Mid 90's S-10 Blazer question

[TR Custom Parts]

Since the S-10 forums don't get much traffic, figured I would post here since we have so many knowledgeable members about just any subject.

I have a 96 Blazer with 131,000 miles in excellent shape. Would pass for a 60,000 mile vehicle. Recently I have been noticing an increase in cranking time before starting. Turns over normally but sometimes takes about 5 seconds to start. Other times it starts right up but the quick startups are now outnumbered by the long cranking startups so I think it is trying to tell me something.

Fairly fresh plugs, cap, rotor, wires. Once it does start it runs normally, no smoking, no smells like flooding and no skipping, erratic idle, etc. Fuel filter was recently replaced as well.

Any ideas?

 

[Otto J]

Most likely the pulsator on the fuel pump sending unit is leaking a bit, Very common problem with s-10s with a vortec motor. Put a fuel pressure gauge on it and check 2 things, Make sure it holds fuel pressure when off (after priming) and also while cranking it MUST reach 55#s of fuel pressure to start, If its only 51 #s very hard start.
They are also notorious for a bad fuel injector

 

[TurboSlacker]

Second the fueling.

I'm with ya, Mark. Our 96 Blazer has 158k miles and still runs and looks great. I'm extremely satisfied with this GM rig.

 

[Drac0nic]

if that doesn't work, try the fuel pump relay. If it goes bad you're starting your engine through the oil pressure safety switch. My little bro's Park Ave will probably be getting another fuel pump relay soon, his is doing the same thing.

 

[myclone]

Originally posted by Drac0nic
if that doesn't work, try the fuel pump relay. If it goes bad you're starting your engine through the oil pressure safety switch. My little bro's Park Ave will probably be getting another fuel pump relay soon, his is doing the same thing.

My vote is that the above mentioned FP relay is the culprit and the FP isnt coming on until youve cranked the motor enough to build oil pressure to make that redundant pressure switch for the fuel pump.

If thats not it then its time to yank the pump out of the tank for a replacement and if so dont use the pulsator (they like to leak) just use the piece of hose supplied with the new fuel pump.

Besides...replacing the FP relay is WAY easier than doing the FP itself so Id try it first no matter what