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Q: ECU related

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Hi this is a funny story actually. My Saab had trouble starting. Everything electrical would turn on but the car wouldn't start. There would be some clicking so we went ahead and changed the starter. We still had the problem. One day I hit the top of the electrical control unit out of frustration and it magically turned on. So now every time the car wont start I hit the same spot with my hand and it turns right on. I'm thinking there is a short possibly but hitting it works. Please help!

My car has 93000 miles.
My car has an automatic transmission.

A: Hi, thanks for writing in. By the informati...

Hi, thanks for writing in. By the information you’ve provided, it sounds like there may be a connection inside the ECU that has broken. When a soldered connection breaks due to vibration, or an impact, sometimes there will be a hairline crack in the solder. There will be just enough of a gap in the solder that it won’t make contact, and when you hit the top, it can close up the gap and make just enough contact to allow normal function for the moment. If this is the case, it will get worse over time and quit working all together. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make or suggest any repairs as needed.

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