2002 MK4 2.0 engine. The called stalled when diving on the highway , it was 90 degrees . I had to get towed, it would crank and no start. I checked the car the next morning,with a code reader and got P0321. The car started up right away but the EPC light was on, I ran it for a minute and then turned it off. I checked it the next morning and it started up just fine with no EPC light. I was able to drive it to mechanic's a mile away and it ran fine like nothing happened before.
I bought a sensor , had it installed, picked up the car and drove it to the store and then home. It ran fine.
The next day I took it for a 6 mile ride to the store, it ran fine. When I came back out to leave, it had the same no start and p0321 code. I know they replaced the part because they gave the old part to me. Could it be a defective part or does anyone have an idea of what the problem could be?