What's the easiest way to make sure gas is getting to the injectors? (4 Viewers)

[e9999]

Had the 80 in storage for some time. I had emptied the tank with the fuel pump so there was very little gas left in the tank. I just drained the old gas that was left (less than a quart, turns out) through the drain plug and rinsed the tank several times until there was no longer any dirt coming out (not much at all overall). Put about a quart of fresh fuel in. To my amazement, it started after only a couple of seconds of cranking. (I had cranked the engine first with the EFI fuse off first to get oil to flow everywhere.) It was idling beautifully and did so for several minutes and then stumbled and died. I figured there was no longer enough fuel in the tank, unsurprisingly, so added another quart. It started fine again right away but some minutes later stumbled some more and died. It does show the maintenance light on when it dies, FWIW, but no OBD error code seen. Added some more gas but no go, it cranks fine but won't start now.
Given all that, my first thought is that there is something going on with fuel availability. Perhaps there was dirt left in the tank after all and either the sock or the fuel filter got plugged. Or maybe the sock disintegrated. (Or maybe this has to do with the EGR since I had an intermittent code about that earlier.)
I do vaguely remember that accessing the fuel filter was a pain the last time I did it.
So, I want to see first if gas is actually getting to the cylinders.
What is the easiest way / place to find out if fuel is delivered properly? Are the injectors easy to remove and observe? Or can I tap easily somewhere useful downstream of the fuel filter?
Thoughts?
TIA

 

[LongDuck]

How much fuel did you add to the tank? I would think a quart of gasoline would not go far to fill the Fuel lines, the return line and the pump - but you said it ran fine.

Recall that the pump is cooled by the Fuel, so might be a good step to throw a few gallons in there and see what happens. Apart from that, the #1 Fuel Injector is easily seen from the front of the engine and an old mechanics trick is to take a long screwdriver and hold the blade against the body of the injector while you hold the handle to your ear while someone cranks - you should hear it ticking if it's firing. (*take off your tie before trying this...). Or, a mechanics stethoscope is far easier for this kinda work.

If it ran before, I wouldn't suspect fuel flow issues unless as you say it clogged up the filter, but these Fuel Filters are large for a reason, as contaminated fuel and low quality fuel are in the design consideration.

 

[e9999]

ah, good point about cooling the pump, I do remember it being a bit higher up than the sock. Although you would think they designed it to work with low tank contents, so it may be primarily cooled internally. I did not want to add more fuel just yet because it becomes more of a pain to drain it then, but it may come to that. I'm also not particularly eager to open up the top of the tank TBH.
I do have a mechanic stethoscope that works very well. But would I hear the fuel going through or just the ticking when it's actuated?

The more I think about it, though, the more the stumbling sounded like when you kill the engine with the EGR during a smog test... And I have bad vibes with that EGR already, so...

 

[cruisermatt]

You're way overthinking. Just slip the return hose off the fuel pressure regulator. It's right on top of the engine.

Have a helper cycle the ignition on for a few seconds, leaving engine off, while you watch, gas should stream out at low pressure.

 

[e9999]

yes, good point, that is sort of how I emptied the tank in the first place. I used a separate power source then IIRC, which was a pain so I wanted to avoid that to start with, but you are right, in this case it would only take a few seconds to check if fuel is coming through, so no need for a separate power source. Easier. I imagine seeing some gas come out on the return side would mean there is enough pressure at the injectors if the FPR is doing its job.