Is my CPI going bad

I have a 95 S10 Blazer 4.3l CPI. I have a slighly rough ideal. Also when i am just starting to accerlerate (exspecially going up a hill) my truck shuders and i have to give it alot more gas to make it stop shudering. could this be my CPI going bad? please help me out guys, thanks.(exuse all the bad spelling)

Its possible. But before you go and replace your CPI, you should check a few other things.
1) Pull your EGR and make sure you don't have any carbon chunks that mite be blocking the plunger from moving freely. This could cause the symptoms your having.
2) Check your fuel line pressure to ensure that you have between 62 - 65psi with your ignition switch on. If not, then you probably have a bad fuel pump.
Click below for more info on CPI troubles:
http://www.automotiveforums.com/vbulletin/search.php?searchid=1244460

Ever done a tuneup?

I have a 94 jimmy w/ 4.3 vortec 183 k miles and also had the same rough running condition last summer, replaced the cpi, cleaned egr valve etc. This cured the problem..then out of nowhere friday eve the same probs returned only worse, very bad vibration @ any speed. Was about to repeat the above process then noticed the pink wire (there are 2, a pink & white) that run from distributor to ignition coil was chaffed and bare wire was actually rubbing on the bolt that locks down the distributor. Taped over the wire and this cured the vibration. I was entirley surprised it was something this minor. just my .02 hope this helps someone.

Definitely tune up time bro. Check LTs sticky thread for suggestions.