ok, so the car was running fine except the alternator died so I ordered an FD alternator and put it on my car. So it seems to be working fine except the first night with the new alternator it snapped the belt...so no biggie we put on a new one but now the car overheats and seems like it isn't really pumping coolant through the engine or anything beceause it just goes into the overflow tank and pours out everywhere

next, the car won't idle anymore...if you sit there for about 10 minutes nursing it, it will idle but not if you go driving...it just dies everytime you slow down.

And finally as soon as you hit 3800 it just hits a wall and backfires like crazy. You can push it past that point but it just like stops there for 2 whole seconds before moving on and it's not like the 3800 rpm hesitation I had before, it is crazy. And the car is continualy backfiring all the time everytime your rpms drop.

I tried searching and it seems like it is more than just grounding the ecu, but that might help too. The car has 2500km's on the rebuild.

 

Have talked to the shop that did the rebuild?

To check the primary grounds:
Engine running, headlights on, the voltage from battery (-) to the alternator frame should be zero.