High RPM problem

[MrClean302]

Car runs great until I get to about 4600rpm then it just feels like I've let up on the throttle. It used to rev to 6000 no problem so this just started recently.
It runs smoother now that I've changed my cap and rotor, as they weren't in the greatest shape, but there's still the big drop off in power.
Is it possible that it's a fuel problem? The fuel pump isn't loud or anything but it is the original, I did change the fuel filter two years ago.

Thanks

 

[94MustangGT5.0]

It's either a fuel problem like you said or possibly something electronic. Is your SPOUT connector plugged in? Thats what advances your timing at higher RPM's and without it your car would run worse past 4600. That's just a thought, most likely its fuel delivery. Check your fuel pressure.

 

[MrClean302]

The SPOUT is plugged in.

As for the fuel pressure, how do you check that and what should it be at?

 

[94MustangGT5.0]

Honestly, I have never checked mine, I guess because I have no reason to. Feel free to chime in people who have done this, I believe you can use a standard pressure gauge with a needle indicator. I don't know exactly where to take it from though.

 

[nmcgrawj]

U take the shrader valve out( i think it had a blue cap) and you screw the gauge into it.

What are your mods?

 

[MrClean302]

the engine is stock but I do have a cat back if that makes difference.

 

[WHITE94COBRA]

Check your distributor, mine lost major power in the higher rpm range when it started to go out.