Engine/Transmission (1998.5 - 2002) air trapped at fuel press sensor

[lrox]

I hope someone help me with this. I have air trapped at my fuel press sensor. I replaced the banjo bolts with the high flow from Geno's, then installed tapped bolt at fuel pump, then installed snubber to eliminate any pulsing, then installed the sensor. Do I also need to add a extension with a grease gun hose. My gauge still is bouncing, and if I bleed the line at the sensor it will clear up for a couple of days. Do I need to install FASS system. Has anyone else had this problem?

 

[Rman]

is your sensor mounted on the VP44... ? It sounds like it is, this is very bad, the vibrations of the engine will surely kill the sensor in short time. My vote has always been, and always will be for mechanical gauges, but if I HAD to put a sender I'd be sure and rubber mount that thing far away from anything resembling vibration. A new sender and a proper mounting place would be the best fix. I'd keep extra senders around, you'll need them.

 

[Todd T]

if your snubber is adjustable give it a few more cranks closed. you may always have a bit of bounce my last 12 valve never would quit bouncing even on a mechanical gauge and petcock nearly fully closed.



also if you guage is electric check and see if you can turn the sampling rate down on it. some (like the ISSPRO) have an adjustment for that too.

 

[Rman]

Since we're on snubbers, I just ordered 2 snubbers from chemiquip. I'll let you guys knw how they work. My needle valves will still be there incase I need to shut the fuel flow off, but having them "almost" closed leads to pour performance of my gauge (this is just my opinion). It takes the response away, and like stated above, I still get a jittery needle sometimes. BTW I ordered 2 snubbers because I have a mechanical oil pressure gauge too.

 

[MKizziah]

Isolator???

I used an isolator, which allows you to bleed the fuel side. I placed a petcock on the gauge side and did a vacuum fill with a 100cc syringe of anti-freeze. Thing is rock solid...

Just a thought . .

 

[Rman]

Bleeding isn't really necessary in my opinion, because once the system is turned off, all the fuel drains back towards the bowl anyway, leaving more air. It bleeds itself on startup anyway. Just my thoughts. Bleeding the gauge side of an isolator is a good idea, but it still leaves you right where you started at the end of the fuel side draining back to the filter bowl.

 

[AggieJustin]

I wouldn't worry about bleeding the air. Like the other guys said, it bleeds itself once you start up and let it run a sec. As for running a hose, I recommend it as I've always had at least 12" of line coming from my banjo into the sender and I've never had a bit of bounce.

 

[rweis]

I've had to replace 2 "lifetime warrantee" fp sensors on the VP (Westach has replaced it 2 times without any hassel). I had 18" snubber lines. I am now testing a 120" snubber line not coiled in smooth loops to see if I can get the VP pulse sensations away from the sensor.



Bob Weis