1994 S10 Blazer Won't Start - 4.3 Vortec

My son left work (50 miles away) and said when he gave it gas it felt like it was dying. He was just about home and it died, so I had it towed home.

A year or so ago I replaced the fuel pump so I figured it was a fuel pump problem again. Two years ago I replaced the Spider. My problems with this car have almost always been fuel related.


I hooked up a fuel pressure gauge and it goes to 62 right away then drops to 58 when the pump turns off.
I checked the spark at each cylinder and it is getting spark at each.
I took one plug out of each side and they looked fine, dry and not all gumed up (thinking if the spider was a problem one side would look different than the other).
I took off the distributor and nothing looked wierd. A little worn but nothing out of the ordinary (although I don't remember when I changed it, and the rotor)


There was only 1/8 of a tank of gas so I thought maybe the gauge was screwed up so I put in a gallon of gas. It started but ran really bad, then I let it down too low, it died and won't start again. It shows more gas on the gauge now but this really bugs me I am thinking maybe somehow bad gas or something, but it ran fine according to my son up till it went down to 1/8 tank.

I am kind of struggling thinking it has fuel pressure, so fuel is fine. It is getting spark so that is good. I changed the fuel filter last year when I changed the pump, and with the pressure tells me it must be OK. Well I have to be missing something. I am thinking of going down and getting a few more gallons of gas but I only have a one gallon container and just doesn't seem logical, as there is at least one gallon in the thing.

Thanks in advance for your help!
Dave

That 1/8 of a tank could be water or has water on the bottom. Disconnect the fuel filter and run some gas out in a jar and look at it.

Or, add a bottle of heat to the tank and make another 4-trips to the gas station with your 1-gallon can and see if it will then run.

Let us know what you find.

What is "heat"? Some sort of additive to help it get going?

I just emptied out the tank and the gas looked OK, but I ran it down to nothing then put it three more gallons of gas. I also changed the fuel filter, since I had it. Does it need to be primed in any manner or should it just fill up with fuel?

It is getting spark, so I am really thinking it has to be fuel. I'm wondering if the spider can fail in this manner? My previous problem with the spider was on 1/2 the cylinders. With pressure of 62/58, if it is fuel seems like it could be past that and the only thing is the spider (I think). Should I see gas on the plugs when I take them out (because I don't)? Is there some way to check the spider other than replacing it? Do I need to open it up to see if there is fuel?

Dave

Heat is an additive to displace water in fuel. Commonly used in cold climates to prevent condensation or ice from forming in fuel tanks.

I would also think the plugs should show signs of fuel on them. What color is the spark, yellow or white? It should be white.

I would say the next step is to see if the injectors are firing.

Does your vehicle have a Z or W in the Vin number?

A special test light called a noid light can be used to determine if a fuel injector is receiving its proper voltage pulse from the computer to fire it. However, you may have to remove the upper intake before the noid light can be used. In which case you may be able to pull an injector and visually see if it's firing or not, depends on what type injector system you have.

I suggest picking up a shop repair manual and it will tell you how to test the fuel injector system.

I'm not that familiar with '94's, so maybe someone else will jump in here.

Mission Accomplished! :bananasmi

Just put in a new Spider and I'm back in business.

This afternoon it started again for a minute, but really bad, so I was convinced it had to be fuel. I took off the Plenum and it was all washed out. I should have done it earlier since it isn't that hard, but it is easy to say that after the fact.

Thanks for your help!
Dave

Great - I love happy endings.