Wondering if someone could give me some assistance. I have a 1997 Blazer 4X4, 4.3 188,000 miles. About a week ago it had been raining and I was leaving. Took off and Blazer started running rough and missing. A few seconds later, it cleared up and did fine until last night. It was raining and I drove a few miles don the road. It started missing badly again. I pulled over and it died. After trying a few times it started up and ran rough but got me home. This morning I tried to start it. It turns over and tries to start but doesnt. Trying to get some ideas. Could moisture be getting in something? Both times I had filled up with gas the night before. Don't really want to have it towed to a shop.

 

Sounds pretty much like a crack in your distributor cap.
Replace your cap and rotor and you'll be fine.
Maybe a good time to check/replace the wires/sparkplugs as well.

 

I agree about the distributor. Make sure that there is no moisture anywhere under the cap. Might take a hairdryer to it, if you can.

 

There are a few possibilities. I have seen water in fuel cause issues like this which is something that a few bottles of IsoHeat can help work through. It is also possible that the EGR valve has stuck open, causing exhaust gases to be metered, uncontrollably, back into the intake, displacing combustion supporting oxygen. Then there is the possibility that the pump is not supplying enough fuel pressure to allow the vehicle to run appropriately. Plus more, somewhat less likely causes.

 

Think I will start with the distributor cap and if no luck there, might have to take it in. Just wondering, how tough they are to replace. Not real familiar with the newer vehicles. I have looked at it, looks like it may be difficult to get to. Thanks for the replies.

 

Heres an update. Replaced distributor cap and button, which was easy enough. Had one plug wire that was burnt at the distributor cap. So I replaced the wires, will do plugs tomorrow(if I can). It then started up. Took it for a 5 mile test drive and it seems to do great. I will try it tomorrow. It is suppose to rain all day. I was wondering also, how big of a job is it to change the plugs. The back ones look like it would be a job. Thanks for all the help!

 

Hope your problem is solved. It will make it easierif youremove the wheels and go in through the wheelwells to change the plugs.