Started having problems a few weeks back.

Blazer would start in the morning, but stall after putting it in gear. I'd let is sit for ten minutes, re-start and it would run/idle fine. Later in the day, it would stall at stop signs, etc. Had to put in neutral and keep the gas pressed to prevent stalls.

Now, it cranks (battery very strong) but zero fire.

I can hear the fuel pump hum when the key is turned on.

Suspect it's fuel filter, but not sure. Would a bad distributor cause this?

 

Just because the fuel pump hums doesn't mean its putting out enough pressure. These engines require quite a bit of pressure to start and stay running. This would be the first thing I would check. Use the 96+ fuel system diagnose on this forum.
https://blazerforum.com/forum/showthread.php?t=45941

 

Thanks. I'm a weekend warrior with limited experience/tools so it'll probably be a mechanic visit.

 

I understand. good luck and please let us know what you find out.....your problem and fix might help someone else out!

 

Roger that. I may be able to figure out how to test fuel pressure via the Schrader valve. Will advise.

 

OK.. I've been on the road on a project (without my Blazer, unfortunately.)

Just got back in town,and had a mechanic friend look at the Blazer. It would crank, but not fire, so he he used starter fluid and it fired right up and idled for several minutes. When it's turned off and re-started, it acts like it's flooded and barely starts.

This is what he determined, thus far:

- Fuel pump and filter are in perfect working order, plenty of gas coming up the fuel rail.
- Electrical is good to go.

He's guessing it might the spider valve, which is about a $600 fix.

Another ideas as to why it might be flooding out? Maybe a bad sensor, or other part? Just doing final research before I commit to the spider valve.

Thanks.

A quick search show similar problems with this series. Do any of the following seem possible culprits?

- MAF (Mass air flow) Sensor
- Idle Air Controller
- EGR (Exhaust Gas Recirculation) Valve

 

What does "plenty of gas coming up the fuel rail" translate to in PSI at the fuel pressure test port?

 

swartlkk:

The pressure is 60 psi when the key is turned on, but not cranked.

It's been five hours since we last ran it, and I just tried it again.

It's back to cranking but not firing. It seems like it would start if it were only flooded....

 

Does the pressure bleed off fast?

If there is a leak inside the intake plenum, the priming of the fuel pump could instantly flood the engine.

 

Unknown. Will have to have my mechanic friend check it again for bleed off.

It ran like a champ for ten minutes when he started it with starter fluid. We turned it off for fifteen minutes and then tried again, and it started on its own.

I then returned to work and five hours later, nada.

Should I look anywhere specific in the intake plenum? (Sorry, I'm a weekend warrior and my knowledge is limited.) I've read through the threads and thought I'd try cleaning the MAF sensor.

In any event, thanks for getting back.