Vapor Lock???

[protour73]

Wow guys, really great responses and ideas. THANKS

The liquid filled fuel pressure gauge is brand new, but I will check it and attempt to equalize the pressure or adjust if there is a screw.

As far as the regulator theory, I don't have one. The fuel lines from where they come off of the hard line are all brand new.

The only performance issue is due to the fact that I have a brand new carb on the car which is not dialed in yet. The car starts fine, idles great.

My theory is that the filter sock on the pickup tube of the sending unit may have been compromised by the ethanol in our fuel around here. I had some serious corrosion issues with a previous Holley Street Avenger (yes Mr. Weld I know!!). I've purchased a new sending unit and will be here early next week.

[intocarss]

Most of the time It's not that the liquid filled gauge goes bad because its new or old,(unless you drop it or beat on it lol) it's that it builds pressure and can give a false reading.

So by backing the screw or removing the plug, you release this pressure. I have used so many different fuel gauges form brand name Co's and they all differ by about 2-3 even 5lbs in pressure. Pick one and tune your engine to it and that is that.

I didn't read that it may be inside your gas tank, I hope it's an easy inexpensive fix for you

[protour73]

Originally Posted by intocarss

Most of the time It's not that the liquid filled gauge goes bad because its new or old,(unless you drop it or beat on it lol) it's that it builds pressure and can give a false reading.

So by backing the screw or removing the plug, you release this pressure. I have used so many different fuel gauges form brand name Co's and they all differ by about 2-3 even 5lbs in pressure. Pick one and tune your engine to it and that is that.

I didn't read that it may be inside your gas tank, I hope it's an easy inexpensive fix for you

The sending unit will require dropping the fuel tank which I don't look forward to. The sending unti was only $70 shipped. It could be worse!!

[Rick D]

Originally Posted by protour73

The sending unit will require dropping the fuel tank which I don't look forward to. The sending unti was only $70 shipped. It could be worse!!

I would try to change the gauge before I would drop that tank? Just sayin!!

[Ron Sutton]

Now I that learn you don't have a regulator in your system, that changes my view considerably.

So, with no regulator, your fuel pressure reads 6-7 ... then drops to 2-1/2. Now, I'm on the same page as everyone else, you either have a bad gauge, or you really do have a fuel system volume/pressure issue.

Test the pressure gauge first.

[Sieg]

Originally Posted by protour73

The sending unit will require dropping the fuel tank which I don't look forward to. The sending unti was only $70 shipped. It could be worse!!

Exactly.......how many cars are easier to drop a tank from?

[protour73]

Originally Posted by Sieg

Exactly.......how many cars are easier to drop a tank from?

The fuel tank is out, replaced the sending unit. There doesn't seem to be anything visibly wrong the old one (had a hunch it would not be the sending unit).

Tank will go back in tomorrow. I'm going to blow out the hard line from the tank up to the fuel pump.

I picked up a cheap (non liquid filled) fuel pressure gauge from the local auto parts store. I'll let the engine idle for as long as it took the Autometer gauge (liquid filled) to fail and compare the two.

I'm pretty sure this $190 exercise in futility will come down to the liquid filled gauge failing, as you guys enlightened me about.

Everyday I have to troubleshoot in my job (manager of technical support team) so I'm used to this.

[Vegas69]

Originally Posted by Vegas69

A liquid filled gauge will become innaccurate with heat. Been there, done that. Order a non liquid filled or a universal gauge and verify before you spend any more time or money.

Not a bad idea......

Just giving you hell Scott.

[protour73]

Originally Posted by Vegas69

Not a bad idea......

Just giving you hell Scott.

HA, Todd I have a pretty thick skin after years of hanging out on these cars sites!! LOL

Originally Posted by Vegas69

Liquid filled fuel pressure gauge in the engine compartment?

But when you posted this I went, OH CRAP, he knows something and that's just the teaser!!

[Rick D]

Originally Posted by protour73

HA, Todd I have a pretty thick skin after years of hanging out on these cars sites!! LOL

But when you posted this I went, OH CRAP, he knows something and that's just the teaser!!

So did you get it back together Scotty??