# Chevy Silverado-won't start



## used2bcool13 (Sep 24, 2007)

Chevy Silverado 1500 2001, my DH replaced the fuel pump and now the truck won't start, it turns over but won't start.

When the key is turned to the on position, you can hear the fuel pump come on for two seconds, and the gas gauge now works so the pump seems ok.

We also did add gas to the tank so there is gas in the tank.

Any other ideas? It ran before the pump was replaced.

Thanks in advance


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## Travis in Louisiana (May 14, 2002)

Take the air breather off and while someone cranks the truck, see if gas is getting to the throttle body. You should see the gas spray into the throttle body and smell the gas. Also, since you were changing the fuel pump, the fuse may have blown for the throttle body power, ( if there is such a one). Also, I don't know how long you have cranked it, but it may take a few cranks to get the gas to the throttle body. Just my thoughts, I am not a mechanic, just a shade tree one. Let us know what happens.


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## foxtrapper (Dec 23, 2003)

Probably hasn't built up pressure in the system yet, or gotten gas to the injectors yet either. I don't remember where the fuel pump is on that truck, but you can be pretty well sure the lines were drained of gasoline and all pressure was lost. You've got to overcome that.

Generally, crank the truck for a good 30 seconds and it will gradually catch and then run. It'll probably run rough for a few seconds, and then smooth out.

You're hearing the fuel pump do the initial kick. That's fine for a system that is full of gasoline and has residual pressure. Yours does not. That's what you're overcoming by steady cranking.

Alternatively, you can jumper the fuel pump relay or go to the fuel pump itself. Let it run for a minute and then try to start the truck. It still will likely take a little more cranking than normal, but should start up pretty quickly.


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## tinknal (May 21, 2004)

Did the truck run before the pump was replaced?

First place I would look is the ignition module. It is either screwed on to the outside of the distributor, or possibly inside the distributor. You can have it tested at most parts suppliers.


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## mightybooboo (Feb 10, 2004)

Cant you pour a little gas down the throttle body?Or spray it with starting fluid? That should help in getting it going.


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## clovis (May 13, 2002)

Get it started yet?

I once ran a newer Buick out of gas, and it seemed to take forever to get it restarted once I put gas in the tank.


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## mightybooboo (Feb 10, 2004)

Yep,seems like it can be a challenge to restart after fuel system worked on,I recently went thru that same scenario,priming it was the key for us to get it to fire,a couple primes and short 5-10 second runs that way got the pump delivering the fuel forever after.


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## used2bcool13 (Sep 24, 2007)

I had to work the last two days but am off today and we will start try to start, no pun intended, the truck again. I will keep you posted by lunch. Thank you.


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## Beeman (Dec 29, 2002)

Why was the pump replaced? Did you change the fuel filters when changing the pump?


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## used2bcool13 (Sep 24, 2007)

Well back after a depressing day of trying to start the truck, 

Beeman: the pump was replaced because it was failing, the gas didn't read properly on the gauge, the truck was sputtering and I think DH knew it was going somehow. 

The update is: The fuel gauge reads perfectly now and the truck starts if he pours gas directly onto the fuel .......something, throttle body, but it's not getting gas on its own.
DH says the fuel is getting past the filter but not into the fuel ......... (carburetor-like item) - throttle body,

We went out to get a fuel filter yesterday, anyway, but weren't able to get one. We will go out again today for the filter. He feels the line is either blocked/crimped before the fuel ____________ (modulator?) - throttle body and would like to try to take it off but isn't completely comfortable doing that.

For what it is worth, he has taken the fuel tank and it innards out twice just to make sure everything looked ok and it is priming, the fuel gauge is working and he is getting gas past the filter. Any ideas?


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## po boy (Jul 12, 2010)

Blow the line out between the filter and the carb?
Vapor lock?


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## used2bcool13 (Sep 24, 2007)

Well the truck still wont start,

Beeman: My DH knew the fuel pump was going for a while now (however it is you guys "know"), the gauge didn't work, and the truck was sputtering like it wasn't getting gas.

The fuel pump is working (he can hear it priming when I sit there and turn the key), the fuel gauge is (now) working, the truck is turning over but still wont start - after all day of priming the system and trying. 

The truck is getting gas past the fuel filter, and the truck will start when fuel is poured on the throttle body (hope thats the right word). but the truck still won't start independently.

