Do you smell any fuel at all? You may wanna pull the plenum for ****s and giggles just to see if the spider assembly is in good shape. Typically, these setups get hard and crack with age. Sometimes, it's hard to determine the issue until the is a big breach in the spider lines. Also, I would verify whether or not the timing is set properly.

 

No, no fuel smell that I have noticed. I'm thinking that's probably the next step is to just pull the plenum off like you said and look at the spider assembly. This truck had definitely been sitting for at least 5 years so things getting hard and cracking is a very good possibility. I didn't think of checking the timing, but that sounds like a good idea. Thanks for the tips. Hopefully next time I post back here I will have a better idea of what's wrong with it.

 

Hey man, good luck, and keep us updated. We will whiddle down the problem til it's fixed...

 

yes. watching eargerly.

i had spider injector replaced, and that did the trick. but my symptoms were not as yours are. it would run, but then stall out and become flooded.

fuel pressure regulator or the injector is all i can think... and the timing as was suggested.

good luck!

 

is there no fuel geting up to the engine at all? even with a leaking injector fuel will get there, just not hold much pressure for long. Also the other problem with that is a leaky injector/regulator will usually run, if it is to the point where it wont then it's flooding the engine and starter fluid sure as hell wont help. Get a fuel pressure gauge and see what is says when the key is cycled. Inspect all fuel lines for kinks and leaks, make sure the lines are connected right on the pump. If it checks out then the regulator may just be leaking internally and simply not holding pressure from returning to the tank.

 

Thanks for the support guys. I will try to address your questions, let me summarize what I've worked on since my last post.
Last weekend I didn't have a chance to get a fuel pressure gauge but I wanted to make some progress so I pulled off the air intake manifold to get a look at the spider injector. There was a bunch of dirty oil and gas collected in the bottom of the manifold area where the injector is. I pulled it out and pulled out the six tubes from it. I hooked each one up to an air compressor putting out 60 psi and each poppet valve opened up so I know they aren't gummed up. After talking to my local mechanic this afternoon he said it sounded like the regulator in the injector had gone bad and that I would need to get a new one. He loaned me a fuel pressure gauge so I could make sure the new fuel pump was putting out the right pressure... unfortunately after getting it home I realized it wasn't working properly. It's a Snap On model number mt337a (google image search shows pictures of it) and the pressure release button seems to be stuck open or something because when I hook it up to the schrader valve on the fuel line, as soon as the pump turns on gas comes out of the gauge relief tube, so it never builds up pressure in the gauge. I'll see what he says about that tomorrow morning, but I have a feeling it's a moot point anyway if he is right about the regulator being bad.

As for checking the timing, I haven't messed with that, and here's my reasoning: The engine sounds very good when its running on starter fluid, and I figure that while the timing may very well possibly be off, it's most likely not my biggest issue right now. Once I get the fuel issue resolved then I will make sure that the distributor is in the correct position. Of course I may not be seeing the whole picture here and if I'm missing something about that please let me know.

Inspecting the fuel lines again certainly isn't a bad idea, I went over them pretty good when I took out the gas tank and replaced the fuel filter but it never hurts to recheck.

Again, thanks for the suggestions guys, yall have been a great resource and support.

 

did you see any washing on the intake under the plenum? (gold coloring on either side of the fuel injector)

and that is kinda scary knowing your mechanic had a tool that was not working right.

 

mine had fuel puddled in the bottom of the plenum bowl as well.

gold coloring too!

it runs great... for a 400xxxkm beaut.

 

Hey folks. So I'm really kicking myself right now... I realized I installed the wrong pump. The ACDelco EP386 pump is apparently for TBI vehicles- puts out about 12 psi, which is exactly what mine is doing (finally got ahold of a working fuel pressure gauge). So I looked it up on ACDelco's website and they say I need the EP381, which should give me about 58 psi (needed for CPI Blazers). Man do I feel dumb right now

Well, went ahead and ordered the CORRECT pump, should get here sometime this week and then I have another day of crawling around under the Blazer searching for my marbles to look forward to.

On a better note, hope everyone has had a happy Mother's day.

 

Bosch makes a stout pump for the vortec as well.