I'll try not to post an entire book.. But I bought a 2000 F250 not even 8 months ago, it did have issues before but I changed out the spark plugs and coils and it fixed it's original missing issues.. I also just recently changed the fuel filter but it didn't fix it's new problem.. It drives ok around town but if I get over 35 mph it doesn't run well... If I try to keep a steady foot on the gas but don't get the Rpm's over 2000, the Rpm's will stay where they're at for just a second then they will drop down and the whole truck starts shaking.. I push more on the gas and it shakes even more and the Rpm's don't move at all until I really step on it.. It lacks in power going up hills as well... The dealership i bought it from said the Catalytic Converter was bad but my uncle who is a mechanic says it isn't.. Anyone have any ideas? I'd appreciate anything.. It's the first vehicle I've bought so kinda wanna make it last..

 

Could be the catalytic converter. I would have someone else look at it.

 

Clogged exhaust or too low fuel pressure for sure.

 

Why does uncle dispute clogged cat theory. Sure sounds as though that could be the culprit. Might also check for vacuum leaks?

 

Connect a vacuum gauge to intake manifold and confirm or eliminate a restricted exhaust in about 30 seconds. There's no reason to guess or argue about it.

 

Would a bad cat cause it to start poorly

 

Well now.. It's even worse.. First started it up for work cause it was frosty outside.. And alot of white smoke was coming out the exhaust and by the time I got to work which Inst even a 4 minute drive my temperature was all the way up and my engine light was on.. Then Later that day I got home and went to put coolant in it cause there wasn't any before.. Then I open it up and theres crap in there like it filled back up..

 

What did you think was going to happen? Don't guess, determine what the fault is, and repair it. Don't let a $35 problem turn into a $350 or even a $3500 problem.

 

My dad, uncle and grandpa believe it's a bad head and gasket.. So getting that and hoping to fix the issue

 

Well that settles it then!

 

Good luck check the heads and make sure to check everything is square, the heads the exhaust ports etc ... also it maybe worth it to timesert the heads for better piece of mind.

 

Personally if it was the heads, I would be lead to believe you would have more issues than what your having now.

I personally say check the cat aswell. Could be a bad egr aswell.