DH says he would like to take the throttle body off and apart but doesn't want to monkey with it too much and make it worse.

We are going to get a new filter today, could not get one yesterday.

If you guys have any other ideas please let me know.


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## mightybooboo (Feb 10, 2004)

Time to listen to the pro's advice,arm chair mechanic me can only make wild guesses now.

Im going to guess fuel pressure problem vrs throttle body problem,plugged or failure. Just my guesses,dont act on em because I dont know.Just want to put my guesses into the thread for when you get it fixed.


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## Beeman (Dec 29, 2002)

Whoever sold you the pump should have sold you a filter at the same time, most pump warranties are void if the filter isn't replaced at installation time. You will need a fuel pressure gaiuge to start diagnosing the problem. This truck is port fuel injected and the injctors are inside the plenum. If it starts when gas is poured in the throttle body then it's a safe bet you have a fuel delivery problem. Either the pump isn't pumping properly, there's something restricting fuel, or the injectors are not firing.


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## mightybooboo (Feb 10, 2004)

Beeman,I dont understand.Is port injected where there is a single spray thing in the throat that sprays fuel then gets sucked into each opening intake valve,or direct injected with an injector per cylinder?


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## Beeman (Dec 29, 2002)

Port is injected at each cyl usually just behind the intake valve in the intake manifold. The fuel inj. that looks like a carb but has 1 or 2 injectors built in it is throttle body injection. Now for the real confuser. All gasoline fuel injections have a throttle body assembly. It is where the butterfly that controls the air flow into the engine is located.
Now port fuel injection can be sequential or all injectors can fire at once and the fuel just waits for the intake valve to open.


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## foxtrapper (Dec 23, 2003)

OK, judging by the confusion on what you're doing, I'd suggest taking it to a shop and letting them fix it. 

If the fuel is indeed getting through the filter, there is no reason to replace it. The filter is not the problem. Though I'd be curious how the determination was made that fuel was getting through it. And, each time you check that fuel filter you get to start the repriming job all over again. 

Did you all do any of the priming or long cranking that was described? You make no mention of it.


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## clovis (May 13, 2002)

Any luck yet?


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## Gregg Alexander (Feb 18, 2007)

pump the gas pedal will send gas from the tank to the engine.


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## oneokie (Aug 14, 2009)

Could be a faulty fuel pressure regulator. As stated earlier, a pressure gauge is needed to test.


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## HermitJohn (May 10, 2002)

I am no fuel injection expert, but from my experience with mechanical injection systems in pre-computer age, fuel pressure is critical and you cant just eyeball it like you can with a low pressure carb system. You need a pressure gauge. I've seen cheap one in Harbor Freight catalog. Make sure it works on your application, think it lists some applications it wont work with. Probably doesnt have the adapter fittings for those applications.

My armchair guess is either its wrong pump for the application or the pump is faulty out of the box. But you wont know that until you can test the fuel pressure.


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## mightybooboo (Feb 10, 2004)

I wonder if it could possibly be the emergency fuel shut off switch?Guess not if they can hear pump run tho.


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## Beeman (Dec 29, 2002)

Sorry, no emer. fuel cutoff on that vehicle.


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## used2bcool13 (Sep 24, 2007)

Hello to all,

At this point the fuel pump is in and working at 50psi, DH also replaced the mass air flow sensor but the truck is still having trouble with idling smoothly. Fuel filter was also replaced.

I think he is going to raise the idle a bit - any other suggestions or ideas? It runs rough, but is now starting and running. Spark plugs, cap and rotor were replaced recently.


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## mightybooboo (Feb 10, 2004)

Get a code reader on it,should give you a lot of clues.


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## Travis in Louisiana (May 14, 2002)

My boss had a Mercury that would not idle. He found out that there was a small valve used to idle the car by regulating the air and not the fuel flow through the intake. This was a small solenoid valve at the throttle body. I know you have a Chevy, but this is what came to mind. You may not have this valve on a Chevy. It seems Mercury could not idle the car smooth enough by regulating the fuel flow, so they used air. Just my thoughts.


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## Bearfootfarm (Jul 13, 2006)

> DH also replaced the mass air flow sensor but the truck is still having trouble with idling smoothly.


At least you got it started!

I'd disconnect the battery and TURN ON the headlights.
I realize that sounds strange, but it drains any power from all the capactors.

Then reconnect the battery and try it again.

The above process resets your trucks computer


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