Hello,
I have a 1989 4.9l Ford. I can not seem to figure out where the BLACK vacuum line going to the "TAD" (thermactor Air Diverter) solenoid is supposed to be coming from. Judging by the length of the line it is someplace near the number two intake runner, but I can't find the port. Can anyone help?

 

Do you have an emissions decal on your radiator support? Should tell you everything.

 

I have referred to the vacuum line routing sticker and it isn't enough for me. Anyone with a stock 89 out there that could take a look at theirs?

 

Here is another cry out from me for help. Anyone with a stock 1989 4.9 out there who could take a look and perhaps a picture of where this black vacuum hose routes to in the vincinity of the #1 or 2 intake runner? I have looked at my engine as best I can and for the life of me I don't see a bare nipple for this baby to attach to.

 

if its from the solonoid then its to the smog pump

 

Thanks for the advice. I will give it a good looking at. The way this nylon line is bent it seems like that would be out of range for it, though.

 

May be the other part of that line is missing. If the soliniod your talking about is located on th left side of the engine near the rear, there should be 3 correct? Two rear most are for the smog system one controls tge air to the heads the other for the exhaust pipe right? There should be vacuum for the fuel preasure regulater on the fuel rail near that area but that is manifold vacuum. Another for the purge vave soliniod that is mainifold vacuum too. Thats also near the area your talking about

 

The "TAD" solenoid is the middle of the group of three vacuum solenoids that is mounted to the driver side rear of the valve cover.

There is a hard black vacuum line running from this solenoid around the back of the valve cover to the passenger side of the engine.

It is routed in the bend between the upper and lower intake manifold halves.

It terminates with a rubber boot meant to slip over a nipple someplace. I can't find the nipple though! I will check out the air pump. It is very close and perhaps the line had been unhooked for quite some time and took a set different than it should be.

 

From what im looking at... The middle one is tab. And it goes to the rear most valve on the thermacter assy. After that bit of info all i can say is good luck or bring it to the house and we can get it

 

Well I looked at this more today. I found that the vacuum line going from the manifold tree to the driver side vacuum canister (this truck is the "calibration" that has two vacuum cans) was tee'd. The other line off the tee was going to the divertor valve portion of the air control valve. In other words, the divertor valve has been subject to manifold vacuum for who knows how long.

The line that should have been connected to the divertor valve is the black nylon line that had in fact been lying disconnected nestled in the intake runners.

Once I figured this out I was pretty happy.

Unfortunately, the divertor valve diaphragm must be ruptured because it will not hold a vacuum. I will be looking for a good valve the next time I visit the junkyard.

Thanks for the help. I guess I was really thrown by assuming that nothing on this pickup had been modified in the past. If I had the notion that there was an extra vacuum line, I think I could have figured it out a long time ago.