MPI questions.....

[will_m]

I asked the same thing on JU and got really no where so here is my post. Tell me your opinions:

O.k. got a YJ with an MPI kit. I think the fuel pump is going. The Jeep seems to ping and rattle a lot if I want to jump on the gas. The cat was changed less than 1,000 miles ago.

Now, I checked Hesco's site ( www.hesco.us ) and they have 2 of them. One regular replacement and one that provides higher pressure (70-90 psi.) The difference in price is $10.

Now here are my questions:

1) What is the normal pressure of and fuel pump for a 4.0L fuel pump?

2) Will using a higher pressure pump do anything bad? (This is an older engine with 130,000 + miles.)

And, on a different note:

3) What should the order of fuel delivery be?
a) fuel tank - pump - filter - engine
b) fuel tank - filter - pump - engine

Thanks for any help.