Fuel Pump Replacement

WIP95MRK8

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Ok so I finally came up with the money to do a couple of upgrades on the Mark by telling the wife I was going to buy a Honda to save on gas. Now I just ordered my SCT tuner from Lonnie and a 180 degree t-stat as well as a 255 LPH fuel pump. After reading posts after post on this process and all the links in them being not found I want to be sure I am on the right page.

Fuel Pump replacement starts buy running the tank to almost nothing. Putting the car on ramps. Loosening the tank straps and the fill hose and dropping the tank. After which it should be fairly easy to disassemble the pump and replace? I'm sure I missed something so any help and pics would be appreciated.

Thanks
 
Tank is a little more involved than that. There are a half dozen small hoses and tubes to be disconnected in the process. You have the jist, though. The exhaust has to come down as well, which is the most difficult part on an older car. Involved a sawzall on mine.

Why are you upgrading the fuel pump? There's no need for a bigger pump unless you have a power adder of some sort, or some pretty serious head work. It won't gain you anything unless you're already using more fuel than the existing pump can supply. Of course, if the old pump is toast anyway, doesn't hurt to upgrade when replacing, but I still wouldn't bother with more than stock unless the price was lower or I planned on a supercharger or built engine.
 
Well I am having Lonnie put together a program for me including the new fuel pump which Lonnie highly recommends when doing the new program. I am also upgrading to a 180 degree t-stat.

So now what, I already got the pump and the program is being made. Any other thoughts?
 
Be prepared to replace your your fuel pressure regulator as it is not uncommon for the factory units to start leaking, especially with the larger volume pumps. You may be OK, but just advising you to keep an eye out for leaks at the FPR.
 
I don't understand - the fuel pump should not matter to the tune. This is a return setup - the fuel pressure is controlled by the fuel pressure regulator and the fuel flow is relatively constant - not controlled by the EEC. As long as your fuel pump can supply what the engine is making at the pressure required, the size of the pump is irrelevant to the tune. Note that this is probably not the case with newer cars running returnless setups.

But if you're upgrading anyway might as well go big or stay home.
 
I don't understand - the fuel pump should not matter to the tune. This is a return setup - the fuel pressure is controlled by the fuel pressure regulator and the fuel flow is relatively constant - not controlled by the EEC. As long as your fuel pump can supply what the engine is making at the pressure required, the size of the pump is irrelevant to the tune. Note that this is probably not the case with newer cars running returnless setups.

But if you're upgrading anyway might as well go big or stay home.

Well I had read some of Lonnie's post that it was highly recommended and also on BOC's website their spec sheet asked what size I had so I figured why not. So might as well "GO BIG" .
 
So I am all done with the pump replacement. This was definetly a "PITA" and also uploaded the new program from BOC and I love it. I am thinking back to the install when I changed the wires for the new pump and used butt connectors to put the wires together. I am a little parinoid about that. Should I have put anything over them or am I good to go. Thoughts please...
 
Not sure that's what I'm looking for but if I am sure my crimps are good will it be okay? I'm not worried that they will come apart just that if fuel gets up there will it be okay. I drove it today but only had 3 gallons of gas in there.
 
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