Take a guess on the problem

Walk around the rig when it's full hot and key off. A leaking spider/poppet injector will make it reek of fuel just minutes after shutdown. Also as other keen minds noted, suspect a clogged inline filter. And/or check fuel pressure at key-on, engine off... and how fast (If you have a pressure gage attached) it leaks down.

If it leaks down fast, suspect a poor check valve in fuel pump, these trucks eats them and fuel pumps and regulators like candy.

Remove upper intake and inspect. If you see gold colored washing, while everything has a good patina of oil... suspect fuel regulator and poppet Assy. leak... it can happen in the hoses leading away from the spider injector.

If you service any top end injection, or even suspect the tank sender? Still... just overhaul the whole system from sending unit, sock, inline filter, FPR and the spider injecting set. Only because a lot of it is simply plastic and Teflon that gets old and crunchy over X-years. A fix/upgrade anywhere along the line can stress and break aged components.

After I fixed mine from tail to nose? I could have welded the engine lid shut. I had a leaky Fuel Pressure Regulator, and a poppet tube. So I grabbed those up, an inline filter and a fuel sending module with new pump and sock. Never looked at it again in the decade after until the truck was totalled out from under me.

Edit: The ignition system on these are pretty robust. If the wires are old and cracked looking when you fold it over a finger, replace. If plugs are worn, replace. If the rotor button and/or cap look to be carbon traced or cracked, replace.

But the biggie is if it stinks like gas after a hot run and a few minutes after letting it rest. If you smell the hot, heavy stink of fuel, do a full fuel injection service. Follow with tried and true ignition tuneup. A full plug, wire, rotor and cap swap. Wait... you said 2002?

I'm thinking 1995. A hard start or several key-on-key-off cycles could get a weak spider/FPR to build up until it fired. A 2K2 is likely port fuel injected. No more spider. But much diagnostics are the same. You need a hair under 58psi for it to catch and fire from the FSM. No more cap and rotor either. Likely a plug near coil setup akin to LSx series engines. These are Tonka tough, yet a bad plug, coil pack or shorty ignitor wire can make them hard to start... or trigger misfire at high speed.

If not suffering from low compression, low fuel pressure and/or fuel pressure bleed; then start testing the actual full operating pressure of the system. Easily tested by removing the vacuum line from the FPR and letting it hit full operating pressure. (60 PSI @ Idle)
Thank you for an interesting post.
But I don't work on my vehicles anymore(age related) my go to mechanic now is Mr. Plastic.
 
Fuel pump or injector system. Can you hear the pump prime when you turn the key to on but not crank it?
 
my go to mechanic now is Mr. Plastic.
LOL true and funny at the same time!

My vote is plugs cap and rotor. Had numerous vehicles in the past that ran fine when it was dry but acted up when wet. PC&R fixed it every time.

When it's hot, moisture gets burned off so no barrier to good spark.

Not saying it couldn't be the "fuel spider", but with occasional check engine light I'd start inexpensive. No sense working Mr Plastic too hard.
 
Probably the injection system. But at 108k, it needs cap and rotor, spark plugs, and wires. I would clean the MAF and replace the upstream O2 sensors. Replace PCV valve. Inspect all vacuum hoses and replace what looks bad.
 
Probably the injection system. But at 108k, it needs cap and rotor, spark plugs, and wires. I would clean the MAF and replace the upstream O2 sensors. Replace PCV valve. Inspect all vacuum hoses and replace what looks bad.
The shop said to bring it in for a look see before throwing parts at it.
Probably needs all you said but we will see.
I have no problem if they replace all that,I got the vehicle for free.
 
The shop said to bring it in for a look see before throwing parts at it.
Probably needs all you said but we will see.
I have no problem if they replace all that,I got the vehicle for free.
So....what did it turn out to be?
 
My guess is the spider injection as well. I mentioned it back on this thread as well. I hope everything goes well with the repair (whatever it may be).

 
Shop said it was a bad fuel pump.
They are going to replace it and the fuel filter.
I hope they are right.
 
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Shop said it was a bad fuel pump.
They are going to replace it and the fuel filter.
I hope they are right.
I have been through quite a few fuel pumps on the S10/ Blazer/ Bravada. I suspect your shop is correct.

Hope the corrosion is not so bad on the Blazer. Brutal design on the fuel pump placement on the Blazer. Salt can get on top of the fuel pump mount, but can't escape. All of GM's cheap fuel pipe just sits in salt, it can't escape. Same design since the 80s and GM never corrected this disaster of a design.

Don't be surprised if the Blazer was in a salty area to need a new fuel pump mounting ring, new gas tank straps, and more.

Of note, on the S10, the ground for the fuel pump is made of the thinnest wire known to man. And this ground connects at the rear of the truck bed, and is also subject to corrosion. On a S10, one should also check the fuel pump ground for intermittent starting or dying while driving. In my wildest dreams, I can't imagine why GM used the very slimmest of wires taking the farthest run possible for a fuel pump ground.
 
I have been through quite a few fuel pumps on the S10/ Blazer/ Bravada. I suspect your shop is correct.

Hope the corrosion is not so bad on the Blazer. Brutal design on the fuel pump placement on the Blazer. Salt can get on top of the fuel pump mount, but can't escape. All of GM's cheap fuel pipe just sits in salt, it can't escape. Same design since the 80s and GM never corrected this disaster of a design.

Don't be surprised if the Blazer was in a salty area to need a new fuel pump mounting ring, new gas tank straps, and more.

Of note, on the S10, the ground for the fuel pump is made of the thinnest wire known to man. And this ground connects at the rear of the truck bed, and is also subject to corrosion. On a S10, one should also check the fuel pump ground for intermittent starting or dying while driving. In my wildest dreams, I can't imagine why GM used the very slimmest of wires taking the farthest run possible for a fuel pump ground.
This Blazer has always been in Colorado where salt is not a concern.
 
Picked up the Blazer today and it seems the new fuel pump gives it a bit more acceleration and it runs smoother.
They installed an AC-Delco pump 0acp MU1733.
Hope it last awhile it wasn't cheap.
 
Picked up the Blazer today and it seems the new fuel pump gives it a bit more acceleration and it runs smoother.
They installed an AC-Delco pump 0acp MU1733.
Hope it last awhile it wasn't cheap.
I know it is a pricey repair, but you had it done under your terms and conditions. The fuel pump on the Blazer is a high failure item, and it could of failed on the interstate far from home with a full tank of fuel. And the random shop may have put a aftermarket fuel pump in, that lasts just a few months. You had this done without being stranded!!

To the best of my knowledge the Ac-Delco and the Delphi pump have been revised to include better amp flowage of the 12vdc, thus reducing the main reason the OEM pump was prone to fail.
 
I know it is a pricey repair, but you had it done under your terms and conditions. The fuel pump on the Blazer is a high failure item, and it could of failed on the interstate far from home with a full tank of fuel. And the random shop may have put a aftermarket fuel pump in, that lasts just a few months. You had this done without being stranded!!

To the best of my knowledge the Ac-Delco and the Delphi pump have been revised to include better amp flowage of the 12vdc, thus reducing the main reason the OEM pump was prone to fail.
New fuel pump and fuel filter was $1149.00 with tax
Total cost with above plus diagnosis, new wheel stud,oil and filter was $1425.00, with tax.
If it failed on the road add another $125 to $150 tow bill.
 
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