Hey guys, I have a issue with my d16y8 M/T, every time I would give the car more gas the car has this pow! sound on all four cylinders around 5k rpm and it reduces horsepower. I done a compression test and cylinder leak down test and they all pass (higher spec rating). I checked to see if I was getting enough air into the engine and same with fuel and spark and it was. I have 2 inch headers to 2.5inch piping all the way and a open cold air filter (k&n). I think I could have a bad EGR valve but I want to see if anyone else had or is having this issue too, please help! Thanks!

 

If your check engine light is on, check your malfunction indication codes & resolve them.

http://phearable.net/information/check-codes.html

 

When was the last time you did any general maintenance - Spark plugs, plug wires, cap & rotor, fuel filter etc?

 

There's no check engine light on and no codes. I changed the fuel filter a few months ago, but plugs, wires and anything to do with the distributor haven't replaced it. I used a ohm meter to see if there's power going into the plugs and there is. Also thanks for the replys!