hi everyone
i have a 95 blazer 4.3l 262 that was running bad i replaced distributer cap wires and plugs and no difference so i then replaced the spider and nut kit and what a difference the truck has tons of power and idles good but now i keep getting a p0172 code im told that it could be a 02 sensor how do i eliminate what the problem is.oh and the truck has spark knock untill it warms up and once its warm it starts like the timing is a little off.

please help.

Randy

 

Have you look here yet?

https://blazerforum.com/forum/diagnostic-trouble-codes-dtcs-49/p0172-explained-28942/

 

x2 check you got your wires hooked up to the right plug.

make sure your plug is fully screwed in. a gap from a loose plug will cause problems. Doesn't require 82 fps of torque though...

if you have access to a GOOD scanner, you can peek in on what your suspect O2 sensor is doing. OR try unhooking it and see if the truck runs differently (thanks swartlkk).

Try following the step by step that Sisk linked you to first though.

 

WOW
thats very informative it seems i have alot to dig through.
will one of those hand held units at autozone work for reading the vcm.

Randy

 

well when i changed the spider i used alot of carb cleaner to get the gunk out of there so i could see what i was doing i didnt think any got down in the engine but when i started it the truck smoked really good for about two minutes.maybe i fouled a plug.oh does any one know what the firing order is.

thanks

 

try a little of this action

i flooded my throttle body with a full quart of seafoam. I blew smoke for a WHILE and din't foul a plug. You should be ok with some carb cleaner...

 

ok now when i first start it the ses light will blink on and off several times and go out i think im getting close to solving this.

 

Not to hijack the thread but ya gotta love ABN's updates.. I look for them to make my day.

 

thanks i appreciate the nod

BOT: randy2009, I have my fingers crossed for you man. one out of two runnin correctly aint bad

 

I enjoy them too lol. I loved it what my tow hooks were in his sig lol.

On topic though...it sounds like you're getting closer. Let us know if you get it fixed!