just a goofy thought-with a scan tool what is the temperature that the temperature senson is sending to the computer at start up? If that were messed up and reporting wrong then the computer would richen or lean out the initial fuel mixture thus....causing an issue. Just a thought and one that won't(hopefully) cost much, if anything-depending on the availability of a scan tool. JP[X(]

 

You mean the intake air temp sensor? That might be possible to do(get access to a scanner).

As for the fuel pump, yes i put the guage on yesterday morning while it was acting up and had 60psi.

Last night swapped the 2 week old battery from my 5.7L Z28 into the Blazer and this morning it fired on the first try... it laboured for a split second but nothing like it usually does. This battery has 630 cca instead of the 600 my other one had. It was 2 degrees above zero here so cold enough to be in the range where it's been acting up. I'm going to wait a couple mornings to see if this was a fluke because i've had fluky days where it's worked before.

Fingers crossed

 

how old is the 600 C/A battery to the 630 C/A one?? I`m still goin with the temp of the weather your having being the battery the culprit,,, Not enuff juice to spark it right...

 

I dont' know actually. I bought the blazer in april and this is the same battery that was in there(600). The 630 is 2 weeks old.

I hope this is it...i'll post up in a couple days after a few more cold morning starts

 

if its the battery from 1999 get a new one without hesitation...I have a battery in my elcamino that i bought quite a few years ago... Its no good now from just sitting but it had 1000 CCA to it,,, My el had a 454 with 600hp in it and it started the thing like it was butter on heated knife..

 

I have no idea how old it is

 

if your able to to see on the side of it somewhere, they sometimes stamp a date into the casing of the battery..or it may be on the sticker that should be on top of the battery with the name

 

Cool thanks for the help. The battery is out of the truck now so i can check it for a date.

 

Update: I dont' think the battery is the issue. It started fine all weekend but it was up around 12 degress... this morning it was 4 and had dipped below zero through the night and it stumbled starting...took me three tries to get it to fire. It's supposed to be a cold week here so i'll know for sure in the next couple days but i think my search continues.

I did an oil change and added some fuel injector cleaner over the weekend as well.

 

i have a very similar problem with my 98 blazer. i put a charger on it and it cranked right up. so i put my new optima battery out of my chevelle and it didnt help much. still takes a few tries in the morning to start.mine might be a fuel pump problem. i have checked fuel pressure numerous times. pressure is over 60 except when it sits for a day or overnight. then i always have a pressure problem and struggles to make it to 55psi. but once it starts(and runs perfect) then drive it for a bit and pressure is great the rest of the day. i have done a full tuneup including a fuel filter and am down tothe pump now. not unless its wiring . hard to tell at this point.ive ran injector cleaner numerous times through the fuel system and doesnt seem to help. mine however is not affected by temp..just how long it sits.