Flat spot when Accelerating?

[rustorbust]

I cant figure out what is up with the motor. I have a 1976 280z that has an original l28 engine. It has the original fuel injection. When i have the throttle wide open it looses power after about 3700 RPM's, it doesnt loose all power but there is a very noticable amount. It hasnt done this forever but hase been getting worse recently. I have the timing set right so i don think that is the problem. I was wondering if maybe it could be the fuel pressure. Has anyone had problems similar to this. Little help please.

James B.

[ryoojin83]

for starters, I would Read the Sticky notes in this forum...

this isn't an article so this post will probably be deleted...(from this forum) next time I would put it in the help me section or the fuel injection section.

but ill try and help anyway.

I'm really not sure what your problem is, but I've heard of people having similar problems when running SUs, they just don't have enough fuel flow, pressure is fine at low engine speeds but at higher speeds the fuel pump just can't supply the needed volume of gas. your hard lines could be clogged.... maybe put a fule line cleaner in? just a guess... I'm sure there are more qualified people to answer this here, but no one has yet so I thought i'd give it a try...

[St.stephen]

sounds to me like you are perhaps losing fuel pressure or its ignition related.

some questions to answer......have you checked the plugs? perhaps they are fouling.

Cap?

rotor?

Fuel Filter?

Fuel pressure regulator?

Rust in tank?

intake boots before and after AFM?

vaccum leaks?

air filter?

Theres a small list to start if you haven;t checked any of those things as of yet. If you have checked those things, let us know the condition to help better troubleshoot.