My car runs like crap if I let it set for a few days. I plugged my OBD-II reader in it and got codes P0300 and P1614. The P0300 means Random/multiple misfire and P1614 is a NATS malfunction. All this tells me is for some reason the motor is misfiring, besides that I'm lost. Has anyone ever had this combination of codes or does anybody know what would cause this combination of codes? Thanks.

 

There are a lot of people with P0300 in the forced induction world... do you have any engine mods?

Perhaps you need new plugs...? To be honest I've never heard of NATS malfunction

 

No motor mods yet. It may be the plugs. I never thought of that. My dd did something similar, but only from 2500-3000 rpms. This just does it at idle, so I didn't connect the two.

 

Ive never heard of the NATS malfunction myself, but the plugs are supposed to be good up to 100k. They are platinum plugs, and dont require much repairing/replacing.

Im intrigued by this code so I can see what I can find about it.

 

I got to thinking and I don't think it's the plugs. I didn't change them because of that. It will even out a bit after it idles a bit. It smokes pretty bad when it does it too. The exhaust smells a little wierd, so I thought maybe the cats are bad. I also heard maybe the injectors are leaky.

 

I have had a NATS malfunction in my 05Z- It was a connector or voltage variance problem in the BCM (body control module) where the BCM did not recieve the proper signal from the KEY (a NATS function for theft protection) and pass on the accept signal to the ECU (my understanding as to what was going on) and in turn first throw codes and later prevent the car from starting. I had to replace the BCM and get the keys recoded by the dealer.