98 blazer won't start after 18 months of sitting

Alright guys, here's the story. Truck went missing and for 18 months sat in a police impound lot(Thank you michigan police for the quick response). Towed it home replaced the battery, cap + rotor, spark plugs and wires. Added dry fuel and 5gal of good gas (had less than 1/4 tank of gas). Tried to start it, but without success.

Starter cranks good, same as it did before. Tried carb cleaner in the intake and had a few backfires and a few 'damm almost had its'. But really nothing close to a good turn over. Connected my fuel press gauge got 50-55psi (I believe it low) and had a 3-5psi drop after 5 min.

I also checked my spark side. All fuses are good. Checked each output of the distributor with a gap type spark checker, here's what I found: 1) good spark 2) good spark 3) good spark 4) weak spark(had to close the gap to under limits to get a spark to jump) 5) weak spark 6) good spark.

Ok, now a few questions. If fuel press isn't high enough will it not go thur the injectors? When I changed the spark plugs there was no fuel smell on them. Would a bad/clogged fuel filter cause the 10psi press drop that I'm seeing or is it a pump starting to go bad? And what is up with the two weak sparks? It does have a remote start(aftermarket), I'm going to recheck the resistance and wiring and make sure it's not the trucks anti-theft system kicking in. Whatever help you guys can provide is greatly appreciated.

Yes fuel pressure is to low for a cold engine start.
Remove and check/replace the fuel filter.
You need to get the engine cranking fuel pressure up to 63-65 lbs.
Block fuel return line and see if fuel pressure go up to around 75-85 lb or more.
Or check direct fuel pump pressure at fuel filter in line should have 85 or more direct fuel pump pressure.
Just do not run the pump or a couple seconds at full pressure.

Spark output from cap should be the same on all cylinders.
Pull cap and look for cracks in cap or rotor and/or moisture.

Today looked at the cap saw nothing, but replaced it anyway. Now I have good spark all around. I just put a new one 1 month ago, it must of been bad from stock. All well. Next I replaced the fuel filter, still 50-55psi. Now back to the auto parts store, I need to get line/fittings to get a direct pressure reading from the fuel pump. Is there any thing else that would control pressure? Not looking forward to replacing the fuel pump.

Today looked at the cap saw nothing, but replaced it anyway. Now I have good spark all around. I just put a new one 1 month ago, it must of been bad from stock. All well. Next I replaced the fuel filter, still 50-55psi. Now back to the auto parts store, I need to get line/fittings to get a direct pressure reading from the fuel pump. Is there any thing else that would control pressure? Not looking forward to replacing the fuel pump.

Fuel pressure regulator controls line pressure or pressure at fuel rail.
If you can block off return line and fuel rail pressure should jump up to full fuel pump pressure.
But the old direct fuel pressure at filter in line tells the story on a weak fuel pump.
If the fuel pump is weak always replace with the OEM type Ac-Delco/Delphi fuel pump.
Good luck and let us know how it goes.
MT

Since I had everything set up for the fuel filter change, that is where I hook up to. I jumpered the relay to run the pump constant, and direct press reading I got was 55-57max psi. So it looks like a pump change is in my future. When I do it I'll let you guys know how it went.

10-4
On the fuel pump.
Let us know how it goes.
MT

Well, guys I got the pump in. Also replaced pressure and return lines due to rust. On one I did a temp repair to the line and since I had the tank down now was a good time to do it. Still no start. Good news is fuel pressure is back to 60-65 with a short spike to 70psi. Bad news is leak down is immediately (5sec) down to zero. I know that is a bad thing, and I'm going to research this forum to see what I can find. Before I changed the pump I didn't have any leak down, what could I have done to change this. The 3rd line from the pump is it a vent? Any help you can offer will be appreciated

Check fuel pressure regulator.

A shot of carb cleaner and it started up this morning. :) !!!!!!!!! You guys should of seen all the dust that filled the air from the engine compartment after the truck sat for 2 years. How do I check the press regulator and how hard is to change?

On a different note I took the truck around the block and the check eng light came on how do I get the codes without a code reader?

First block off return line and see if it holds pressure.
If not pull plantum and look for external leaks on pressure regulator.
Also pressure can leak back into fuel pump if the cjheck valve is bad.
Pump up fuel pressure and pinch off fuel line from tank to check for that.

To get codes you need a scanner or code reader.
I would run it a little and then check and clear codes and see if any codes come back.
MT