River trail farms
I am having the exact same problem with the MAF causing engine misfires and I have yet to diagnose it... Mine only does it when its uner high stress (going 65 mph on the highway or going up a steeper incline) If i get any insite I will share it.

 

WOW!! talk about consecutive posting.

next time, just use the "edit" feature found along the bottom of your post, and fix/add to what you said.

 

Actually I looked up on the net about malfunctioning MAF's and I came across this GMC site http://www.niehoff.com/techtips/15premass.html that said that a TPS can throw false codes and usually the cause of Multiple MAF sensor failure problems. However we changed the TPS tonight and it solved the problem for now. It runs great so far! The SES light went off and is fine, as far as the Distributor cap me and my son took a tie and tightened it down for now until I get the money to fix it. But you are right about getting it fixed, that will the next thing that we get taken care of.

I changed the TPS sensor tonight and it fixed mine for now, hopefully for good! Heres the site I found, check it out. http://www.niehoff.com/techtips/15premass.html I pulled in a parking area today and it just died before I replaced the TPS and the SES light went out and the RPMs at idling was bouncing around and my son looked at that an thought like me that it was the TPS and when we changed it so far it has been ok since I came home and it drove great.....

 

Well, for your sake, I hope that cures your problem. But you still did not diagnose a thing... You never mentioned a backfire which would have been VERY noticeable.. I doubt that you ever needed to replace the MAF sensor. The link you posted probably does not apply at all in your case. You could have tested the TPS sensor to determine if it was the problem.

 

Replaced the TPS and it is doing fine so far, I found the info about MAF repeated failure, on this site,http://www.niehoff.com/techtips/15premass.html so I called a Ramey's Service guy that I know and he suggested the same the TPS, hope that this info helps others having the same problems. As for the distributer cap we tied it down tight until I can get it fixed properly, I guess I will have to replace the whole distributer eventually where the ear is broken. Anyway I hoped this helped.. Thanks for all your input.

The car never backfired but one time and thats when the mechanic had it, it had never done that to me. However I would have had to taken it to Ramey's or somewere like that to have it diagnosed, or like you said tested the TPS, also how do you test the TPS? However I was sitting in the car yesterday and the rpm guage was jumping when it was idling which was erratic, and just a shot in the dark we bought the tps and changed it and it worked. Running excellent so far!