well not the car but the engine was i hydrolocked it, and they replaced it with a new one for 10k (insurance)

 

but what if they are correct about the bad air filters?

 

I think everyone should get the ECM software updated and make a note of the change in the sw p/n. Since having it done months ago, I have not experienced any more rpm surges, the idle rpm stays lower, and the heavy knock has not returned. Toyota and Nissan may be sharing the same software?

 

you will experience things that are even worse....

 

Sounds like someone may have left a coil loose or slightly unplugged. Not unlikely since it's not the original engine, and most of the parts (coils included) would have been swapped over to the new engine. This would cause a misfire, and misfire codes don't leave the CEL on, but are stored in the ECM. They probably realized their mistake (I'm asuming they replaced your engine?) and fixed it and made up some bogus story about a MAF or something.
P.S- The OEM air filters are actually better than most aftermarket ones...

 

well its been running fine for for a week now said they just replaced the air filters....

your prob correct about them forgetting something when they replace engine, but who knows why it took 8 months to show up
either way im happy now...for now