I am currently studying up on the depressive nature of this code and wanted to run the symptoms by you guys to maybe get a direction to focus on.

The issue has started about a month ago, the blazer would buck a bit as it was accelerating past 1st gear and less so past 2nd gear.

This would generally go away after about 4 or 5 stop lights thorugh town on my way to work. Symptom would be gone completely when I get to work. It takes me 10 to 15 minutes to get to work.

I had the codes pulled and I have the P0300 and the code for the fuel level sensor going bad. My light did not turn on through the dash to indicate the code.

I bought the blazer earlier in the year and have since fixed or rather addressed the various issues that it has had. List follows:

1. Replaced distributor cap & Rotors
2. Wires replaced
3. Shocks replaced (monroe Sensa-Trac)

I have cleaned the throttle body as best I could without removing it as I have yet to find the time to go that far. I have also tried to clean the EGR but plan on doing a more thorough job after I replace the spark plugs after work.

My plan is to check the distributor cap and rotor for any abnormalities while changing the spark plugs. After all that and when it gets dark, I'm gonna spray some water on the wires to check and make sure they are still good.

What would you guys say would be my next step shoudl everything checks out with the ignitions issues? Should I get the ignition control module and coil tested as well? I'm currently running a fuel system cleaner through it right now to rule out the easy stuff.

Let me know...I will continue to read up on the random misfire code.

Thanks

Update: Have changed the spark plugs. Too tired to mist the wires tonight though I took the EGR off and gave it a good cleaning. I also looked for the screen to see if its clogged to rule out condensation under the cap though I had trouble finding it. I Will let you guys know tomorrow if it still misses while cold.

 

Update: Just rode it this morning and the hesitation/stumble is less pronounced though still there and seems to happen as it tries to shift out of first.

Is there an easy way to clean the EIP screen on the distributor? Would it require that I pull it out?

Much obliged for the help.

 

replaced the distributor cap as it had white carbon on the contacts. Misted the wires and they are good. had advance auto take alook at the codes again to see if it popped the P0300 code again and it did not.

If it still stumbles/hesitates in the morning then I'm gonna give it a week to see if the code pops up and if it does not then its back to the transmission shop as that is the only thing I can think of why its stumbling. It always does it during 1-2 shift.

 

No stumble or hesitation this morning. I'm gonna continue to monitor it but was happy enough that I cleaned and waxed her this morning . Good girl.

 

Well, the vehicle started doing it again - Misfiring at around 1500-2500 rpm. It just bucks and drags until it pops 2nd gear and then its fine until the next light.

Pulled the cap off and noticed it sparking off to the corner of each terminal on the inside of the cap. Pulled the rotor off and checked again to see if I could find that screen but that's a no-go.

It only happens in the morning and is gone by the time I arrive at work. We have pretty damp mornings her in Louisiana at this time of year (lots of fog). This leads me to believe that the problem is somewhere in the ignition system.

What would you guys recommend my next step would be as I'm a bit lost as to where to troubleshoot next. Gonna go get the codes pulled again to see if it popped a code.

 

Your next step may be a new distributor... They are not too terribly expensive. Go new and not used though.

 

Will do. I'll keep you guys up to date and let you know if it works. What would make a distributor go bad anyways?

 

you have wasted alot of money on this thing when you were going in the wrong direction the whole time!! srry to dissapoint, proper diagnosis is the key to proper repair, if the TRANS is bucking between 1-2 why would it be wires?????? or a cap and rotor, if it were those things it would do it all the time every day and through every shift. And guess what you only have a p0300 code where is the miss fire code, OHHHH wait you dont have one, so why are you spraying water on the wires. YOUR DIRECTION YOU SHOULD HAVE GONE IS IGNITION DING DING DIGN. the ignition switch is part of the TCM and if the ignition switch is bad then hey guess what if the ignition is tied to the trans well.......i dont think i have to explaine anymore, you need an ignition switch there very common on these trucks to go bad

 

Wow. Do you really try to be so condescending when you want to help people face to face?

I'll look into it.

Stay classy dude.

EDIT: I did look it up as per this post: https://blazerforum.com/forum/article-submissions-discussions-47/anatomy-ignition-switch-33465/ (thanks Kyle) and I certainly will look more into it if nothing else works but I really doubt this is the issue.

 

Replaced the Distributor with a reman. The gears at the bottom were definitly worn down as I could tell the difference between the two. I also noticed the new distributor didn't have as much play as the old one and thats always a good sign.

Tomorrow will be the test as it is always damp here in Louisiana. New rotor/cap/distributor will hopefully fix the issue.

I'll report back tomorrow with an update.