Ive been experiencing a no start situation for the last week, to start with I drive an 00 Jimmy, 4x4, 113k. I recently bought the truck with 107k, so I'm not too sure about the maintenance history on it but I haven't had any problems up until now with it.

The problem began last week, I was out driving around all day (in the snow!) and my truck wouldn't start up a few hours after I parked it. We had a huge snowstorm last weekend so I had to have it towed to a shop, they claim that they checked fuel pressure and that they couldn't find a problem, they gave it back to me without fixing anything.

When i turn the key it cranks and cranks with only a slight sputter. I have tried turning the key from off to on a few times to get the system to prime up a few extra times (can hear it priming), but that doesnt seem to help at all. It will start right up when I put some starting fluid in the intake and it runs fine after that. Usually I have about a 3 hour window after running it where it will fire right up on the first try but if i let it sit longer than 3 or 4 hours it wont fire without the starting fluid.

I changed the fuel filter yesterday and it was completely plugged up, I'm not positive but it may have even been the original factory filter (since it was AC delco and the fitting was completely rusted in there). The filter was so plugged up that I couldn't even blow air through it and a bunch of black sludge came out of it when I tapped it on the ground. I'm not even sure how the truck ran before with such a plugged up filter.

I put a can of seafoam in the gas tank and ran it for a few hours yesterday in an effort to clean the fuel system after replacing the filter. This was no help, still wouldn't start up this morning. I'm really hoping that the fuel pump isn't on it's way out. I don't have a fuel pressure gage yet so I haven't checked the pressure but I'm hoping to get one today. I will post back with fuel pressure readings when I get them.

Has anybody experienced a similar problem?

Update:

Just bought a fuel pressure gage,

I'm getting:

- approx 52psi when I first turn the key to prime the system

-approx 50 when cranking

-approx 55psi when engine is running (after starting with starter fluid of course)

-approx 62psi after shutting engine down, then drops to approx 50 within 2 minutes

-primes back up to approx 55psi after

So i'm not getting anywhere near enough fuel pressure to start, is there any other possibilities here other than a shot fuel pump? Any thing else I can check out?

 

The fuel pressure upon starting looks to be too low. Have you had a look at the 96+ Fuel Pressure Test article in the DIY section?

 

Yes, I have checked that thread out but I have a few questions. Can this be done without a scan tool by "commanding the fuel pump on" by switching the ignition to the "on" position to force the pump on? Also, another problem I see will be locating some of the components mentioned.
For example:
- Step 7&16, "fuel pump wiring for high resistance" which wiring should be checked? does the tank need to be dropped to check? what is considered "high resistance"?
- Step 8:, " close the valve in the fuel pipe shut off adapter that is connected to the fuel feed pipe" where is the valve located?

Is there a thread anywhere showing a schematic or pictures of these components to aid in the diagnostic procedure?

 

As far as the wiring, there should be a minimal resistance on the wire. I cannot say a definitive value. Whether you can do it with the tank in or out depends on whether you can get your hand up there and disconnect the electrical harness. I would check the wiring from the fuel pump relay to the fuel pump itself. You are concerned with the main power wire as well as the grounds resistance to a known good ground.

As far as the fuel pipe shut off adapter, that is a separate piece that the dealerships have to adapt the fuel feed line where it connects to the fuel filter to a fuel pressure tester. The appropriate parts can be typically sourced at a good hardware store.

 

UPDATE:

After checking the fuel pressure, i took the truck to my mechanic to have it checked out, his diagnosis was bad fuel pump. The fuel pump has been replaced and the truck is now running perfectly, fires right up every time. My mechanic confirmed that the plugged up fuel filter was likely the cause of my fuel pump failure.

I bought the new pump for $260 and my mechanic only charged $125 to install it, which i thought was a pretty good deal. For any Blazer owners in the Buffalo, NY area check out Steve Stack's Auto on South Park Ave. in Buffalo. He works on alot of blazers and s10's so he knows alot about these trucks, his prices are very reasonable, and he gets the work done pretty quick.

 

Good deal! Thanks for the follow up!