Knock knock......

[Grand natty garage]

I been chasing knock at higher rpms for a while now. Think I finally figured it out, fuel pump is original and I noticed the pressure drops after reving out. O2 milivolts seem to be normal but I haven't watched them when it's reed out. I'm about to install my a/f gauge to see what that's reading. Blm 128 and alky kicks on amd ramps when it's supposed to. I ordered a new deatchwerks 255lph pump. Once that's installed, I'll post an update if any one is interested. I'm not gonna do any more pulls until that new pump is in, don't wanna open a can of worms..

 

[TexasT]

You are playing with fire on that original fuel pump. New pump and a hot wire at the minimum or you will be going deeper into the engine sooner then later.

 

[Grand natty garage]

You are playing with fire on that original fuel pump. New pump and a hot wire at the minimum or you will be going deeper into the engine sooner then later.

You are playing with fire on that original fuel pump. New pump and a hot wire at the minimum or you will be going deeper into the engine sooner then later.

Absolutely, I agree! Honestly it should have been the very first thing I did when I got the car years ago. I've had the hotwire for a wile but never touched the pump. New one gets delivered Monday

 

[Chuck Leeper]

fuel pump is original

What Rich said, and....
Filter too?
Injs clean?
When the tank is down, change the tank to frame hoses.
Verify voltage and ground at the tank hanger connection.
Volt drop tests are always a good idea with this type of issue.

 

[dynoman]

First , list all your mods to the car in your signature so we don't have to ask " do you have this or that " . I'll assume you have a Scanmaster ...correct ? If you don't have a Powerlogger , get one . It will help narrow down any issues . Also are you checking alky pump pressure ? Just because it's turning on doesn't mean it's pumping with any pressure and this is overlooked on many Alky injected cars .