HELP! Blazer will not start..

[heyraver]

1997 S10 Blazer 4.3

Hello everyone,

My blazer will crank over but will not start.
The truck recently had problems with misfires and running really rough while cold, but would run fine after the motor warmed up. The truck always ran smooth in idle, but once you gave it gas, it would misfire and shake like crazy. Sometimes my RPMs would jump to 1500 then stall out right after. Occasionally, i would get white smoke from my tail pipe, but only when it was moist outside. While driving, I was also hearing 'popping' sounds coming from my exhaust as if it was backfiring. There is normally water dripping from the tailpipe.
When the truck misfired, I would get the P0300 misfire code and the codes would turn off once the truck warmed up and stopped misfiring.
I tested the fuel pressure today and come to find out that my truck will not start now

Oh yes, what I found odd was that when I was cranking the motor and getting no start, when I would switch the ignition to the "off" position, the motor would 'jump' for a quick second as if I was cranking the motor over.

Here's what I have for readings on fuel pressure:

Key On, Engine COLD off: The gauge jumped to 63psi then rested at 55psi

After the pump off for five minutes, the gauge simmered to 50psi

While the motor cranking, the gauge remained at 63psi

I hope I was detailed enough and hope that I
get any kind of feedback from you guys.

Any tips or advice is greately appreciated.
Thanks again.

[old_master]

Stick an AC Delco distributor cap and rotor on it. Put a dab of silicone dielectric grease on each terminal, inside and out, of the cap.

[heyraver]

Thank you for your feedback!

I was recommended by a few people to change the cap & rotor.
Would a bad cap & rotor really cause a truck to not start up?

Do you also know where I would find good deals on AC Delco products?

[old_master]

Bad cap will absolutely cause a no start, and backfire, and rough idle, and misfire on acceleration, and cause the SES light to come on, etc etc etc. Don't waste your time or money on aftermarket caps or rotors. Do it one time, with the right parts, and be done. Check eBay or do a search for AC Delco dealers in your area.

[heyraver]

Thanks for the info again.

I'm going to pick a cap and rotor right now.

i'll let you know how it goes.

[heyraver]

just changed the cap & rotor and the truck fired right up!

thanks again for the help

[old_master]

Glad you got her going, and thanks for posting back!

[Rick Norwood]

Originally Posted by old_master

Don't waste your time or money on aftermarket caps or rotors. Do it one time, with the right parts, and be done. Check eBay or do a search for AC Delco dealers in your area.

ABSOOOOOOOOOOOOOOOOOOLUTELY! LISTEN TO OLD MASTER!!!

Never put anything but an AC Delco Cap and Rotor on any GM Vehicle. You will thank him later.