Author Topic: Gas pressure went adios  (Read 605 times)

Offline shadango

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Gas pressure went adios
« on: July 09, 2009 - 06:38:00 PM »
So after drilling my primary plates last night I was read to test her out.

Well, I started her up in the garage and she ran.....in the driveway she ran.

I noticed that my fuel pressure gauge was reading like 1 psi.

Ok, now its a $18.00 deal from Pep Boys and first thing I thought was "stinking gauge went bad!" because the car was running....never looked at the see thru gas filter.....well, the car ran and made it about 5 miles away to my kids daycare.......on the way home from daycare, right as I pulled onto a major highway (of course) it dies.....wait a bit and eventually it runs enough (almost no idle) to get into a parking lot......

I find the fuel filter is running itself dry. Shut her down and gravity lets some gas back into the filter......

Does vapor lock do this ? I dont think so but ...maybe?

I ran home with the gas cap off but barely running....

...all that would be left is either the regulator is bad or blocked (brand new, installed yesterday), or the fuel pump is taking a crap, right?  Couple days ago it was pumping 6.6 and 7 psi....hence the regulator...now the guage is reading 1 psi when its running......after shutting it down, the pressure creeps up a bit.....

Once the engine cools down I will remove the regulator and see if that changes anything.....

Glad I was only a few miles from home............   :(




Offline Katfish

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Re: Gas pressure went adios
« Reply #1 on: July 09, 2009 - 07:03:26 PM »
Had similiar problem.  Car would occasionally stumble and die.  Wasn't sure if it was vapor lock or not, I don't have a fuel pressure gauge.

Replaced the fuel pump and all seems fine now. 

Offline MEK-Dangerfield

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Re: Gas pressure went adios
« Reply #2 on: July 09, 2009 - 07:06:45 PM »
If you are coming to Carlisle, I can bore you to tears with my tales of woe about my fuel system.   :faint:

If not the fuel pump, then a leak in your solid fuel line...air gets in and UGGA-BUGGA!! Look at the connection from the solid fuel line to your sending unit. Is the rubber hard and dried out? That's another source where air can get in.   :-[

I had some genius brake my solid line in half, and splice with a rubber hose. Fine, until I buy the car decades later when that rubber is petrified wood.   :stomp:

No, if your fuel filter is showing no gas, the problem is somewhere behind it.

Mike

1970 Challenger - SOLD
2016 SXT+.  1 of 524 SXT+'s in Plumb-crazy for 2016.

Offline pink panther

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Re: Gas pressure went adios
« Reply #3 on: July 09, 2009 - 07:42:20 PM »
did you make sure the inlet and outlet are hooked up right? the fuel filter has an in- & out on it, the pump should also
Scott   -  Member since 9/18/2005

Offline shadango

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Re: Gas pressure went adios
« Reply #4 on: July 09, 2009 - 08:26:17 PM »
I replaced the hoses at the sending unit, all the vent lines, etc.

The only rubber I didnt replace was the little piece on the vent line........

My fuel filter is before the pump.......

I removed the regulator and hooked everything back up...pressure is back at 7 psi.

So bad regulator.  Far as I can tell.

On top of that I figured my gas mileage to be a whopping 6.4 mpg....If I did my figuring right.....

My speedo is off by 16.65% compared to my truck (driven along side by the wife) so I adjusted the odometer up that much for the math.

Ouch.  LOL

Of course, thats a lot of idling, testing and running poorly.....as well as one drain of the carb and a couple of the lines in the engine bay.
« Last Edit: July 09, 2009 - 08:34:05 PM by shadango »

Offline CUDA JAS

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Re: Gas pressure went adios
« Reply #5 on: July 09, 2009 - 09:27:28 PM »
ummmm, stupid question...did you adjust the regulator???
74 'cuda 360/727



Gearhead: car nut, automotive enthusiast, one who loves hot rods, muscle cars, hot trucks, burnin' rubber and neck snapping performance. 

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Offline shadango

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Re: Gas pressure went adios
« Reply #6 on: July 09, 2009 - 09:53:14 PM »
LOL....Yeah I did....it was set at 5...I bumped to 5.5 and then down t0 4, etc......

Now that the regulator is off, if I blow thru the inlet side, there is NOTHING out the other....

Not sure if thats the way to check it....

I let the engine sit after running it, to try and duplicate the earlier trip and no issues, aside from my crummy idle and mixture...LOL

Fuel pressure is up at 7 psi.

Offline 6packCuda

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Re: Gas pressure went adios
« Reply #7 on: July 10, 2009 - 07:07:50 AM »
Sounds like you got it figured out. Nice job. :2thumbs:
Dave