Chevrolet Repair: Chevy S10 Blazer starting problems., chevy s10 blazer, fuel pressure regulator

Question
We have a 1996 Chevy S-10 Blazer with over 100,000 miles.  Recently it became hard to start and now it won't start at all.  My husband (a 'former' mechanic, now electrician) is stumped.  He believes the fuel filter and fuel pump are good.  He just changed the Fuel Pressure Regulator today.  That didn't fix it.  He can get it started by spraying Starter Fluid and then it will crank up just fine for the rest of the day.  But after sitting for a couple of hours or overnight it won't start again.  No problems once he gets it started which makes him believe that it's not the pump or filter.  Any suggestions??  He is totally stumped.  


I've heard from the auto parts store that this is a common problem with this make/model but they say it's a process of elimination and suggest replacing the fuel pump.  My husband doesn't agree.  He says if it was the pump it wouldn't stay running or would put-put like it was running out of gas.

A friend who used to own the same make/model said this happened to his and after changing the FPR he changed the EVAPORATIVE EMISSION CANISTER and that solved it.  My husband is probably going to try this next unless we can get help here.

Thanks in advance!!


Answer
Hi Sonya,

Well, the pump will just cut off, or start but run poorly.  The fact that it will run after starting fluid, I don't suspect the pump yet.  

If you suspect the EVAP system, try loosening the gas cap first.  That may vent you enough to run.  It could be a vaporlock.  

The filter could be the culpret, as could the air cleaner, but I doubt it.  

It is not electical or computer, since these systems don't kick in until closed loop.  It happens cold.  

I have seen the EGR plug up with a piece of carbon on these trucks.  I had a 1994, and for some reason it would develop carbon rocks in the motor.  It would plug the EGR and stick it open.  The truck would act this way.  I had to pull that off to release the rock 3 times in 3 years.  

Naturally, the usual tune-up stuff could cause this too.  I am sure you are past that.  I just had to say it, in case.

Good luck

C J S