fuel related miss?

[boostback]

Put an aftermarket fpr on my car. Drove up and down street. Not knowing what i was doing turned the pressure up too high. As i was pulling down the street it leaned out really bad. Parked the car to go run errands came back and it would not start. Put the factory fpr back on checked spark, timing, and compression all good. Finally car started back up now but it has a miss so it sounds like a Subaru. Any ideas?

 

[boostback]

After it leaned out real bad they came back down to 13s. but now with the miss its in the 17s.

 

[BlackKnight2013]

anytime i deal with a misfire i check spark for each cylinder, check each injector to make sure they are firing correctly, check compression and fuel pressure. to take is a step further check your timing and maf sensor. make sure your spark plugs aren't fouled out. ive seen a lot of fouled spark plugs cause misfires

 

[Tyeler18]

What's your fuel pressure, not your air/fuel ratio?

Probably fouled the plugs like stated above, but hard to say for sure.

 

[BlackKnight2013]

another though, even though this is advanced mechanic stuff, with the aftermarket fuel pressure regulator you forced your fuel trims (or adaptive fuel tables) to compensate for the added fuel and when you switched it back over to the stock one the ecu was still thinking you had the aftermarket fuel pressure regulator in and caused it to lean out signifcantly. a way to clear fuel trims is by disconnecting your battery and touching negative to positive cable (drains capaciters safely for keep alive memory)