The Haltech Journey
So the big question here is why? Why did I go from Chrome Ecu to Haltech? Well to start it was actually Chrome Ecu to AEM Series 2, then to Haltech.
The journey started like most, when things started to fail. I had been fighting 30 year old decaying wiring issues and a slowly dying instrument cluster. So what does that have to do with swapping the ECU. It basically comes down to removing the 30 year old tech for more modern stuff and rebuilding a new engine wiring harness. This is the main point for a lot of the work I do on the car. Why replace an aging part with an aging part that costs more when I can install a performance part that’s usually cheaper. With the gauge cluster I had the option of building a new one using separate individual gauges, trying to cram them all into the area the stock cluster was, or trying to update to a new modern video display type screen. The display screen was my choice but that meant needing to update the ECU also to work with the screen. At this point it was all ideas, until a sale came up for a series 2 that made it reality it had all the sensors needed to get things up and running.
With the new AEM Ecu I went ahead and ordered a CD7 Digital display to replace the stock cluster and began work on the new harness. With this harness I wanted it to have a main bulkhead connector that would allow me to disconnect the engine harness without needing to pull the entire harness out. So I picked up a 47 pin Deutsch bulkhead connector. For the engine side I made each run its own separate run. I didn’t want all the wires being wrapped into some giant umbilical bundle that still makes it a pain in the ass to troubleshoot wires. So each sensor/connector had its own run with all the wires contained.
For the most part I was able to reuse the stock wires, but cut back any portion of wire that was damaged/decayed. This allowed me to stay with the stock wiring colors. All new connectors were installed for every single thing on the engine. All of the wire runs were wrapped in High Heat Tessa tape and then covered in wire braid for a nice clean look.
Tuning on the AEM was handled by RacerX Performance and in no time the car was up and running and I was driving it around. We had a few issues here and there but for the most part everything was working great, except for the speedometer. We couldn’t get a working signal for the speedo on either of the inputs for the AEM. We confirmed the speedo sensor was working but the data coming into the AEM was bad.
I reached out to AEM for support and after some back and forth troubleshooting we concluded that the inputs were bad on the AEM and it needed to be repaired. I asked them to start the RMA process so I could get it sent in for repair. This is where it all went downhill…. AEM Support tells me they are no longer doing repairs on ECU’s and they have just shut down their entire ECU line. They did refer me to a third party company that is now handling their ECU repairs. This was the point that I knew AEM was no longer a viable solution. Knowing they shut down their ECU line, they were “end of life” and not something that was going to be heavily supported as I wanted in the future. This was the point I knew I had to make the switch to Haltech.
I sat down to plan things out on how I wanted to make the conversion over to Haltech and what all I was going to need. After many discussions with Chris over at R’venge Performance, Jeremy at Remy’s Rides and Morgan with RacerX Performance I came up with a game plan. The build of this goes along heavily with removing as much of the 30 year old tech as possible and replacing it with more modern equivalents. There was some trial and error to all this as I worked through things but in the end the Haltech swap over ended up with the following parts being installed.
- Haltech Elite 2500 ecu – This unit will include all of the functionality and I/O needed to make the full swap
- Haltech Harness – Buying the harness instead of converting my original one over came with a lot of benefits. Not only are the ecu plugs already pinned, the wires are all pre-colored with enough ground/power leads for all of the I/O, it also will allow the removal of the stock MFI relay and a bunch of other stock wiring that is no longer needed. The Harness comes with its own power distribution block that is pre-wired with relays for the higher power draw functions.
- Haltech Can Bus Dual Channel Widebands – This will replace the stock narrowband O2’s with full Widebands. Since this connects right into the Haltech CAN BUS it is fast and responsive and doesn;t use up any Haltech input channels on the ECU.
- Haltech Sensors – The map and pressure sensors “Fuel & Oil” are all Haltech. I originally tried to use the AEM sensors but had some issues with them so I swapped out to Haltech ones. The stock coolant sensor is still retained and a GM IAT sensor is also used which is the common IAT sensor most used.
- Haltech CAN BUS Hub – Allows all of the CAN BUS stuff to plug in using the 4 pin mini Deutsch connectors. Granted you can just splice all these wires together, I just find this a cleaner way and more easily serviceable.
- Haltech IC7 Dash – This will replace the entire dash cluster assembly. It is paired with a Mako Motorsports surround to make it look stock in the dash opening. The surround is a bit on the pricey side but the overall quality and clean fitment makes it well worth the price.
- Rvenge Performance COP Kit – Again with removing old tech, moving over to a full coil on plug kit means I delete the spark plug cables, the coil pack and the PTU. If you had to replace those three items the cost is about double what the COP kit itself costs.
- Rvenge Performance DBW Kit – I was a bit hesitant about going DBW and it took some time to weigh Pros vs Cons. In the end the added functionality of being able to have Cruise Control back without adding anything additional was probably the sway point for me. This would also be considered removing old tech as this deletes the stock throttle body, IAC, FAIV, throttle cable, and stock pedal. For those with a more stockish car it also removes the massive cruise control assembly.
One main thing that people need to know is that moving over to Haltech is NOT a plug and play application. At the time of writing this there is no conversion harness that I know of to convert the stock ECU plug to the Haltech ECU. Even if there was, I would not recommend going that route. These cars are too old now to be reusing the stock engine harness and plugs. The stock wiring did not hold up well over the years to the engine bay heat, especially where the wire leaves the looms and goes into the plugs. I think every plug used in the engine is unsealed, meaning the wires are exposed before entering into the plug itself. This is where the wire coating has broken down, the wires have oxidized and corroded away. The aging wires in the engine bay are a common cause of engine problems in these cars today. There are still some stock plugs that have to be reused, mainly the crank/cam sensor and engine temp. Everything else in the engine bay should be getting replaced with a different sensor or has different plugs/pigtails in which I used Deutsch connectors for.
For the install I will be breaking it up into multiple sections as there is a lot to cover. These will be specific to my install and not a guide on how to install it. Since my car is completely custom and nowhere close to being stock, how I do my install will be different from how someone with a stockish car would do their install. A lot of the information will transition over but not every step will.