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Also check the vacuum line to the fuel regulator. It’s at the end of the fuel rail and regulates pressure for the injectors in the rail.
If the regulator took a dump, it could be sending fuel back to the tank and causing low pressure at the injectors. Not a common failure but worth a look at the regulator and it’s hoses.
 

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Discussion Starter #22
Richy04, Will check those again but they look ok. Again, I can get the pumps to work by jumping relay but the pumps won't shut off doing that and car will only run for a few seconds.
 

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Richy04, Will check those again but they look ok. Again, I can get the pumps to work by jumping relay but the pumps won't shut off doing that and car will only run for a few seconds.
that is correct. Jumping the relay makes the pumps run continuously...jumping is just to test things.

My next test would be to undo the fuel line that comes up to the injector rail, then turn on the ignition with the relay jumped....does fuel flow?
Yes?
then it is getting to the rail and the lines from pump to rail are good.
No? blocked lines

Next you need to find out why - if it is getting to the rail - it is not getting into the cylinders.
1. Pressure regulator, like richy suggests...any raw fuel in the little vacuum hose and the P.Reg has failed...the hose too needs to be good, not split.
You could try clamping off the return line coming off under the P.Reg....see if that makes it run a bit longer.

2. Injectors not firing: do they have voltage at both pins? are they getting a signal (noid light test)
(the car 'running just a few seconds' could just be cold start injector fuel.....that will work independant of the injectors)
 

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Discussion Starter #24
spiderseri4, Ok, will check to see if fuel to rail with relay jumped. Just tested continuity from coil to pin 1..excellent.
 

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Discussion Starter #25
Good Lord! I disconnected the fuel line from the rail, put it in a soda bottle and got nothing when I jumped main relay or pump relay(pumps were running). BUT, I did get a good flow of gas from the fuel pressure regulator where I disconnected the gas line. Fuel going backwards? What the heck? How does that happen?
 

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Discussion Starter #26
Dum me. Wrong line disconnected. I would have thought the feed was to the fuel pressure regulator. Should have double checked the diagram. Well, I know that fuel is getting to the rail when I jump the relay. Should it come flowing out the regulator?
 

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Out the regulator's small hose that connects to the intake plenum? NO! That is the vacuum control hose. When intake vacuum drops the regulator increases the fuel pressure in the fuel rail a few psi - so the injectors squirt extra fuel on acceleration.

Fuel should come into the fuel rail at pump pressure, the regulator controls that pressure by sending any excess back to the tank via the return line. If the return line is blocked the regulator cannot control the fuel pressure. If the supply line is blocked there won't be adequate pressure to supply the injectors. If fuel is coming out the vacuum side the regulator's internal diaphragm is faulty.
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Discussion Starter #28
Actually it was coming out the return hose not the plenium vacuum hose because of my dumb mistake. I did suck and blow through the vacuum hose and no air either way. I have not check for a blockage in the return hose. Will do next. Right now the car is sitting in the hot sun and both of us are fried.
 

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Discussion Starter #29
Just blew out the return hose by placing it in a plastic soda bottle in the trunk and disconnecting from fuel pressure regulator using 110 lbs of air. Blew the plastic bottle across the trunk. No blockage there! At this point I'm at a loss for what to do until the new main ECU relay arrives. This car has run flawlessly for 5 years. I bought it in Virginia and drove it home to Massachusetts without so much as a hiccup and it's been driven without issue until now. Help!
 

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wait for the main relay ....but I think your fuel (Drive) relay will be bad too....
you said earlier, the pumps don't work when you turn the key to "START" but they do when you jump #30 & #87 of the Drive relay ...normally that is a sure sign that relay is bad.
drive relay wiring.JPG

in the mean time keep your battery on charge because all this testing will run down the battery and if your cranking volts are not about 10.5-11V then nothing will work.
 

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Discussion Starter #31
I'm keeping battery charged. While waiting for the relay I'll be cleaning more connections. The only thing I haven't diagnosed is the air flow meter. May see if I can figure that out. Running out of options and a lot of head scratching but I'm determined to find this as well as learning the system.
 

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Lots of good hints here. I will add my advice. If you do not have, purchase a small inline fuel pressure gauge to "T" into the fuel feed hose at the rear of the fuel rail. Energize both fuel pumps by jumping relays, or simply by using jumper wires from a good battery source. Ignition does not have to be on. With both pumps running, everything connected (of course), fuel pressure should be about 35-40 psi, with the fuel continually circulating to the rail, and back to the tank. If good, the fuel delivery to the rail and injectors is good. Let this run for a few minutes to check all connections, etc. Then, using a NOID light (google it, inexpensive) on an injector wire connector, and an inline spark checker light (same), making sure that you have a FULLY charged battery, have an assistant crank the engine. Look for the noid light and the spark light to flash. If one or both are not flashing, you have other problems. If fuel pressure is good and both lights are flashing, it should start. If not, check compression and spark plugs. Good luck!
 

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Discussion Starter #33
andylarry, Yes I should check fuel pressure after I purchase a gauge. As far as injectors, it'll run for 4-5 second then quits. So I kind of eliminated injectors not working...I think.
 

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Discussion Starter #34
To my thinking, it seems to be the transition from ignition powering pumps to ECU taking over after starting is detected. Thus the start for a few seconds and then stop.
 

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It could be running on the cold start injector for that 4-5 seconds. That's why it would help to have the noid light for the main injectors. Get the tools, use an assistant, monitor the tools as it cranks and begins to run. Harbor Freight should have all that you need.
 

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Discussion Starter #36
The NOID light test sounds good. What if the injectors are not firing? What is the most common cause of injectors not firing? Thanks andylarry.
 

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Good question. Flywheel sensors, wiring / connection problems, ECU... Eat this sandwich one bite at a time. Get your fuel pumps running at proper pressure first. Then check for good spark, and good signal to the main injectors. Keep in mind that you need a FULLY charged battery that holds above 10v WHILE CRANKING to get the ignition and fuel ECUs awakened.
 

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one thing to test (while waiting for the noid to arrive) is to see if the injectors even have voltage....
pull the connector off one of them and test one of the pins to ground (key on) then the other pin....got voltage on both?
 

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Discussion Starter #39
Will test injectors when it stops raining here. As I mentioned earlier, when I tested for gas to the fuel rail I made an error and pulled of the return hose from the fuel pressure regulator and got a lot of gas coming out from the return end of the regulator. After looking at gnhl post of the cutaway regulator, I'm wondering if the valve is stuck open. Just thinking that I shouldn't be getting the much return gas.
 

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After looking at gnhl post of the cutaway regulator, I'm wondering if the valve is stuck open. Just thinking that I shouldn't be getting the much return gas.
One of the reasons I suggested clamping off the return line to see if it’ll run longer
 
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