Closed Loop/AC ON?

[VetteMed]

That looks like a very good price for those!

[Funracer]

I spent a long time today putting a new set of Accels into the
secondary position. Accels were put into the primary position about three
years ago.

When I got the plenum off I found this:



Not good. It was the tube that comes out between the right rear
plenum gap. Notice the zip tie that I had put on years ago. I pushed
it back in and put another ziptie on tightly:



Warning! Car porn ahead:



I have not pulled the plenum in about 8 years. I don't mean unbolt it
and tilt it up with a 2x4. I mean remove it in order to replace the fuel injectors. The difference is important because removing it completely
adds difficulty and reinstalling it becomes much harder, especially if you are by yourself. Here is why:



I left the socket on to accent the problem. There is a small bolt there that locks the canon plug to the underside of the plenum. The wires run into the plug are quite short - no slack, at least on my car. That makes it difficult to lift the plenum much more than 45 degrees or so. Thus the 2x4 for some applications.

However, to completely remove the plenum this plug needs to be unscrewed from the underside. Due to very limited acces it is tough to
get at. The hard part though is putting it back on. It took me about
2 hours to completely remove the plenum. Another hour to remove
the fuel rail and replace the original (1991) Multitecs in the secondaries with new Accels. Notice the two different types in this pic prior to FI replacement:

[Funracer]

Continuation:

Once I got the new FI's put in I had been at it for awhile and was starting
to fade. But I figured that reassembly would be quicker so I pressed on.

I put the fuel rails back in and began to reinstall the plenum. I soon found that the under plenum connector would not stretch to the plenum in the
"up" position. I dropped it into the "down" position and after some wrangling was able to get the male and female halves lined up by reaching around the back of the plenum. I turned the socket (see previous post for pic) but could not for the life of me get it to thread in. After trying
for 20 minutes, I gave up and tilted the plenum up again. I rerouted the plug wires over
the top of the tube as shown. Compare to the photo in previous post:

[Funracer]

I was then barely able to press the coupling together and get the bolt
to thread on. All in all it took me over a hour just to get that stupid thing
back on to the underside of the plenum and then continue with putting all the rest of it back together. All told the entire project took 7-8 hours and flat wore me out. My back in killing me.

The end result? No change in my idle problems. Changing the secondaries was a long shot but no $$ wasted as they were shot anyway.

I remebered as I went that I had similar issues when I did this years ago.
If anyone knows a trick to make this part easier I am all eyes.

Sorry for the multiple post. It would not let me put it all in one.

Tired

[VetteMed]

I feel your pain. I curse that 1/4" bolt on the large connector every time I pull the plenum. I've found it's easiest when you scoot the plenum forward a little bit to allow access with a 1/4" drive ratchet via the RH side. There's a little room to get in there if you scoot the plenum forward a bit.

As for that vacuum hose, I usually use some rtv adhesive or silicone adhesive to hold the tube into the rubber elbow. I've gotten through an entire plenum R & R only to find that those vacuum lines came undone during reinstallation.

If you have access to a mityvac or other vacuum pump, pull the connector off the RH side of the plenum (between the middle sets of runners) and see if you can pull a vacuum. If so, your connections are OK. If not, you've got a leak.

[Funracer]

Originally Posted by VetteMed

I feel your pain. I curse that 1/4" bolt on the large connector every time I pull the plenum. I've found it's easiest when you scoot the plenum forward a little bit to allow access with a 1/4" drive ratchet via the RH side. There's a little room to get in there if you scoot the plenum forward a bit.

As for that vacuum hose, I usually use some rtv adhesive or silicone adhesive to hold the tube into the rubber elbow. I've gotten through an entire plenum R & R only to find that those vacuum lines came undone during reinstallation.

If you have access to a mityvac or other vacuum pump, pull the connector off the RH side of the plenum (between the middle sets of runners) and see if you can pull a vacuum. If so, your connections are OK. If not, you've got a leak.

Plenty of cursing here as well. Mine was mostly directed at whoever
designed it that way to begin with. I do have a Mityvac and will check
as you suggested.

My next step in troubleshooting is to clean all the grounds I can find.
Will update then.

Thanks