Can I Replace my Digijet EFI with GoWesty EFI?

This is a great question and one that we asked quite frequently these days. The short answer is yes, and the long answer is below. Please read on!

Our GW-EFI kit will bolt right onto any 1986-91 Vanagon originally fitted with Digifant Injection. Not so for 1983-85 vehicles that were originally fitted with Bosch Digijet Injection. Many of the items required we offer brand new, but not all the items required are available new from GoWesty or anyone.

Here is a quick breakdown of what is required:

Part Number Description
2.1-COOLING-CONVERSION 1.9 to 2.1 Cooling Conversion Bundle
COOLANT-HOSE-KIT-V2 2.1 Cooling Hose Kit
GW-SS-EXHAUST-INT  2.1 Exhaust Kit
251-198-399M Stainless Steel Coolant Pipes
025-129-627L 2.1 Intake Boot
025-129-620A 2.1 Air Filter
025-906-283C Idle Air Control Valve
025-129-607 2.1 Air Filter Housing (Oval Type)
025-133-055C 2.1 Intake Plenum (Optional but preferred)
025-133-202A 2.1 Intake Runners (Optional but preferred)

Here is a brief explanation of why each of these parts are required:

Cooling system: Three GoWesty kits are required to accomplish this: The 1.9 to 2.1 Conversion Bundle, 2.1 Cooling Hose Kit, and our Stainless Steel Cooling Pipe Kit. The change from 1.9 to 2.1 type cooling system is mostly required due to the new crankshaft position sensing system requirement for our GW-EFI. Specifically, the upper coolant cross-pipe at the pulley end of the engine is present only on the 1.9 type cooling system, and is right in the way of where this system is installed. Even if you are not installing our GW-EFI, switching over to the later 1986-91 type cooling system is a no-brainer. It is vastly better in all regards and all Vanagons should be upgraded, full stop. In the final analysis, it was decided the best course of action is to simply require the later cooling system as a requirement to run GW-EFI.

Exhaust system: The location of the oxygen sensor on the 1.9 type exhaust system interferes with a part of the 2.1 type cooling system, which is a required upgrade for our GW-EFI. The alternative to replacing the entire 1.9 exhaust system is simply to move the oxygen sensor to the catalytic converter, where it is located on the 2.1 exhaust system.

Air filter housing: The shape of the housing is totally different but fits all years without any modification to the vehicle. The shape is not the important part. The important part is the size and position of the original air flow meter that our MAF housing replaces. These filter housings are not available new. You will need to rustle up a used one.

Idle air control (IAC) valve: These are available new, but we have not found any new ones that work exactly like the originals, which is what your EFI system is designed to work with. The good news is that the original IAC valves rarely go bad, so good used examples are easy to find.

Intake runners and plenum: The 1.9 intake runners (manifolds) are slightly smaller than the 2.1 type. The plenum has slightly smaller fittings to match the slightly smaller intake runners. These differences are not important, at all—but if one is changed from 1.9 to 2.1, so should the other. The problem lies with the 1.9 plenum. It has a different shape fitting and a mounting bracket for the 2.1 IAC valve. It is not terribly difficult to plumb-in and mount the IAC Valve on a 1.9 plenum, like this for example: