Well I just installed the new gastank, sending unit, relay, and pump, and she wont fire for me. Had it towed home friday cause she just quit. When she quit the fuel pressure gauge was reading 50psi and holding while I waited for the tow truck. When it quit, it was having random problems of just dying and restarting fine over the past couple weeks but I was able to restart it just fine once I stopped. No popping or banging when it happens, just stops.

Now I get about 62psi when the key is on, this new pump is louder too, pressure holds
My NOID light shows the injector signal at the harness connector at the front of engine pulsing properly.
My fuel gauge is dead accurate through all the range! (watched it live as I filled her back up from the jerries)
I have spark at the plugs, and from the coil.
I have no OBD codes
I cannot smell any fuel around the exhaust pipe when Ive been cranking it a while
It does not even spit and sputter, no firing.
Didnt want to fire with carb cleaner in the intake, I dont have any ether to try

I am about to head out and pop the plenum off it once again, and have a look at whats going on inside there, I have a feeling my injectors just not firing as I do have a used spider unit in there with under 10,000km on it from me. I want to pull a leg or two out of the holes and look for myself to see they spray... Any ideas?

 

Having same problem, let me know if you find an answer.

 

I got it Rick. I opened up the plenum to have a look since I narrowed the problem to inside there, and it doesnt look much different than I left it, I had it pretty clean when I changed out spider and injector harness.


So now I wiggle that injector harness and it is not tight like it was when I installed it... Hmmmm how can I tighten that up??? I used 2 small O-Rings on each pin so that you really have to snap the harness on good and its solid as a rock now, more so than when I put it on new less than 10,000km ago. Took her out for an hour run and have had no problems mashing on it, or cruising. I think I got it. See the Orings on the pins?


Sometimes that little rubber insert on the harness is rotted out after years and the connector flops around and makes it not run, try this trick Rick and let us know how it works out for you. You can buy that harnes as well for under 10 bucks at the parts place.

This makes 2 times - Both times - that I have had to tow this beast home cause of this sloppy part... I am going to figure a permanent fix and post it up when I do... I think what I will end up doing is get 2 of those inserts, and cut them in almost half, so that when I stick both halves together it is a thicker unit than the original one and will have to be pressed on really hard to get it to lock...

 

how much was the Sending unit and pump? I never got around to doing mine. But I didnt forget to tell you the price of it down here. I will once I get it.

 

I paid about 50 bucks each.

 

wow thats nice, I priced mine and there about 100 for the pump and 75 for the sending Unit.

You went to Napa right? Could you tell me the part numbers you used, becuase I have 3 different pumps to choose from and I'm not sure which one is right.

I have a 94 4.3 "W" Jimmy.

 

hey Thomas (or anyone else that's on here right now), off hand, do you happen to know what the required pressure is for these early W-codes? is it the same as what's needed for my 2nd gen Blazer?

since you know i'm having the same kinda issue with my brother's Dime (you replied HERE), i'm reading about 53/54 psi @ the valve @ key on. when it starts (& runs for a bit) i'm reading about 55, and if i keep it running (light throttle) the pressure gauge will go up & down with the reving of the engine.

i'm now thinking it might be the pumped crapped out while we got the sending unit rebuilt.

ideas?

***EDIT*** i also forgot to mention that the pressure is dropping (quite noticably) when the engine dies or is shut off. like maybe 8 to 10 psi over 20-odd seconds.

 

Still have not crapped out once since the O-ring fix. The tank and pump probably were fine just rusty and old, I changed them anyways for peice of mind.

Running pressure is about 58 minimum from what I have read.

Mine puts out about 62 now and only has minor fluctuations with the throttle, like 1psi either way. It is electric, it shouldnt change pressure with the RPMs.

Im telling you guys to inspect those harnesses with a microscope, there is these 2 wires up in each lead that are thin as hairs, they have to be PARALLELL or else the connector is broken up inside, and its gotta be tighter than an AllStars shoe-laces when its snapped on the injector. You may also want to try a couple junkyard regulators too and see if you get a change. The pump is obviously working, but if the spring inside the regulator is weak and wont let it build up the 60psi needed, then the reg would be shot methinks. The excess pressure and fuel are dumped back into the return line. 55 might be enough to run, but its not enough to win the races. An FPR was like 90 bucks when i got a new one and i have a couple junkyard spares that I pocketed while cruising the junkers.

Check my build thread in my sig for part numbers. I purchased the tank and sending unit from ProBody Parts in Edmonton. They ship and have warehouses allover west canada. I got a good deal on them cause my brother used to work there but call them anyways, you never know. Try the Oring fix, its 2 on each pin, I think the size was T03 or something. they stretch a little onto the pins.

 

just got home a few minutes ago Thomas, and it turns out there were more forces working against us, than with us.

turns out my buddy's fuel pressure gauge was acting funny-out of calibration & won't hold a proper reading. i stopped by his shop while he was out, and i picked up the wrong kit (didn't even know he had more than one kit!), so i rechecked it, and it's good.

64 psi @ key on, 61 running.

as for the cost of the injector parts ($380 for the FPR/injector/fuel return lines to be expressed overnight from California!) that was unavoidable since he realized on Thursday last week, that he hadn't bought a replacement yet, and i was putting the engine back together on Saturday & installing the driveline.

so he had to have it rushed.


the sending unit & tank, that was all rebuilt, since it is a show truck. besides, i don't pay retail for anything automotive related.


unless it's after 1:30 on a Saturday.

 

Do you have a link to where you got that injector harness ? Either Im too stupid or no one has any where I have looked. Thanks