leeboy

I just installed one of thoese 30psi westach fuel pressure gauges. I fired it up and it went straight to 15-16 at idle....Then driving it goes to about 10-11 psi ....After a few minutes, it quickly drops down to about 4psi and then works the same as if it was at the 15 psi mark. Full thottle it goes to 0 ps1...But when it went down to 4, it was like someone shut the gauge off. So, i was driving at the 4 psi mark and decided to floor it....The gauge jumps up to the 15 psi again and works fine all the way home. Its like it dows this everyday after i fire and drive for a few minutes.....But then flooring it, brings it back to the 15psi and it doesnt jump back down til i shut the truck off and it cools off....I have the gauge double grounded and all connections are tight. I dont want to buy a new lift pump if i dont have to. I have no symptoms of dead pedal or loss of power....Ideas?

PourinDiesel

Check the pressure manually.

I am having the same problems with my Westach fuel pressure gauge right now.

I messed with some of the wires that attach to the sender and now it only reads 30 psi whether the FASS is running or not.

It probably needs a new sender but I will check fuel pressure manually in the morning.

JD730

2nd on manually checking the fuel pressure.

leeboy,
I'm guessing you still have the stock lift pump, have you ever replaced it? I had one give me similar results. Fuel pressure would drop while cruising and if you floored it the pressure would go up. I attributed it to a flaky bypass valve on the pump.

PourinDiesel

Update:
Checked mine manually this morning. 30psi+ of good fuel pressure.
Either my Westach sender is bad or there is short/bad connection somewhere in the wiring to the sender.

leeboy

Hey guys, ya i have the stock lift pump still...I am going to pick up a manual gauge this weekend. I guess, i will tape it to the window wiper or something and see if they match....

mcoleman

The sender is probably bad.I went through 3 or 4 senders doing the same thing before I ditched mine and went with a diprocal mechanical guage with a needle valve and no isolator 3 years ago. No problems since.

Barney

Is the pressure transducer remotely mounted?

If its mounted someplace where the engine vibrations can hammer it, there may be problems. I remotely mounted mine, when I installed them in AUG of 2000.

leeboy

Nice Job, mines just simply screwed into the filter housing...

musthave

use a ohm meter and check resistance on your sender to ground it should vary depending on your pressure. Open lead to the gage will read 0 ground that lead it will read max.

leeboy

I havent found a cheap manual fuel gauge yet....What i did notice was, once the psi drops to 4psi, if i shut the truck on and tunr back on...it goes right back to 15 psi for a while...or somwtimes the whole ride...

riwamiya

Did you ever find a solution to this problem?

olddodgetrucks

if you in Can. Princess auto has hyd pressure guage on sale 2 weeks ago $4.99 0 to30 lbs and you can buy 10 feet 1/4 of hyd hose for about $10 to attach it.

leeboy

I bought a $20 gauge and screwed it into the other side of the fuel filter canister. So, when one went down to 4psi, so did the other. So, it doesnt look like a gauge problem. I ordered a new Fass DDRP that is goin in tomorrow, so that should fix that gauge...