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fuel pressure issues

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Old Dec 20, 2013 | 11:09 PM
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Default fuel pressure issues

drove my s10 347 for the first time this week. we originally set the pressure at 6 pounds. the fuel line runs up the goes to steal braid AN fittings, goes to the fuel log and the by-pass regulator then the extra fuel goes back to the tank through a hard line. but the pressure keeps jumping around on me. we went to start it the other night and had 2 pounds, thought that's weird. brought the pressure back to 6. went to start it tonight and the pressure was at 10. I'm lost . I have just the stock 2.2l pump in it, and I'm probably in the 450-500 fly wheel hp range. how can I figure if its the quick fuel by-pass regulator or the pump? the pump does seem really loud.
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Old Dec 21, 2013 | 06:16 AM
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What kind of fuel pressure gauge? When I first put my car together, I had a liquid filled pressure gauge mounted on the fuel rail. I thought I had all kinds of fuel pressure problems. Got a non-liquid fuel pressure gauge and no more pressure problems. LOL
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Old Dec 21, 2013 | 06:19 AM
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I had about the same thing happen with me. it was the gauge under the hood getting hot from the engine and reading low . If I adjusted it back to 6 psi when it was hot and let it cool off by the next morning It would be high at the pressure gauge. I just adjusted it when it was cold to the correct pressure and called it good. I would check it from time to time when it was cold just after start up. My gauge was an oil filled .

Just something you may want to consider.
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Old Dec 21, 2013 | 02:01 PM
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yepp mines liquid filled. and its under the hood. I bet that's the problem.
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Old Dec 21, 2013 | 06:37 PM
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Your lucky. I bought a new 280$ pump and 40$ regulator cuz of a liquid filled gauge... hopefully yours is fixed. I say everyone should put a gauge on it, set it, run it thru a full pull and watch the gauge to make sure it doesnt drop from lack of fuel, then replace the gauge with a plug. Good luck!
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Old Dec 21, 2013 | 09:50 PM
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yeah we plan on a good high gear pull before we change the pump. trying a new gauge tomorrow.
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Old Jan 1, 2014 | 01:56 PM
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I've been running a Holley Blue pump at the tank and a Holley pressure regulator on the fenderwell feeding a gauge and 4150 carb, same problem. I've read where the Holley regulators will fluctuate with temp changes. I bought a weaker fuel pump to try to fix this psi fluctuation. May end up with a different brand regulator.
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Old Jan 1, 2014 | 02:05 PM
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Originally Posted by kevleetee
I've been running a Holley Blue pump at the tank and a Holley pressure regulator on the fenderwell feeding a gauge and 4150 carb, same problem. I've read where the Holley regulators will fluctuate with temp changes. I bought a weaker fuel pump to try to fix this psi fluctuation. May end up with a different brand regulator.
The Holley regulator is the most used, most successful regulator made. The smartest nitrous guys use them to regulate their nitrous fuel systems because they are so steady. You may have a bad unit, it is not a bad design nor a bad product.
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Old Jan 1, 2014 | 03:59 PM
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I may have been over working my pump but im running a 160 gph pump with 8 am lines to a deadhead quick fuel regulator. Not a single pressure issue after I switched to a dry gauge. Honestly I dont see why anyone would want a return style regulator after ive been running countless hours of hard driving without a single issue. Lots of idle time and lots of hard miles. Zero heat issues with the pump or fuel and zero pressure issues. Just my experience.
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Old Jan 2, 2014 | 10:27 AM
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Originally Posted by 89gmcs15
I may have been over working my pump but im running a 160 gph pump with 8 am lines to a deadhead quick fuel regulator. Not a single pressure issue after I switched to a dry gauge. Honestly I dont see why anyone would want a return style regulator after ive been running countless hours of hard driving without a single issue. Lots of idle time and lots of hard miles. Zero heat issues with the pump or fuel and zero pressure issues. Just my experience.
Any long trips at cruising speeds? Hard drives are suckin the fuel, but a long slow trip may heat the pump up. I had issues deadheading a pump, would get hot on a longer drive and shut off. I just think it would be quieter and easier on the pump with a return. Just preference I guess
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Old Jan 2, 2014 | 01:29 PM
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Originally Posted by snook
Any long trips at cruising speeds? Hard drives are suckin the fuel, but a long slow trip may heat the pump up. I had issues deadheading a pump, would get hot on a longer drive and shut off. I just think it would be quieter and easier on the pump with a return. Just preference I guess
I drove to the track 60 miles each way at about 70 mph with no issues. Ran the track then drove home with zero issues still. Got 22 mpg so it was sipping the fuel then. Woulda been better mpg if I slowed down a little cuz 70 mph is like 3600 rpms lol. No issues ever, the pump (edelbrock quietflo) has a internal bypass that circulates the fuel so that might have helped.
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Old Jan 2, 2014 | 02:40 PM
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I had a liguid guage F me over once too
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