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Hey my pentax smart head is humming when switched on and the guage is reading 0 psi. The pump is about 10 years old. What's my best move?

Posted by Avind Dattoo on


5 Related Answers


Steve Allison

  • 5569 Answers

SOURCE: Fuel and Temperature Guages

Have your alternator output checked; the voltage regulator might be failing.
You can check it easily across the battery terminals.
You shouldn't have any more than ~ 14.3 volts at any revs., and about 12.6 with the engine off.

If it checks out OK, the next step would be to access any plugs to the instrument panel, pull the connectors apart and then replug them.
You may have a flaky ground under the dash too.

Posted on Jun 30, 2008



  • 3113 Answers

SOURCE: oil pressure guage occassionly drops to 0 psi and warning light g

Get it checked with a mechanical gauge. Replace sensor.

Posted on Sep 28, 2009



  • 14 Answers

SOURCE: Fuel pressure intermittently drops causing sputter and die.

check for 12v constant at your fuel pump if you are not getting that replace your relay.
if you are getting 12 volts at your fuel pump the fuel pump is possible to run tuel it gets warm then shut down to a lower rpm I would then replace the fuel pump

Posted on Oct 10, 2009


  • 64 Answers

SOURCE: No fuel PSI.

Have you tried bleeding the fuel system.
its possible you have an air lock
On the top of the motor is a fuel rail. somewhere on the fuel rail is a little black cap. unscrew it. there will be a valve in it that looks a lot like a tire valve. put a rag over it and with the key on push the valve in to let the air out of the system. fuel will probably come out with a force of about 13 lb. so be careful and ware safety gear. gloves, goggles, ect...

Good luck

Posted on Nov 18, 2009

John P Schwantes Jr

  • 1509 Answers

SOURCE: 95 s10 blazer 4.3

Your blazer has to have 55 psi or better to start and starting fluild is possible to flood the plugs now their too wet to fire. Sit awhile and they should dry on thier own. The injectores won't past fuel below about 40 PSI while cranking the voltage to the pump or the pump ground is going away (starters not grounded good enought and the ground goes positive as the car cranks. Put jumper cables from another running car and coonect them right at the starter ( at least the ground, connect it right o the case of the starter, Pos/ can be connected at the battery). sure your battery may be toast and still crank a good starter but the voltage below 10 while cranking may not close the fuel pump relay al or the ingtion module. I've had this problem and sometimes I've found the ingtion module bad and I had it tested at the store and they said it was good but as I sent it in to be tested they sent a new one anyway and the new module would run it and the tested good old one won't start the car. BUT. Everytime it goes back to the quaily of the fuel pump and I've bought a lot of bad ones for GM products that were made by Master and Airtex. I've never had a problem with a Delphi. As long as the crank voltage is good jump it to make sure and the pump wire while cranking is more than 11 volts and it still has less than 55 PSI you take the pump back get another one or demand the delphi, and if they want you to put in another aixtex ask them to pay you to put it in. Bet you'll get the Delphi. The return level is high on the Airtex and Master pumps is high and the parts guy your buying from knowns this unless he's still wet behind the ears, and plain just does'nt know. Orginal equipment in this area keeps the comebacks away and I'm a pro. unless the customer makes me put in the junk pump I don't even give them a choice.

Posted on Sep 23, 2010

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