Hi everyone!

I'm new here, and I have a 1993 4.3L Vortec Chevy Blazer 4 door.. vin W that my I inherited from my father. I don't know how much more starting information you need, but I'm willing to find out.

I'm a complete noob when it comes to all things auto/mechanical. I am learning, though, so please bear with me. (I did change the alternator for the first time by myself a few months ago, hooray for me)

Here's the issue. A few months ago, I noticed whenever I'm idling at a stoplight or something like that, the truck would struggle to stay running, it would throttle up and down and sometimes it would just die. But it would start right back up. I've since, at the suggestions of some of my friends and some people at the parts store, replaced the fuel filter (the one near the side, not the one in the tank) and ran some fuel injector cleaner in it periodically. This seemed to clear up the issue, but now something else is happening.

The truck seems to run fine in the morning or whenever it's been sitting for a few hours. It starts right up. But when I drive it to work or any considerable distance, I notice a very strong fuel smell when I park it, or it's idling at the light. Very recently, the check engine light comes on when I idle now, and if I try to start the truck up shortly after it's been running for a while, there is a whining noise coming from the fuel tank area in the back, and the pitch of the whining noise raises and lowers with the throttle.

When it's whining like that, I can barely make it 5 to 10 feet without it dying. But it will always start right back up, and if I keep a little throttle on it, it will drive ok after it's been idling for about 15 minutes.

Is that enough information?

I'm guessing it's something to do with the fuel pump, but I want to make sure (or at least have a better idea) before I go down and pick up a replacement part.

Any ideas would be appreciated. Thank you so much!

 

you need to get ahold of a fuel pressure gauge. Go by autozone and ask for the loan a tool gauge. Its free,but you gotta leave a deposit in case you dont return it. Buy a haynes manual etc to give you some help while working on the vehicle. You need to locate the fuel port to test the pressure at which is behind the intake manifold. Needs to be around 56-60 psi and HOLD above 55 psi for 10 minutes. If it steadily falls its either the spider assembly or the valve in the fuel pump. Test the pressure at the inlet of the fuel filter too,if it holds its the injection spider,if it still steadily falls its the pump.

If its the pump,Please dont give yourself more trouble. Go buy a ac delco brand pump at the dealership,or rock auto. Aftermarket pumps dont work well with these blazers. For the spider,if thats the issue I dont think brands matter as ive never heard much about new faulty spiders.

 

Get the CEL read at auto zone or who ever reads them for free & let us know what the code is or look it up & post a link.
I lean towards a catalytic converter issue &/or O2 sensor... but the check engine light CEL will tell us more.
If you get under the vehicle while it's running & hit the cat & it rattles... it probably needs to be replaced.

 

rotti,remember your in the 1st gen section lol he has obd 1,autozone etc cant pull obd 1,just obd 2.

OP,if your engine lights on,google "obd 1 gm check codes" and read some tutorials on how to check codes with a paperclip.

 

Thanks! I'll try that, and let you guys know.

 

WHAT doesn't everyone have a 2nd gen now? lmao
Yeah I remember jumping 2 'pins' on the connector & reading the flashes of the CEL & matching it like a Morse Code for cars.

 

I know AutoZone doesn't have the tools to test my truck, but I'm pretty sure O'Reilly's does, they've done it before.

 

So, I replaced the fuel pump, and it seems to be a little better.. no more whine from the tank, no more issues if it's hot. My radiator cracked a week ago, I replaced the radiator and water pump as well.

Here's the issue now. It seems to be running a little better, but it idles VERY high when it's in Park or Neutral. Doesn't matter if it's cold or hot, the engine revs very high and sits there, and it turns my check engine light on at lights or when in park. I haven't had a chance to check fuel pressure, but I am also wondering if it might be the TPS?

 

Vacuum leak?!

 

I would also check the EGR valve. It sounds as though you may have a lot of carbon in the intake manifold which is flaking off and jamming up the EGR valve. I had that exact same problem with my '93 Sonoma when I bought it. I had to clean out the EGR passage several times and eventually install a screened EGR gasket to keep the carbon flakes from sticking and holding the EGR valve open.