Working on a 2000 pickup with the 5.7 Vortec fuel system. New upper intake and MPFI injector assembly.
New engine threw a couple codes the other morning, lean fuel trim on both banks. Looked under the hood and found a vacuum leak between the metering body and upper intake. Thought maybe I didn't get the body seated properly when putting it together. Tried pulling it up some but could see the o-ring was twisted and starting to come off. Took it apart, o-ring fell off and looked like it had got pinched. Put a new one on it but still have an issue.
So I put the gasket on the metering body and lay the intake on top. Upper intake is only like 1/8" above the lower mounting surface. This doesn't really give me enough room to work it down onto the gasket but is still too high up for the intake to lay flat. The same thing happened when I put the intake on the last time, and I just let the bolts pull it down. But I think this might be what caused it to leak. When everything was assembled there was maybe a 3/16" gap between the top of the metering body flange and the bottom of the inner lip of the intake. I compared it to another vortec engine and the gap on that one was smaller. I think my metering body is sitting too low in the intake and not making a good seal.
Been looking at the old and new parts trying to find any differences. Thought maybe the injector bracket was bent or something and got a new ACdelco one. It was identical to the old one. Compared the old and new upper plenums and they seem to be the same height. Can't check the old injectors as I sent them for a core but I remember they looked about the same. Not really sure what else to do other than try to shim the bracket up a little higher. Maybe use a longer bolt too.
Anybody have any tricks, am I missing something?
New engine threw a couple codes the other morning, lean fuel trim on both banks. Looked under the hood and found a vacuum leak between the metering body and upper intake. Thought maybe I didn't get the body seated properly when putting it together. Tried pulling it up some but could see the o-ring was twisted and starting to come off. Took it apart, o-ring fell off and looked like it had got pinched. Put a new one on it but still have an issue.
So I put the gasket on the metering body and lay the intake on top. Upper intake is only like 1/8" above the lower mounting surface. This doesn't really give me enough room to work it down onto the gasket but is still too high up for the intake to lay flat. The same thing happened when I put the intake on the last time, and I just let the bolts pull it down. But I think this might be what caused it to leak. When everything was assembled there was maybe a 3/16" gap between the top of the metering body flange and the bottom of the inner lip of the intake. I compared it to another vortec engine and the gap on that one was smaller. I think my metering body is sitting too low in the intake and not making a good seal.
Been looking at the old and new parts trying to find any differences. Thought maybe the injector bracket was bent or something and got a new ACdelco one. It was identical to the old one. Compared the old and new upper plenums and they seem to be the same height. Can't check the old injectors as I sent them for a core but I remember they looked about the same. Not really sure what else to do other than try to shim the bracket up a little higher. Maybe use a longer bolt too.
Anybody have any tricks, am I missing something?