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740 No Pulse to Injectors, Has Spark

PromiseRing said:
I?m not saying your ECUs are for sure good, but the odds of 2 very reliable ECUs both being bad is very slim. Unless of course they were thrown in a pool or something?

Also, the fuel pump relay is easy enough to swap out, have another laying around? Takes about 30 seconds. Try a couple different ones.

But also if it for sure doesn?t start on starting fluid then you have issues. Are you 100% sure the engine is timed correctly?
Click to expand...

I am not. I haven?t messed with the ignition timing since putting back the distributor after replacing the hall sensor. As for the cam and crank, they are aligned.
I have one somewhere, but I don?t think it?s good. I?ll have to grab another fuel system relay to have as a spare. I have 3 for my P80s.

I had the same thoughts about my ECUs, but the discrepancies between the readings lead me to believe it may be an issue. But the fuel relay-related issues are probably not ECU-related.
 
Hm maybe try putting the distributor right in the middle and see if it starts off of starting fluid. I’ve never messed with 2.2 but I’m pretty sure you can just adjust ignition timing like normal right? Not so much the case with 2.4.
 
If it’s timed correctl, getting spark, has compression, no reason it shouldn’t start off of fluid. You should disconnect the AMM when starting off of fluid, and spray directly into the TB
 
I'll mess with the timing today between these Florida style pop-up storms we've had non stop. I should be able to get it running on starting fluid.
 
Tested once again for injector pulse while using a Y-jumper on the fuel relay, and I now have pulse!
Next problem... I do not have fuel at the rail. I pulled the return line from the fuel pressure regulator and there was nothing. I went ahead and changed the coupler line between the pump and filter (it was kinked, had a new one on the shelf), and there was no fuel at all there either.
I don't think my in-tank pump is running. Wouldn't the in-line main pump have enough power to pull the fuel? I checked and there is voltage at the connector for the in-tank pump, so I'm pretty sure it's dead.
 
Yes you can run a car with just the main pump. If you get a pulse using the y jumper, shouldn’t you have a pulse using just the regular fuel pump relay? Possible bunk relay?

Make sure fuel is in the car. Also, Idk if you should forsure have fuel on the other side of the regulator. It’ll only ‘open up’ if there’s enough pressure. How about busting the feed line loose at the rail and seeing if there’s fuel. Also, it should really be starting off of fluid lol
 
Do you know how I get a full sized truck with a dead fuel system into the work bay? A wheel man and a guy under the hood spraying brake cleaner into the throttle body.
 
Something's probably up with the relay. I don't know, maybe it's because I swapped to my newer ECU again and I hadn't checked for pulse with the relay.
I get it, starting fluid... I just adjusted the timing, I'll see if it starts today.

Like I said, there is no fuel getting through the lines to the rail. When I changed the fuel line between the pump and filter, it was bone dry.
 
Turns out the in tank pump is running. The problem was my “assistants” being deaf...
According to the gauge, there is gas. I put a couple gallons in a while back, and they have not leaked out. Maybe there just isn’t enough gas? Which seems odd being that there’s probably 3-4 gallons in there.
 
Freaking fuel pump assembly looks like crap. Everything’s rusted and the fuel level sender portion seems to come apart into two pieces. I had the impression it would be a float on an arm, but I’ve seen differences before with this stuff.
Now I’m debating tracking down a full fuel pump/sender assembly, but I’ve got no clue where I’m going to find one for a reasonable price.
 
Found a LOT of junk in the pump itself and the outlet line from the pump. I ended up just putting in the new Pepboys pump I grabbed this morning and cleaning up the lines on the fuel sender assembly. I probably could have reused the old pump, but with how much dirt and nasty stuff was in there, it made more sense to just replace it.
I had to use a straight fuel line instead of the accordion style hose that was there (it broke, and had a cut in it already) for now, but I plan to upgrade the fuel pump relatively soon after it's running so I'll change to the proper hose then. This car won't be a daily, so I'm not too worried about the fuel gauge not working temporarily.
Also, for some reason, there was no sock on the bottom of the old fuel pump. Maybe it fell in the tank? Or maybe someone
replaced the fuel pump previously and never put a sock on.
 
I'm going to go fishing for it tomorrow. I need to remove the gas first though, it's a nice rust color and smells like turpentine.

If it doesn't start after all this, it's going to find itself at the bottom of a cliff.
 
The small fuel line in the tank won't last more than a year or so if you didn't use submersible fuel line. I've done that but nowadays regular fuel line should be avoided if you can. Or just know that it is temporary. It's even more important these days since we have alcohol in the gas which eats up the rubber faster than just gas would.
 
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