The Rundown:

1996 Chevy blazer POS edition ( just sick of working on it lol)
4.3 vortec
4l60E
4X4
yada yada yada...........

I have had a lot of trouble with my wife's blazer stumbling running rough and just all around no power. After a new set of injectors, 2 new regulators, a tune up, new filters, fuel pressure parameters verified in the nominal range.

God Almighty I have found the problem.
The fuel injector pod seems to get sucked into the intake and therefore creating a MASSIVE vacuum leak.

Now the tricky part. After 4 sets of o rings and intake gaskets I'm sick of fighting it. There must be a reason it does not always maintain a seal. Do I need to replace the intake? Are there different injector brackets for different intakes?

 

The injector upgrade, (injectors located at the intake ports) requires a new, (different) bracket. The fuel metering block O ring needs to be lubricated with engine oil just prior to installing the plenum. The metering block must be pulled up into the plenum, until it is fully seated. If you omit any one or more of these steps, it will leak vacuum.

 

I oiled them, but is that to say that the injector block, pod or what ever needs to be installed in the upper manifold before it's bolted together. I still have the old style with the injectors in the plastic block and the nozzles plug into the lower intake. I do not have the upgraded injectors.

 

just a side note: It did not leak when I installed it. I ran great for a few weeks. then the engine would intermittently run like crap. So yesterday I was out wiggling thing under the hood I decided wiggle the fuel pod and it stumbled spark knocked and died. I does not always do this.

 

(crickets)

 

The metering block needs to be aligned with the hole in the plenum. After the plenum bolts are torqued, the metering block needs to be pulled up until it snaps into position in the plenum. This why the bracket is made to move around, and not bolted solidly to the lower intake.

 

Ok. I understand it needs to be aligned. How do you pull up on it without breaking it? It never seems to go all the way up. Are we talking pliers and vise grips? I mean thats the problem is getting it all the way up. Sorry to be a hassle but this is the first one I couldn't get to go all the way up. I did a 5.7 in a 97 chevy that wasn't near this much trouble.