Engine/Transmission (1998.5 - 2002) Fuel Connection Questions

[TJMIV]

Going to install my fuel pressure gauge along with a couple of others. My gauge has an isolator, & I have been reading something about mounting this isolator in a certain location or position. Can someone relay some more info on where & why, also have the schader connector hose from Geno`s Garage ,do Ineed to hook it up at fitting before filter housing, or at vp44 fitting. P. S. changing filter about every 15,000 miles. T. I. A. TJMIV

 

[JFinke]

A lot of people don't use the isolator, and get a needle valve. It will make it a slow leak if one does develop, and you can turn it off if it does. Just make sure if you use a valve that it's barely open. This will also dampen the fluctuations in the Gauge. As far as where to mount the isolator, I put mine on the brake booster hose with a couple of zip ties. The shrader valve on the pump will tell you post filter pressure, and the one on the filter is pre filter pressure. You want to know what the post filter pressure is. Before you hook everything up check the pre filter pressure and then you will know what the condition of the filter is. I change mine at 10,000 miles and normally gain less than 1 PSI at WOT but nothing at Idle. If you start to loose at idle you know the filter is plugged. My gauge set came with new larger size banjo bolts, and one was tapped for the 1/8" compression fitting. Jake

 

[Gregg Mig]

JFinke, where did you get the needle valve,and what size one do you recommend? Gregg.

 

[JFinke]

I am still using the isolator. You should be able to get a needle valve at any NAPA store or hydraulic shop. When I need to change mine I will go with one that is 1/8" pipe to match the banjo bolt hole. Where you are using the schrader valve setup, just get whatever size it is for an easy match to the end of the hose. Jake

 

[TJMIV]

Thanks JFinke for the info. I guess it is more important to know how much pressure is at the vp44. As for the isolator, does it have to be mounted so that the fluid inside is pointing up or does it matter? T. I. A. for any insight to this matter TJMIV

 

[JFinke]

Mine is mounted horizontal, because it was an easy place to mount it on the brake booster hose from the power steering pump. You can mount it any direction you want to though, because even if there is a little air in it, it will compress and be the same pressure as the fuel on either side. The only thing to be carefull of is that you dont let the guage side of the isolator loose any fluid. If it looses too much it will show no pressure even if you have pressure at the VP44. Jake