Engine Would a disconnected VSS and EGR effect engine function?

evintho · Dec 19, 2020

Like the title says. With no VSS and EGR would the engine still run properly? Would the ECU compensate for that or would it even effect the operation? '93 5.0/AOD.
Kinda vague.....I know!

Dan02gt · Dec 20, 2020

Yes VSS is definite must for the anti stall strategy. It’s also used for cruise control.
The EGR is not a huge deal but will throw the tune slightly off under certain conditions. You can turn it off in a tune.

Mustang5L5 · Dec 20, 2020

VSS would make s difference.

EGR not really

evintho · Dec 20, 2020

Thanks guys! If it makes any difference, I'll have an EGR block off plate on the TB.
Also, on the VSS according to my wiring diagram #679 is the feed from the ECU to the speed amplifier (which I assume is the cruise control) and #676 is the return line. There will be no speed amplifier on my project. Any way around this?

Mustang5L5 · Dec 20, 2020

What are you trying to do?

the VSS is a VR type sensor with just two wires. You just need those two wires connected to the right pins on the ECU.

evintho · Dec 20, 2020

The wires are connected to the proper pins on the ECU. I just need to know what to do with the other ends of the wires being as I'll have no speed amplifier.
Can I just connect the feed and return wires together?

Mustang5L5 · Dec 20, 2020

The ECU and speed control amplifier are wired separately

no need to do a thing. If you want to verify you can check continuity from VSS wires to pin 3 and 6 on the ECU

jrichker · Dec 20, 2020

The following are diagrams courtesy of Tmoss & Stang&2birds

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs

5.0 wiring diagram for Fuel Injectors, Sensors, and Actuators

See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring; http://www.veryuseful.com/mustang/tech/engine/ Everyone should bookmark this site.[/b]

TFI module wiring for 94-95 Mustang GT
http://www.veryuseful.com/mustang/tech/engine/images/Mustang-94-95-IgnitionControlModule.gif

Complete computer, actuator & sensor wiring diagram for 94-95 Mustangs

http://www.veryuseful.com/mustang/tech/engine/images/94-95_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs

http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 88-90 Mass Air Mustangs

http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

5.0 wiring diagram for Fuel Injectors, Sensors, and Actuators

http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

Main body EFI wiring harness

http://www.veryuseful.com/mustang/tech/engine/images/mustangMainHarness.gif

Ignition switch wiring

http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

O2 sensor wiring harness