GoWesty Fuel Injection Component Replacement Kit (GW-EFI)

Works With:1983-1991

Requires professional-level tools, talent and experience.

1 Review

Proposition 65: This product may contain chemicals known to the state of California to cause cancer, birth defects, or other reproductive harm.
Self-certified made in USA of U.S. and imported parts

For many years now, the "Achilles' heel" of the 1983-91 Vanagon has been the antiquated and usually-problematic Bosch engine management system. Even when it was brand new, it was far from perfect. Fast forward over thirty years, and one finds as that every wire, connection, and component has the potential to bring your perfectly planned road trip to a screeching halt. Volkswagen themselves knew the system had genuine flaws, as did every Vanagon owner, repair shop, and parts retailer.

For over a decade, we explored fixes, patches, upgrades, and improvements. We were convinced we could get it to work reliably, but we were wrong. Short of Volkswagen releasing brand-new parts to completely replace the entire system, the original Bosch management system was going the way of the Dodo.

The writing was on the wall: The system had to be replaced with something smarter and more reliable.

But what would this be, and who would invent such a thing? Who else? GoWesty! We rolled up our sleeves back around 2012 and got to work! After thousands of test hours, tens of thousands of test miles, and an unbelievable amount of effort, we were finally able to release this system in January 2018! Read the full story.

This product does the following:

  • Replaces no-longer-available-new (NLA) Bosch components
  • Improves reliability
  • Improves fuel efficiency
  • Improves performance
  • Adds self-diagnostic capability (OBD-II)
  • Compatible with any 1986-91 waterboxer currently running Digifant fuel injection!
  • Smog-legal in all 50 states! Executive Order #D-786-2
Do you have a 1983-85 Vanagon with Digijet Injection? Read this article

The GoWesty Engine Management System is comprised of:

New Electronic Control Unit (ECU)

  • Replaces no-longer-available (NLA) Bosch ECU and Idle Control Unit (ICU)
  • Has standard OBD diagnostics via OBD-II Added feature
  • Compatible with standard real-time parameter displays, including ScanGauge—Added feature
  • Capable of future software updates if/as needed—Added feature
  • Sequential-fire injection instead of batch-fire injection

All-new Billet Aluminum Throttle Body with modern TPS

  • Replaces worn-out original throttle body with a new redesigned unit
  • Modern, sealed TPS replaces antiquated and NLA factory throttle position switch
  • Obtains accurate throttle position throughout the throttle range

Modern manifold absolute pressure (MAP) sensor

  • Added sensor for better fuel management control
  • Used to obtain engine load and barometric pressure reading
  • Provides data for automatic altitude compensation—added feature

New oxygen sensor

  • Replaces antiquated factory oxygen sensor
  • Modern 4-wire design with sealed electrical plug—added feature
  • Used to adjust fuel trims

New knock sensor and controller

  • Added sensor to protect engine against detonation/pre-ignition
  • Used to detect detonation/pre-ignition (called knock) and retard timing to mitigate detonation/ pre-ignition

Modern distributor-less ignition system

  • New electronic coil-on-plug ignition coils replaces antiquated factory single coil
  • No more high-voltage ignition wires - a common source of spark that causes engine compartment fires - new feature
  • GoWesty-designed cam position unit and crank position wheel replaces antiquated distributor, cap, rotor, wires
  • Used to accurately determine crankshaft and camshaft position

Modern Mass Air Flow (MAF) sensor in GoWesty-designed MAF housing

  • Replaces antiquated and NLA factory "trap door" air flow meter
  • Measures mass of incoming air in order used to calculate required amount of fuel injection

GoWesty Tachometer Adapter

  • Converts the digital tachometer signal from the more modern ECU to a signal that the factory tachometer will read

GoWesty Fuel Injector Bundle

  • Modern, brand-new, flow-matched injector set designed specifically for our EFI.

ScanGauge OBD-II Kit & Dash Mount

  • The ScanGauge adds an OBD-II dash display to your GoWesty EFI System. This is a must-have tool for monitoring the health of your engine in real time, and is indispensable when it comes to diagnosing issues. 

GoWesty-designed all-new engine management wiring harness

  • Replaces prone-to-moisture intrusion, antiquated, corroded, and NLA factory harness
  • All modern, completely sealed connectors for years of trouble-free service in all conditions
  • Also included with every kit is a GoWesty ALT-HARNESS to ensure a reliable power supply to the system!


Ignition timing: Timing is set to original factory specifications. 35 degrees at 3000 RPM. Idle speed and fuel mixture is not adjustable and is completely automatic, as it was (supposed to be!) with Digifant.

Existing Components: Several components of the original fuel injection and delivery systems are not replaced by this kit, and their proper operation is critical for the new GW-EFI system to work properly and reliably. It is HIGHLY recommended that all of these listed below be replaced if they are original, or of unknown age. GoWesty will continue to supply these items individually for the long-term, of course.

Download the installation instructions on the "Instructions" tab to see the pre-check procedure.

  • This system's components (except ECU) are warranted against defects for 12 months/12,000 miles (whichever comes first).
  • The ECU is warranted against defects for 10 years, unlimited mileage.
  • Professional installation is highly recommended.
  • Technical support for issues at start-up will be offered free of charge, but only between GoWesty support staff and a professional technician.
  • Technical support is otherwise offered at $75/hour, See item GW-TECH-SUPPORT.

EMISSIONS INFORMATION: Gowesty Fuel Injection Component Replacement Kit (GW-EFI) has received an official California Air Resources Board (CARB) Executive Order #D-786-2, and is smog-legal in all 50 states.


GoWesty Fuel Injection Component Replacement Kit - Installation PDF

GW-EFI Mechanic's Guide 

GW-EFI Handbook

GW-EFI Wiring Diagram


Estimated Installation Times:

      • Professional VW mechanic first time GW-EFI install : Estimated 10-12 hours
      • Professional VW mechanic, who has previously installed the GW-EFI: Estimated 8 hours
      • Amateur: Estimated 14+ hours

Need replacement parts, like an oxygen sensor or an ignition coil? Fear not, we based our system around readily available parts that you can source from virtually any auto parts store, or pop some in your cart from the list below.

Prefer to hit up your local parts supplier? Download the Local Auto Parts List PDF

GoWesty Fuel Injection Component Replacement Kit (GW-EFI) Wrench Rating

Pro — Requires professional-level tools, talent and experience.

All Wrench Ratings

Plug 'n' Play — Requires no or basic hand tools and no mechanical knowledge.

Handy — Requires some hand & power tools and minimal mechanical knowledge.

DIY — Requires a full tool set and broad mechanical knowledge.

Pro — Requires professional-level tools, talent and experience.

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