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I need a vacuum diagrm for 89 bronco

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Hello and thank you for this forum.

I'm looking for a vacuum diagram for an 89 Bronco w/ 5.0.

The 5 plastic lines that come around the back of the right head have been cut and had rubber line put on them. They are not going to the right places. I know this because the smog shop said two of them were giving the wrong type of vacuum signal. The EGR line has constant vacuum and they say it shouldn't.


Can anyone help me find a color coded diagram? Even if it's b&w I'll figure it out. Color would just make it easier.


The 5 lines are colored as follows;

Red X2



Pink or Tan


Thanks in advance for any help.



Here are the lines I'm trying to identify where they should go.

My link


http://i325.photobucket.com/albums/k378/LRCXed/BRONCO/DSC_0198.jpg[/img]"]My link

Edited by LRC

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sorry, I can't get the second link to work. It's basically the same picture with the lines spread out.

I sure hope there is some help here.


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yo Larry,

If no one can give you better info;


Try here first;

Vehicle Emission Control Information (VECI) Decal, Vacuum Diagrams & Calibration Parts List for 88 & UP. On-Line for Free at Ford. Click "Quick Guides" in left panel; Scroll to & CLICK VECI Labels "Provides Vehicle Emission Control Information (VECI) and a related calibration parts list." Enter applicable info (need to know your Calibration number from your B-pillar sticker). Vacuum Diagram is the same as the one on the core support or hood or air filter cover.

Source: by Ford motorcraftservice.com



Then look @ the Vac Diagram and compare colors to the compents on the diagram


Vacuum Line Acronyms & Color Codes

Source: by Steve83 (Steve, That dirty old truck), Seabronc (Rosie, Fred W) & miesk5 at Ford Bronco Zone Forums http://broncozone.com/topic/20203-egr/page__gopid__106496entry106496

an excerpt of just some colors:

Red = Main vacuum (from intake manifold)

Green = EGR function

Orange = Heat control Valve (exhaust & intake) (AKA heat riser but more complex)

Yellow = Thermactor Air Diverter Solenoid (TAD)

White = EGR vacuum (source)

Black = Mainly used for the Evaporative emissions control

Black = Thermactor ACV or Diverter valve

Blue = Throttle Kicker control (miesk5 note ?)

Pink = Thermactor Air Bypass Valve (BPV)


next is to go thru the Emissions Section in my site and look under the various sections for the info;



such as;

Air Injection (AIR), Secondary Air Injection; Pump (Smog Pump), Thermactor Air Bypass (TAB) & Thermactor Air Diverter (TAD) Solenoids; Diverter, Check & Bypass Valves, Cross-Over Tube, etc.



Secondary Air Injection system consists of a belt-driven Air Pump, single or dual AIR Diverter valve(s), an AIR Bypass valve, and AIR Bypass solenoids, air silencer/filter, Powertrain Control Module and connecting wires and vacuum hoses. The Belt-Driven Secondary Air Injection system provides either upstream/bypass air or upstream/downstream/bypass air. The number of these system configurations vary significantly with AIR Bypass and AIR Diverter valve combinations (Figure 179). 2. The PCM provides one or more signals that enable one or more AIR Bypass solenoids. 3. The AIR Bypass solenoids control one or more AIR Bypass valves and/or AIR Bypass Diverter Valves in order to route secondary air depending upon the specific configuration. 4. The belt-driven Air Pump is operational any time the engine is running..." read more

Source: by Steve83 (Steve, That dirty old truck) at http://www.supermotors.net/registry/media/589993


here you'll see aa diagram shoing color codes such as PINK, Thermactor Air Bypass Valve (BPV)

and RED for Main Vacuum from Coffee can to Intake, and so on



Location pic in an 88 5.8; "...TAD/TAB sensor located towards back. both connectors are slightly different so once again only plug into one place..."

Source: by Travis L (kemicalburns) at http://www.supermotors.net/clubs/superford/registry/media/157925


"...The Pink Vacuum Line goes from the TAB Solenoid (driver's side rear solenoid) to the passenger side (adjacent to the Vacuum Reservoir Can) and down to the bottom of the TAB (Bypass) Valve. Note that my Pink Vacuum line appears Yellowish in this pic and is not yet connected to the base of the TAB Valve as I was working up a solution at the time.

Vacuum Diagram in a 90 5.8

Source: by Seattle FSB (SeattleFSB) http://fullsizebronco.com/forum/showthread.php?t=170303

Edited by miesk5

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Thank you VERY much. I'll get the bronco back and take a look at the links and info you provided.

Unfortunately the decal showing the diagram is missing on this one. That's the first thing I checked for.


I'll give you an update when I get it here and fixed up. Hopefully it passes smog this time.


Thank you,


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yo, yw & thnx to those who posted that info on the www!


Vehicle Emission Control Information (VECI) Decal in the link I posted is the same vac diagram that was on your Bronco.



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Thank you very much for your help. I followed the list on one of the list for colors and location. The Bronco passed smog with flying colors.

I couldn't have done it with out your helpful links to the info.



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yo larry,



And I am glad you were able to get it passed!

I just got my 96 thru again with no problems, which as you know is another + thAng that makes the day better.

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