I had a hotwired factory pump and was running lean at 12 psi, so I installed a walboro fuel pump.

It ran awesome for one drive, but when I stopped, my car was smoking from the speedometer sensor. I got it unplugged and put everything back together which, of course, reset my ECU.

Now it is running lean again. Anything past 9 psi and my AF goes over 12:1.

I have had to replace one engine and I don't want to have to do it again because of this.

Any ideas on why this would be happening?