This is a simple thing thats driving me nuts for some odd reason. I searched for the better part of an hour and just couldnt find the answer. The vac. line that goes into the rear of the plenum, not the FPR one, but the other. In the middle there is a nipple and I cannot find the line that goes to it, or anything along those lines, can someone please help! Thanks!

 

Its a vacuum line that runs over to the driver side of the car, I forget what all its hooked up to. It should be in a clip thats attached to the center of the cowl.

 

It's probably the vacuum fitting for your heater controls inside the car. The fitting for that is right next to the fpr fitting on the plenum. The only other vacuum fitting is the large one for the brake booster, which is on the driver's side rear of the plenum. The vacuum line for your heater controls should be located somewhere on the firewall/cowl area.

 

Well, I was timing the motor today and had the EGR silonoid(SP?) off since the coil was off and I found a Vacuum fitting on it, which I can only assume goes that middle line going into the plenum. Thanks!

 

The EGR solenoid hooks to a plastic tube that runs under the plenum to a fitting on the driver side bottom of the throttle body.

 

I dont have any pictures, but ill try to explain how Its setup, dunno if its right, I went by the diagram on the hood, but here goes.

The 2 vacuum lines coming out of the front of the EGR solenoid (under the ignition coil) go to the TB and the EGR under the plenum. The Vacuum line that connects to the back of the plenum, right in front of the FPR line, has a nipple connection about halfway back. The only line I have coming from my brake booster is the big one that goes to the back of the plenum on the drivers side. I took the EGR solenoid off yesterday and theres a plug on the backside of it, and what looks like a vacuum line fitting, with a clamp to hold it in. This is what I am *thinking* that the middle connection goes too. But im not real sure.

Ok, this is kinda hard to see, but Ive circled the Vacuum line I am talking about.

 

Let me try to explain this one time for ya. You will either have 3 or 4 vac line fittings, depending on whether you're MAF or Speed Density based. Since yours in an 89, you should be MAF unless it's been converted, so you should have a total of 3 vac lines. This is all based on the standard setup that was on my 91.

You already know the big one is for the brake booster.

The second one goes to the fuel pressure regulator.

The third line is the the one with a check valve and a T fitting. It supplies the heater/defroster/AC directional flow diaphrams, the vacuum operated cruise control, and also goes to the vacuum reserve storage ball under the drivers front bumper cover.

The plug on the back of the EGR solenoid is a FILTER, not a vac fitting. The EGR solenoid only has 2 vac fittings, one to the throttle body and one to the EGR valve.

Hope this helps!

 

Awesome Vernw! I found the line over by the vacuum ball wrapped around the smog canister, sure enough it fit perfect all the way around! Thanks a ton!