Couple months ago, I bought a 2000 Mustang convertible 3.8L, manual tranny, overall in a very good shape, only 67000 kms on the clock. No issues/problems then.
Few weeks ago I put two mods on the car. First a high flow muffler, which did not create any problems. Later on, I installed a K&N air filter and that was when problems started.

I need to tell that both mods had actually a positive effect on performance, more power and better torque especially at low RPMs. However, shortly after installing the K&N filter, I noticed that when accelerating in lower gears, the engine starts missing/skipping past 2500 or 3000 RPM. It feels like the fuel was momentarily cut off. No problems when cruising or in 5th gear.

I did search the net and as recommended, I cleaned the MAF sensor. It seemed to help a bit but this skipping is still clearly there. I wonder if by letting the engine breathe more freely the fuel management system is somehow confused about fuel delivery.

Any help/comments would be appreciated.

Lumir

 

When I read the title of this thread I was like, "How could someone lose an entire engine"? LOL! Sorry, just kidding. I put a KN filter on my '07 and so far have great luck with it.

 

Have you pulled and checked the plugs?

2000 has a problem with the baffles in the valve covers that lets oil get sucked into the PCV valve. Causes carbon build up in the engine - translates to misses. Pull the plugs and check them. It's possible the increased flow from the air filter is causing more suction through the PCV.

The fix is to either replace with updated valve covers or install a filter in the PCV line.