I'm awake and pissed off, not a good combo if you have my attention.

[dadagoboi]

Check the battery cable to battery terminal connections.  Looseness or corrosion, especially at the negative connection can cause the symptoms you're having.

The dealer should have disconnected the battery ground before they did any ignition work.  While doing that they would have seen there was an iffy connection and realized that was the problem.

Obviously they didn't follow procedure and installed parts that weren't needed.  They owe you money for unnecessary work.  They are both lazy AND stupid.

Spend a little time and clean up the battery terminals.  You can buy a tool but fine sandpaper works fine.

[the mojo hobo]

It is possible that the mechanic did disconnect the battery ground before working on it, and when replacing it got distracted and forgot to tighten it up.

I have found wrenches under the hood of my car. Once after an oil change I noticed a little leak under the car and found a loose drain plug with the wrench socket still on it.

[Pilgrim]

At one point in my life I was a pretty good shade tree mechanic. I worked on my cars when I was a teen. At the old house I had two Farmall H tractors to twist a wrench on. It's rare these days that I look under the hood. Nice to know i haven't lost my touch  

Hey, when YOU find the problem, and it's that simple, you are 1000% entitled to be pissed that they missed it.  I do understand that such things can be missed - and I've done it myself - but that's what you pay them NOT to miss.

[dadagoboi]

Hey, when YOU find the problem, and it's that simple, you are 1000% entitled to be pissed that they missed it.  I do understand that such things can be missed - and I've done it myself - but that's what you pay them NOT to miss.

For sure...I took my van to a shop to have a leaking heater hose installed because I knew I didn't want to spend the time to remove all the necessary items it had to thread through.

Got it back and found they had CUT the new $125.00 hose and clamped it back together to make the job easier for themselves.  There was a time I would have done the same thing myself but I wasn't about to pay someone to do it.  I cancelled my check and told  the shop owner to take me to court when he wanted to know why I hadn't called him before doing that.  He let it drop.