I'm starting to tear down my 460 in my 1988 F250 XLT Lariat extended cab with a 4 speed + overdrive manual transmission. I've found a few vacuum lines to be missing. I'm hoping that you guys can tell me where these should connect. One is on a valve/housing that I can't determine. I'd appreciate it if you'd share the name of function.

I ran a KOER test and got codes 41 and 33. I'm wondering if the missing vacuum hose is the source of the 33 (EGR).


Thanks!

PCV



EGR/EVP - the metal tube that runs behind the EGR doesn't have a hose connected. I'm assuming this should flow to the exhaust manifold. I crawled under and looked up and see a plug in the end of the exhaust manifold (located at the rear of it). Is that where it was suppose to go?


Unknown Valve/Unit - This is next to the starter relay behind the battery. The AC on this truck was removed so maybe this is a left over?

 

There should be a Vaccum Diagram on the underside of your hood....It'll tell you where everything is to be placed...


As for the last pic...It vaguely reminds me of part of the SMOG system...Don't take my word to the bank on that though...Looks like some sort of secondary unit for that system...


Thirdly; Welcome to FTE!

 

The vacuum diagram is missing on the underside of my hood. I have the service manuals, chilton's and Haynes and I couldn't find a vacuum diagram. If anyone knows where to find one then I'd be appreciative.

Thanks for the welcome!

 

What's your email address?

I have a Vac Diagram...Not sure if it's for an 88 460...But it might help you some...

 

gregorywramsey@yahoo.com

 

Check your email...

 

Thanks. I'm trying to read it now.

 

Yes, the EGR metal tube should go to the manifold.

In your second pic, there is a green vacum line on the EGR valve. The other end is at the EGR transducer (black thing), but it doesn't look like the line is actually plugged in. Make sure it is plugged in, and make sure the transducer is secured to that bracket that the other solenoid (for the AIR) is clipped to. It takes two nuts. Also make sure the second line is connected to the transducer... the one that supplies it with engine vacuum. There should be two vacuum lines on each of those solenoids.

The thing in your third pic is the intake/exhuast muffler for the AIR system.

edit: Almost forgot, the connector for the valve position sensor isn't connected to the EGR valve. I don't know if you just did that for the pic because your TPS is also out.

edit again: In your first pic, there should be nothing going to that connector. Ford sold two versions of that PCV valve, one was for vehices that had a vacuum line going there. If you look closely, you will probably find there is no hole at all on that connector, but if there is, just plug it up.

 

So here is the diagram.


Here are the keys:
VRESER - Vacuum reservoir solenoid valve
EGR - Exhaust Gas Recirculation
EVR - EGR Regulator
CPRV - Canister Purge Valve
SOLV TAD - Theermactor Air Diverter vacuum solenoid valve
SOLV TAB - Theermactor Air Bypass vacuum solenoid valve
FPR - Fuel Pressure Regulator
ACV - Air Control Valve
MAP - Mainfold Absolute Pressure
MAN VAC - Manifold vacuum (usually a tree on the manifold)

Thanks for sharing but I don't think this is the correct diagram. It doesn't show the PCV unless I'm missing something. I also don't understand where the EGR that routes from the Throttle body ends up. It looks like it routes back to the EVR which in my engine is also on the throttle body.

At some point doesn't a "Exhaust Gas Regulator" have to connect to the exhaust?

Should I post this in then 385 engine forum?

 

That diagram is from a small block. The only functional difference is that the TAB and TAD solenoids on the diagram are a single solenoid on your engine. The diagram won't show the actual exhaust tube from the EGR, it only traces vacuum lines. The EGR line you mention is the green line of which I spoke above.

Edit: Another difference is that the supply to the TAB and TAD on that diagram goes through the reservoir. On the 460, the single AIR solenoid is supplied direct from the engine, with only the EGR coming from the reservoir. That diagram seems to have it reversed.

 

Thanks Peter!

On the second picture, I zoomed in (because I'm not in my garage) and it is connected. I wondered that the black thing was, EGR Transducer, so thanks for that. I also wondered if it should be disconnected. It was tucked behind the coil when I bought the truck a couple of weeks ago. Does it bolt to the valve cover behind the coil or to the coil or where?

As to the TPS and the connector to the valve position, I removed those because I'm getting ready to pull the engine.

And thanks for the info on the PCV having an unneeded stub.

Regarding the EGR tube, do you know where on the exhaust mainfold it should connect?

As to the muffler, so that's as designed, no hose is needed, correct?

 

Nevermind the ? about where to mount the transducer, I see the bracket on the side of the EVP/EGR. I'll look for that 2nd vacuum line.

 

Just to clarify, the two solenoids and coil all mount to the same bracket on the valve cover. Don't use the bracket on the EGR valve itself... that is for some wiring harness. You almost have it right in the pic, just rotate it so it can go over the two studs on the back of the bracket. The EGR should connect to the part of the manifold you mentioned... I was wondering what you meant by having it open, it would be a huge exhaust leak unless someone plugged up the manifold.

 

Thanks again.

The EGR tube is open, the exhaust manifold is plugged as far as I can tell. But would a code 33 happen if the EGR is reading nothing but fresh air? Or is it due to the possible missing second vacuum?

 

Sorry about it not being 460 specific....

That's the only one I could dig up on short notice, from my files on my computer...lol

At least I tried....