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greetings everyone. Yesterday I was messing around with the car and foul something up. I was trying to figure out which fuse controls the trunk light as now I am not getting a 12-volt signal inside the trunk. All the other lights are working just fine. I have a bigger problem now however, I was fiddling around trying to get my underhood light to work as I was not getting any 12-volt signal from it since I bought the car. I checked the fuse box and notice that the fuse for the air pump was missing so I installed one and the light is working fine now. I start messing around with the trunk light and I actually cut off the connector that is back there because I was going to rewire it with a newer brighter LED set up. Come out to mess with the car this morning try to turn it on and it will crank and crank and not turn over? Fuel pump fuse is intact, I'm about to go grab a fuel pump relay to swap that out, I also tried running 12 volts directly to the red wire near the fuse box which is supposed to be the fuel pump PrimeWire I guess and I don't hear the fuel pump kicking on. Car was riding 100% yesterday never any issues with the fuel pump. Any thoughts?
 

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Hey bud, what year you got.

Only thing that makes me suspicious about what you did in the trunkus is the attached wiring diagram that shows that the ground for the fuel pump is in the "luggage compartment." This would explain why 12v direct didn't do anything.

Seems like you would have seen one of the other lights this controls not working, but I'll mention it anyway.

I'd go backwards, undoing everything you did and see if it starts. Then re-do things one by one till you get back to zero.

Seems weird to just coincidentally have the fuel pump go out, but weirder things have happened...


greetings everyone. Yesterday I was messing around with the car and foul something up. I was trying to figure out which fuse controls the trunk light as now I am not getting a 12-volt signal inside the trunk. All the other lights are working just fine. I have a bigger problem now however, I was fiddling around trying to get my underhood light to work as I was not getting any 12-volt signal from it since I bought the car. I checked the fuse box and notice that the fuse for the air pump was missing so I installed one and the light is working fine now. I start messing around with the trunk light and I actually cut off the connector that is back there because I was going to rewire it with a newer brighter LED set up. Come out to mess with the car this morning try to turn it on and it will crank and crank and not turn over? Fuel pump fuse is intact, I'm about to go grab a fuel pump relay to swap that out, I also tried running 12 volts directly to the red wire near the fuse box which is supposed to be the fuel pump PrimeWire I guess and I don't hear the fuel pump kicking on. Car was riding 100% yesterday never any issues with the fuel pump. Any thoughts?
 

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So I got the trunk light working again was just a blown fuse car still won't start though. I still have fuel pressure, pushed in the Schrader valve up on the fuel rail plenty of gas came spewing out. I guess I have to start checking for spark next.
 

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So I got the trunk light working again was just a blown fuse car still won't start though. I still have fuel pressure, pushed in the Schrader valve up on the fuel rail plenty of gas came spewing out. I guess I have to start checking for spark next.

IMO your fuel pressure test procedure is killing me ...LOL..
 

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I still have fuel pressure, pushed in the Schrader valve up on the fuel rail plenty of gas came spewing out.
Obviously not the best way to check for Fuel Pressure and not very accurate or safe. But sometimes that will at least tell you if you got Fuel to the rail. Just be sure to use a Rag over the valve to keep the fuel from spraying all over you and "I" would only do this on an Engine that is not running.

If you happen to be on the Road and break down like I did with minimal tools and no Pressure Tester in your toolbox, this will work. Most times you can listen for the Fuel Pump running and assume you have gas going there. However, if your off the shoulder broken down like I was with Cars/Trucks zipping by you at 70+ its real hard to hear if the pump is running. In that scenario, I used the Rag over the valve method. Sometimes you just gotta get a little MacGuiver like.
 

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Glad you were able to fix it. Here's an interesting observation that may be useful:


If you apply 12v to that fuel test connector (red wire, black connector) that dangles near the fuse box, you will turn on the fuel pump on it's own without the engine running. The benefit to this is that you can then "hear" the gas running past the fuel regulator and back into the gas tank. If you don't hear this sound, your pump is likely weak (under the regulator pressure level).



Why is this handy? Well, you can't hear this sound with the engine running (too much noise) and you can't otherwise keep the fuel pump running with the ignition key on as it only primes the fuel rail till the engine is running. Catch 22.


Again, so why is this handy? Because if you can hear fuel running past the fuel regulator (assuming the fuel regulator is good) then you know that your fuel pump is capable of hitting the 40+ pounds needed to cycle past the regulator and give you enough fuel for hard acceleration or passing or climbing a hill. If you cannot hear the fuel flowing, then your fuel pressure is likely weak and while the car will seem to run just fine as a daily driver, you are actually starving the engine of fuel when accelerating hard. If you are observant, you will say, "Hey, I'd swear my car used to accelerate faster ... or it felt like it did." Cause it did actually.



So ... why doesn't the car stumble if the fuel pressure is a bit low (say 30 lbs)? Doesn't it run out of gas? Nope. Car will idle and run fine around town with only 24 lbs. Mostly because it's a computer controlled fuel injected engine. The engine will self limit it's power. If the injector burn can keep increasing the air intake, it will keep accelerating. If the burn is limited by the fuel pressure, it simply stops accelerating (pulling). To a degree mind you, if your fuel pressure is under 20 lbs say, you will notice all sorts of problems even around town. Our cars do need a minimum power capability to move their fat asses even on level ground.



That said, a fuel pressure gauge is the best way to know if your pump is strong enough.



*Note that a new fuel pump will sound like a faucet at the rails and as it ages and gets weaker, that sound becomes weaker. When you hit the regulator limit, the sound goes away.
 
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