It’s great to open the hood of your car and see nothing but the motor staring back at you. Move up a few generations on any vehicle, though, and you’ve got miles of wiring snaking through every nook and cranny. If your carbureted car doesn’t start, chances are you can pinpoint the source of the problem pretty quickly by checking fuel delivery, spark, and so on. But what happens when you turn the key in a late-model car like our ’88 Firebird and nothing happens? Fergettaboutit. Unlike pre-computer cars, these vehicles rely heavily on what the Electronic Control Module (ECM) tells the engine and the rest of the car to do. Based on information gathered by the ECM from sensors on the engine, the ECM sends signals back to the injectors and ignition to maximize performance in any given driving condition. Unless you have a lot of prior experience in diagnosing TPI cars, it’s not hard to suddenly realize why so many shops charge a high premium for such repairs. However there is an alternative to parts swapping: diagnostic equipment like the Diacom Test Software from Rinda Technologies. Just install the software in your laptop computer and plug it into the Assembly Line Diagnostic Link (ALDL) port with a supplied 12-way connector plug. The Diacom Test Software displays a multitude of engine and performance data and gives you access to any trouble codes stored within the ECM.
Since our Firebird has more than proved that it’s a reliable ride, we really didn’t anticipate any surprise codes to pop out. For starters, it passed smog. More importantly, it hasn’t left us stranded (yet) despite all the nitrous floggings we’ve hit it with, and that we still haven’t done an oil change since we procured the car. The only problem that we have encountered is the radiator puking into the overflow and the electric fans not operating. Of course, we assumed the temperature gauge worked—but we were wrong. Other than that, we’ve cruised worry-free all over L.A. in 90-plus-degree weather and stop and go traffic. Now that we’ve made the car look sexy with its fresh coat of paint, new interior, and killer wheels and seats, it was time to plug into the ALDL port for a check up. So when we plugged in the Diacom software we were pretty surprised to see six trouble codes stored in the ECM. Follow along to see what this computer thing is all about.
