Okay, seen some similar problems on here. This lumina gets hot, then dies, won't restart for at least 15 minutes. Check engine light comes on, and it cranks, but no start. There's no codes on here, it just flashes 12 over and over. I took it to a guy and he "thinks" its fuel injectors. However, I cannot pay him upwards of 600-800 dollars to MAYBE fix my 1000 dollar car, right? Also, it has a bit of a hesitation when driving cold, especially when you brake, or come to a stop, it ALMOST dies. So, first question, if the injectors are bad, why does it run cold just fine? Second question, would a really good fuel injector cleaner help out? And third question, how much of a pain is it to change the injectors? If someone could give me an idea of what's involved, I may just buy them and swap them out. Any help would be great, thanks.

Also, the guy I took it to said that two injectors were easy to get to so he tested them. One failed when the car was hot, but passed when the car was cold. But another guy I really trust I called in another state says that an OHM test on an injector is BS........any thoughts??

 

If I was troubleshooting this from scratch, when the vehicle died, I would have a helper crank it, while I checked for spark at the plugs, If I have plenty of spark, then go to the fuel system. I'd check fuel pressure, change the fuel filter if it hasn't been changed in a while, make sure there is no pressure on the system before taking any connections loose. Eventually, I would get to the fuel injectors. You have to do testing when the vehicle refuses to start.

The vehicle requires a richer fuel mixture when it is cold, once it warms-up, the mixture has to lean a little. If the mixture is too rich on a warm engine, it will run poorly or not at all.

I can't say for sure, what your problem is, but, if there was a problem with an injector, no fuel in that cylinder, the extra oxygen in the exhaust may cause the o2 sensor to showlean, the computermay react by adding gas to the other cylinders, that may not work well on a hot engine.

Can you hook a scanner to it, so you can see engine data?

I just wanted to add if theCTS is showing cold on a hot engine, that will kill it. I'm not saying that is the problem, you would need to do some testing.