3.9 ford 2005 backfire

ford
freestar

#1

At 2000rpms the motor backfires. It has new plug and wires and map sensor. 203000 miles


#2

Backfiring usually means it is getting gas or too much gas at a place or time when it shouldn’t be getting any or that much gas. Often times this is related to a timing issue. I’d start with a good look at the ignition system, wires, dist, etc. Check the timing. Could something be leaking? Is the advance working (if it has one, it’s probably electronic.)


#3

I’m curious, what year/s did Ford make a 3.9 engine?? It saeems to me that the original V6 was 3.9.
No, the original one was 2.9 sorry.