cant download computer

Before I totally make myself look like an ass, let me tell you I know next to nothing about cars....especially car wiring. So, let me get to my problem. My check engine light came on about 3-4 days ago. I took it to get a diagnostic, and they told me it wouldn't download. Now, if I was in the US, I would probably be able to get it fixed no problem, however I am in the military overseas in Italy. The people here have no access to wiring diagrams for US model vehicles. Does anyone know where I might be able to get a good diagram for the computer wiring? I am a little concerned that when I had someone install a new CD player, they may have screwed up or cut the wire from the computer to the diagnostic hookup. I have no idea what I'm looking for though....any help?

May be able to help. What year, and what engine/tranny. I wont be back online until Wednesday. I'll be sure to check back then.

2000
2.2 L / 4-cylinder
Automatic

Thanks!

maybe you can help me with the real problem on the car as well. The check engine light is flashing on and off, and when the car is in idle (and all the way hrough first gear), the car shudders horribly. I thought maybe it was something with the fuel pickup or the injectors, so I ran a fuel treatment through, as well as changed the fuel filter and spark plugs. Nothing helped. Now I'm thinking it's maybe in the exhaust system. I need help!!! It's next to impossible to find a good mechanic here that knows how to work on GM cars.

A flashing SES light is usually a loose electrical connection. Check the battery connections and the engine ground cable. The hardest acceleration is in first gear and so the timing advance is greatest then. If you find no loose or corroded connections then check you EGR system. You may be getting too much or not enough recirculation. Tis can be tested by unpluging the EGR and driving the vehicle. The PCU will see the missing EGR and run the engine in a "Limp Mode". If the engine runs smoothly then you have found it. You will notice a slight reduction in power and you will set a code in the computer. The SLS light will stay lit after this test until you clear the code. You can order a nice handheld scanner for all late model cars sold in the US for about $150.00. I use an Actron brand unit that can be purchased online from most larger auto parts stores. With it you can download your own computer, clear codes as needed, even scan systems for proper function. Good Luck.

OK, Thank you for your detailed post, but as I stated before I am a dummy when it comes to cars..lol. What is the EGR?

It is a valve that lets some of the exhaust go back into the intake to be re burned. This improves emissions. I is on or near the top of the engine about the size of a soda can. held on with 2 bolts and has a electrical plug on the top/end. You can go to the Autozone.com website put in your vehicle info and they usually have a photo of the item. It will be under emission componients. You will be asked to enter a zip code, use the one from home or use mine 32738. This is required because the site will show inventory in you "local" store. I do believe the online store will ship to an APO address. If not partsamerica.com or some one will.

As far as I know the 2000+ cavalier does not have an egr valve