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van died and no start recent spider change

2K views 14 replies 6 participants last post by  mattinak 
#1 ·
after an initial problem with install of spider (fuel supply line was leaking) van was running decent for a couple days.

Yesterday heading home and van just died. Towed it home and did some testing.

Pump activates at start and engine turns over well but does not fire at all.

Pump primes for 2 seconds with key flick and runs while trying to start but will not run when test lead at relay is connected to 12v

engine will start with lighter fluid

ecm fuses are good

fuel pressure at schrader valve reads a little over 30 when priming and while cranking and then falls to zero.

fuel pump is only a few years old but what I dont understand is if its the fuel pump why is the pressure not holding at the schrader valve? It immediately falls to zero when I turn the key off
 
#3 ·
Because the fuel pump can't maintain the little pressure it did produce. Your pump has failed and the little piece of hose that connects it to the hanger assembly has also failed.

Replace the pump with AC Delco only. There's a guy on ebay that sells the AC Delco fuel pump rebuild kit with instructions if your fuel level sender (gas gauge) is correct for under $60.
 
#4 ·
Not sure what the specs are suppose to be but as I am trying to diagnose similar problem ( I am believing my #5 is leaking) anyways as for pressure mine hit 50.at prime up and 60-62 while running ..30 seems low or mine seems high? Also found a fucking rat nest by the distributor when I took dog house off..how hard was it to remove the plenum that covers the fuel spider did you have to remove the a/c compressor completely?
 
#5 ·
Leeann_93 said:
Because the fuel pump can't maintain the little pressure it did produce. Your pump has failed and the little piece of hose that connects it to the hanger assembly has also failed.

Replace the pump with AC Delco only. There's a guy on ebay that sells the AC Delco fuel pump rebuild kit with instructions if your fuel level sender (gas gauge) is correct for under $60.
Roger that Leeann, I actually have the original pump that got switched out for the non oe one in there now because I jumped to conclusions at a no start situation and it was the fuse link connector behind the battery so I think I can get back in business till a new oe one can arrive.

thank you for your help.
 
#6 ·
astroman97 said:
Not sure what the specs are suppose to be but as I am trying to diagnose similar problem ( I am believing my #5 is leaking) anyways as for pressure mine hit 50.at prime up and 60-62 while running ..30 seems low or mine seems high? Also found a **** rat nest by the distributor when I took dog house off..how hard was it to remove the plenum that covers the fuel spider did you have to remove the a/c compressor completely?
Pretty sure your pressure is good, and mine is definitely to low. Plenum pull is pretty easy, but I have no air conditioning it was removed when it died awhile back. Pretty easy to get along without up here. I pulled the distributor cap to make it easier to move the plenum back.
 
#12 ·
well I pulled the plenum again and checked the new spider and supply lines for any obvious issues, found none.

I didnt take the regulator off as its brand new and was running for a few days before the abrupt halt obviously caused by no fuel getting into the cylinders.

new fuel pump, new filter and still only getting 30 psi at the schrader valve.

All I can think of at this point is there is a blockage in the gas line somewhere between the pump and the schrader valve.

What I cant understand is where is the pressure escaping to (both old and new fuel pump work and but only generate 30 psi and it immediately drops to 0 when pump turns off).

Why would a system that is designed to hold 60 psi for hours if not days, lose 30 psi instantly?

I'm not seeing or smelling a fuel leak anywhere so if there is a leak it must be going back into the tank so could it have something to do with the fuel line that returns to the tank from the spider? Is that controlled by the spider, or is there another way for the pressure the fuel pump puts into the supply line to bleed out into either the tank or the return line thus keeping the pump from ever achieving 60psi and causing it to instantly lose the 30psi it can generate ?
 
#14 ·
CoolCat4Christ said:
Most of you have probably ran across this article. If not here you go....
http://www.tomorrowstechnician.com/living-under-the-hood-diagnosing-central-port-fuel-injection/
Ok I had read that article a few times before posting but read it a few more and realized for the first time there might be a leak in a spider/regulator without any gas showing up along the lines or under plenum.

So I took the new spider off completely, blocked the supply fuel line off where it would normally enter the spider and checked pressure at the schrader. It zoomed to 80psi and held 60 for at least 20 minutes and is still showing 50.

Quote from the article:

If the fuel pump is OK, the next thing to check would be the fuel pressure regulator. When the key is turned off, the pressure in the fuel line should hold for at least five minutes. If the pressure drops off, the fuel pressure regulator or fuel pump check valve may be leaking. If pinching off the fuel return line produces the same results, the problem is the check valve in the fuel pump (replace the pump). If pinching off the return line stops the pressure loss, the problem is a leaky regulator.

So I think this means my brand new spider is defective in that it is allowing fuel to flow back to the tank all the time thus no pressure is maintained. What I'm not sure about is if it could be an electrical rather than mechanical issue.

The article states:
The MAXI injector can also be tested with an ohmmeter. The resistance specification is 1.9 to 2.1 ohms, and the coil voltage should be 3.3 to 4.8 volts.

the resistance between the two connectors on top of the spider that hook up to a harness under the plenum read a high of 1.6 ohms resistance. Im not sure how to test the coil voltage but there is a constant voltage of just over 5 at the harness.

I'm tempted to just replace the regulator at $45 rather than put a whole new spider in and find out my electrical system for some reason is blowing up the spider.
 
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