D16A1 engine swap, part 2

Before I installed the newly built 1989 D16A1, I made all of the necessary wiring changes. As I mentioned in the previous chapter, the 86-87 D16A1 will drop in with no wiring changes. However, the 88-89 D16A1 required many changes. Some new connectors had to be spliced into the engine wiring harness and some new wiring was added to the ECU connectors.

This is the chart I created after spending many hours studying the wiring diagrams from the CRX and Integra. I used this diagram to figure out what wiring changes needed to be made at the ECU.

Awhile back, I cut the ECU wiring out some junkyard cars. I got an 87 CRX Si harness (just like mine), an 89 Integra harness, and an 87 Integra harness. I highly recommend doing this! Having the 89 Integra harness allowed me to see how my CRX harness should look. I used the 87 Integra harness as a source for additional wiring. The ability to look at the harnesses while sitting down at the desk sure beats being stooped over the car for hours.

Here's a look at the ECU connectors after most of the wiring changes were made. It looks like a rat's nest, but the labels make it pretty straightforward.

Here's a look at 2 new wiring harnesses that I added for wires into the engine bay. The bundle that contains that Crank Position Sensor is shielded. I used rubber grommets in the firewall for a tight fit and to prevent the wires from getting cut by vibration.

Here's the engine bay side showing the new wiring. I used black wire loom and black electrical tape for that factory look. Although the CRX already has wiring for the Purge Cut Solenoid and Idle Air Control Valve, I ran new wires. The CRX has those sensors in the emissions control box that is located by the driver's side shock. The Integra puts those sensors right on the firewall. It was easier just to run new wires instead of trying to extend the old ones.

Now it was time to modify the engine wiring harness. The easy thing to do was to just get an 89 Integra engine wiring harness and borrow connectors from it. The Cylinder Position Sensor (CYL) is located in the distributor on the CRX. The Integra has this sensor in its own housing that is driven off of the exhaust cam, so I spliced in the Integra's connector.

The CRX's alternator connector has only 3 wires. The Integra's has 4, so I cut the CRX's off and used the Integra's.

The Throttle Position Sensor (TPS) connector on the CRX is rectangular. The Integra's is round, so I had to replace the CRX connector.

Here's a look at the engine wiring harness after all of the changes.

This picture shows the location of the CRX's ignition coil. The Integra's coil is located inside the distributor. I needed to extend the coil's power wires over the distributor.

This is the wiring extension that I made for the coil's power. It will be taped and wire-loomed, too. The connector on the end is from the Integra's engine wiring harness. It is the connector that plugs into the distributor to supply power to the coil.

This page shows most of the changes that need to be made. I don't have any pictures of the wiring for the VSS, ELD, and a few other items. However, I will probably add those later.

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