My 2005 Saturn Ion won't start! I've had quite a

Question edited for clarity.
Question moved to model category.

You can't just replace it because it need programming for that car. It have to be programmed with the VIN Number and the mileage. There are very few reasons that you would ever change an ECU. The number is on a paper sticker on the outside.

https://www.google.com/search?q=2005+Saturn+Ion+2.2+ECU+location

https://www.google.com/search?q=auto+electrician+near+me

Speed Sensor

https://www.google.com/search?q=2005+saturn+ion+2.2+speed+sensor+replacement

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Did you replace the bulb in the passenger side running light/turn signal socket? There are two filaments in that bulb, one for the running light (which you indicate works) and one for the turn signal. If that bulb (filament) is burned out, it will make the turn signal flash faster. I don't know why you were swapping headlights, don't know where the fire box under the hood is, and don't know what a jumper sore is, so can't help you any further. I have a Saturn Ion, and have never found a fire box or jumper sore in it.

it sounds like your security system failed..its very common in the gm vehicles. I had this happen to my impala.. check this out I hope it helps.. you are also able to put it in yourself. Hope t helps

your battery maybe weak or the terminals of your battery are loose. check your battery charge and clean and tighten your battery terminals.

First of all your service light came on so give it a service then have the service light reset then check the thermastac, water levels and the choke is working properly and all the elecric working parts are good

have a lock smith cut a new key, the original key might have worn down where it wont hit the points in the keys cylinder. that is the first thing I would try since its the most common problem with the ions.

Insert the key into the ignition and turn it to the "ON" position. There is no need to start the car.

2

Press the button located in the center of the instrument cluster ONCE. The display should now read "OIL LIFE" instead of vehicle mileage.

Read more: How to Reset the oil life monitor on a Saturn Ion ' eHow.com http://www.ehow.com/how_5658600_reset-life-monitor-saturn-ion.html#ixzz28jXOUbyz

the ignition cylinders fall apart and the small plat that holds the tumblers in the cylinder falls out of place you might get lucky and insert a allen wrench into the release hole and pull the cylinder out the hole is about 3/16ths you can get a cylinder coded at a chev or saturn dealer bring your tittle and photo id if you can't remove the cylinder you will need the whole housing

Without doing testing we'd only be guessing ,having a qualified repair shop run diagnostic's on it would be your best bet .
003 Engine Peformance Tests Scan Data Tests
Rigging the vehicle's isn't fixing it . This can cause problems your not aware of. Do yourself a favor an have it fixed correctly

Without knowing if there are more things happening, noises, clicks, whirr sounds, or even how hard you drive it...

It typically sounds like a bad or clogged fuel filter... Although I've had some cars do this in the past, once they were heated up and had to wait an hour ow two to start again... that generally meant the fuel pump needed to be replaced.

This is called a Vapor Lock... and try as you might, they will not start

So, before you start going through quite a few external sensors, idle air control motors and egr valves and etc, etc at 85 dollars a pop...

Considering changing the FUEL filter and pour a bottle of gas drier in your fuel tank. You could have some condensation in your fuel and it may be as simple as that.

However if this dont help or the problem starts happening again, I would replace the fuel pump.

Good Luck and Happy Motoring

Respectfully