98 Silverado problems with starting

I have a 98 1/2 ton Silvy 4x4 V8 350 vortec. While driving and coming to a complete stop, the engine died. While starting it up, it sounded like it wasn't getting any fuel. After cranking it 2 or 3 times it turned over. Ran pretty good, though my battery gauge was reading between 9 and 14 (shouldn't it be steady at 14?). I got back into the truck an hour or 2 later, it started right up. About a 1/2 hour into the driving, as I came to another complete stop, the engine simply died without sputtering or anything.

While towing it home, I had the headlights on and flasher (because it was dark out) and that lasted for about 20 minutes before the battery was completely drained.

When I got home, I put a new battery in and went to start it up, again, it tried to turn over but couldn't.

Could it be the alternator? (I ruled it out because I've replaced several altnerators before on other vehicles and my truck didn't have the usual "symptons" that alternators cause when they are bad). I think it might be a fuel pump problem. The reason I say this, is because where the back of the cab met the front of the bed, there would always be this humming / buzzing sound that would start up when I turned the key to the on position, but when I turn the key to the ON position, it doesn't make that funny noise.

If this is the case, where is the pump located for the 98's? and is it a beast to change out?

Thank you for your advice.

Odds are that humming/buzzing noise is your fuel pump kicking on when you turn your key. If it doesn't do that, it likely has a power issue (caused by your dead battery). I would highly recommend you taking the alternator off and having it tested, your local auto parts store (Napa, Kragen, etc) will do it for free. Sure sounds to me like it went bad on you.

Odds are that humming/buzzing noise is your fuel pump kicking on when you turn your key. If it doesn't do that, it likely has a power issue (caused by your dead battery). I would highly recommend you taking the alternator off and having it tested, your local auto parts store (Napa, Kragen, etc) will do it for free. Sure sounds to me like it went bad on you.

I'll definitely have it check when I get home from work, Thank you for the insight. I sure hope it is the alt, it would save me a lot of headaches.

So I went and had the alternator tested. The alternator is in perfect running condition. I also had the shop test the batter as well, that too is fully charged and no problems.

I also replaced the fuel filter. When I had the fuel filter off, I turn on the vehicle and no gas came out the line. Now, if the pump was working, wouldn't gas be squirting out? I also check all my fuses as well.

So I am guessing it is a pump issue, what do you all think? Any other ideas before I drop $300.00 for a full pump assembly (since no one here in my city seems to have just the pump itself in stock).

Thanks.

well if its the origional fuel pump you mite as well just go ahead and buy a whole new sending unit cuz you'll be replacing it soon anyway due to age. BTW, my sending unit cost $350 from a local mech. shop.

Since the voltage was low, I would think there is probably a problem with the wiring. Your pump may also be bad, but I would check the wiring for shorts to ground before replacing the pump.

yeah i remember this one time my battery slid over during a turn and shorted out to the fender. it was almost as if it was welded to the fender and i had to pry it sideways to get it off lol. when it happened, my engine obviously died and my power steering went out while i was making a left turn thru heavy traffic. luckily i had 2 dudes with me and we pushed it down the busy street to a fast food joint and ended up just pulling off the battery from the fender and it was all good lol. thats a short circut if i ever heard of it lol

So I went and had the alternator tested. The alternator is in perfect running condition. I also had the shop test the batter as well, that too is fully charged and no problems.

I also replaced the fuel filter. When I had the fuel filter off, I turn on the vehicle and no gas came out the line. Now, if the pump was working, wouldn't gas be squirting out? I also check all my fuses as well.

So I am guessing it is a pump issue, what do you all think? Any other ideas before I drop $300.00 for a full pump assembly (since no one here in my city seems to have just the pump itself in stock).

Thanks.

The fuel pump should buzz for 3-4 seconds when the key is turned on, after waiting for 10 or so seconds.
If you aren't hearing it, then you can try this:
There is a red pigtail wire under the rear of the fuse box, under the brake master cylinder that hangs there not plugged to anything.
Hook a jumper to it from 12v and it is a direct wire to the fuel pump.. So the pump should run. All computer stuff and relays are bypassed.
If someone hasen't mentioned it yet, the pump is in the tank so you would need to drop the tank.
If your fuse/relay box is like my 97, there are three big screws on the rear of the box that will give you 12v inches from the jumper.

Bob B

Thats what my 98 Z71 did just before the fuel pump died............. :sunglasse

Use all the above suggestions first, if you do get your pump to work, see if you can get the fuel pressure reading using a pressure gauge. Should be between 55-60 psi. How many miles? Ever changed your Cap and Rotor? They go bad without much warning, I usually see them with burnt terminals, resulting in a no start, hard start condition.

So it was the fuel pump. Thank you so much everyone for your comments, they helped me go through and help me pinpoint the problem. I was really hoping it was the pump, what a pain to change out. But I'm up and running.

What a great forum!! :grinno:

Hey,
I am having the same problems with a slightly different truck. I have a 92 silverado with a 4.3 L V6. I was wondering if there was any way to check to see if my fuel pump is bad. I have already replaced the fuel filter, plugs, distributer, roter, air filter, with no change. Any suggestions would be appreciated.
Thanks,
Jimmy

Hey,
It ended up being a fried ignition module. If anyone else is having a problem similar to mine, I would deffnitly suggest taking this off and taking it to an auto store and having it tested. It is free and really easy for you to do and could save you hundreds in parts if you just guess and replace parts or take it to a shop. On my truck and similar years, it is located right under the distributer cap. It is held down with two little bolts and has three wire harnesses going to it. just take this piece off and have it tested, might save you lots of time and headache. Thanks for everyones help.
Jimmy Dager