'92 Shuddering Power Loss...

Little background on the vechile... I bought the '92 3.1 liter LS 4x4 mid last year because I liked the look of it. The guy said he replaced the radiator and he only owned it a year. Its got about 165K on it and the engine doesn't really leak anything. I'm having two issues with this truck right now...

In Feburary I went to my brothers(about 3 hours one way). On the way back I hit a big snow storm and taking a guess that snow got up inside the grill more then likely. But on that trip the check trans fluid light came on. So I stopped and not knowing where to put it because they didn't label any freakin' thing I put it in something else. That didn't matter, but I kept driving it even though it was probably low on tranny fluid. It shudders, like actually shakes. Not a constant thing, but it'll shake for maybe 3-4 minutes and stop then 40 miles down the road do it again. It was doing this until recently. And I did add tranny fluid up to par. It gradually did this more and worse. For awhile if I put it in 3rd gear it would stop, but that quick fix stopped working. It would only do it at low RPM's and when I started hitting 45-75.

Now the problem is it stopped doing that when I was on the highway and now its just lost all its power. I have to floor it to move it. It basically takes me about 5 minutes to get to 50 where it tops out at. It slows way down going up hills. But it doesn't shudder anymore. It does seem to idle a bit weirder then usual.

So I'm not sure what to think... I've done the gas liner cleaner and injector cleaner. People say it may be the fuel injector is shot, the c. convertor might have collapsed making "stuffed" exhaust. I read one post it might be a vaccum attachment???

PLEASE PLEASE let me know... I need a stabile running vechile so I can make the 3 hour trip to my brothers because hes getting married this year...


Also the other minor things... Anyone know why the Check Engine light comes on? whenever its on or about to, it interfers with my cruise control. Also my back passenger door doesn't want to open anymore, from the inside or out. So its not the child-proof door thing... I can't even get it open to look at the locking mechanism...

I'd appreciate any and all help or pointers or thoughts or anything...

Joe

Thanks for all the help guys, I appreciate it.....