Q: Car was running rough, so I figured out it was a faulty ICM. Changed that, now car won't even start.

asked by on January 30, 2017

MY BUICK WAS RUNNING VERY ROUGH. I did some simple checks, and found that one of the coils wasn't working. I changed the coil, and it still wasn't working, so I removed the ICM and took it to auto zone to have it checked to see if that was the problem, it was, so I changed that. I installed the new icm, and went to start the car, and now it turns over, and acts like its trying to run, but won't run. I checked to see if there was spark, yes there was. Checked the fuel valve, there is fuel. What could be causing the car to not run all if the sudden, when it was running before, although it was running on 4 cylinders, it was at least running
My car has an automatic transmission.

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Hello, thank you for writing in. With the new module you installed, there is likely some other issue with an input to the computer. Either that or the computer itself is having issues. You can only test the computer by testing its inputs vs. its out puts. If it looses connection over the computer, you know its the component to blame. You will also want to check all of the wiring and make sure the terminals are all clean, dry, and tight. If the entire ICM system and computer checks out, then you want to turn your attention to the intake air sensors, and having the vehicle re-scanned for codes if possible. The last recommendation is to verify the repair of the new module that was installed in the first place. Make sure it is the right module, and is communicating effectively. For more diagnostic help, contact our service department to schedule an appointment.

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