didn't make sense, so I tested everything over. And again, it all tested fine. Then it would fault when I tried to start it.
It was not an easy problem to find because the "fault" kept moving.

I kept testing the circuits, but not the amp draw of the pumps. That is where I failed.
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Old 11-27-2019   #7
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Default Re: Another No-Start Condition

Quote:
Originally Posted by XfireZ51 View Post
Its usually the simple stuff first. We all have a tendency to escalate things.
Ain't that the truth! I can scream APOCALYPSE faster than anyone!
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Old 12-01-2019   #8
JThomas
 
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Default Re: Another No-Start Condition

Quote:
Originally Posted by Flyman 27 View Post
Found it almost by accident.
The problem was intermittent and very confusing.
It ended up being the wire conn for the fuel pump sending unit.
It would test fine, then kick out.
I had the key on & was checking stuff & I could hear the pump kicking in and out.
So it is a simple fix, I ordered new weather-proof conns from Amazon & I will be good to go!
Thanks for posting. I'm not as knowledgeable as most of the guys on this forum, but I learn a little bit each time I read something someone else has gone through. Glad you found the fix.
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Old 02-08-2020   #9
Corvette95
 
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Default Re: Another No-Start Condition

Quote:
Originally Posted by Flyman 27 View Post
Found it almost by accident.
The problem was intermittent and very confusing.
It ended up being the wire conn for the fuel pump sending unit.
It would test fine, then kick out.
I had the key on & was checking stuff & I could hear the pump kicking in and out.
So it is a simple fix, I ordered new weather-proof conns from Amazon & I will be good to go!
Where was this connector...was it under the dash or do you mean the actual connector on the unit in the tank?
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Old 02-08-2020   #10
Flyman 27
 
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Default Re: Another No-Start Condition

Quote:
Originally Posted by Corvette95 View Post
Where was this connector...was it under the dash or do you mean the actual connector on the unit in the tank?
It was the conn at the sender unit. It looked fine, but there were corrosion issues inside the connector.
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