Thanks so far for the help-I have cleaned the EGR, throttle
body and IAC with the help on this board. I want to take the
plenum off and saw the thread describing this for a blazer. I have a 1999 bravada and my concern is this: just toward the windshield from the throttle body is a 2X2 box with connector andin front of that two metal lines going in with torx bolt clamp. My question is how do you separate this from the plenum or how do you move the plenum with this attached (I suspect these are the fuel lines going into the injectors) I peeked into the area below when the TB was removed but couldn't see any washout areas to explain my fuel pressure leak.

 

The 2x2 box is the connector for the injectors. I just did this on my 2000 blazer. mine had a connector lock tab the needed to be pulled out first. Then I used a screwdriver to unlatch the two tabs that lock the connector, one on driverside and one on passenger side. The connector should pull up and off after the locking tabs are released. The hard fuel lines will pull up and out also, but you need to follow the lines to the back of the motor. There is a bracket bolted to the block that holds them in place that is connected to the lines. Remove the bolt and it will free up the lines enough to move them out of the way. Take the bracket that holds the lines into the plenum off and the lines will pull up and you can muscle them to the driver side. They won't stay, but when you inbolt the plenum, you can move them over as you lift it off.

When you lift off the plenum, the injector/regulator assembly stays on the intake. The plenum has a gasket that seal around the assembly and will lift off. Ipressed on the injector assy while lifting the plenum and it popped out.

Another thing is the main harness that goes accross the motor can be pulled forward so you can lift the plenum straight up. The first time I tried to snake the plenum out from under it. The second timewas alot easier.

 

Thanks a ton for the description. So you just pull up on those
hard lines where they enter into that area in front of the connector box? They pop out?

 

I would not just remove the bolt and not totally remove the lines. I did this once and it was a nightmare to put the lines back together. If you do this, you will bend the lines in the process of removing the upper plenum, making it very difficult to get back into the metering body. Take some time and properly remove the fuel lines from the top of the engine. Either use a 16mm stubby wrench or a 16mm crows foot to disconnec the lines at the back of the engine (the crows foot works good if you can find on that is long enough).

The fuel pressure regulator is located on the back of the metering body and really cannot be seen very well without removing the upper plenum. You can use a mechanics mirror with the throttle body off to see pretty good. You will be looking for droplets of fuel.

About the hardlines where they enter the metering body. They are held in by a retainer plate and a nut. You must remove the nut first, pull the retainer plate out, then the lines can be pulled free.