Bought a 2000 ford super crew a few months ago. lately iv been having a few problems. i hope someone can help? It has a 5.4 auto . the issue . when driving in town runs good.but on the highway. When you downshift to pass it dont accelerate . and revs up to 3000 rpm. W hen you let off a little it picks back up and will go .last but not least no codes ... CAN ANYONE HELP.

 

I had similar symptoms. However I was getting P0701 and P0704 codes after a while. I replaced the PCV hose and valve, the evap hose (it was pretty toasted), the small vacuum line connections (where they connect to the plastic T connections. Also in bad shape) and a new fuel filter. It's running great now. Not sure which was the magic fix but it is fixed. Cleared the codes and it's been good since. That was a couple of months ago.

You can see what my vac line connections looked like in here. https://www.f150forum.com/f6/what-ho...estion-334355/

 

Thank you .For the info, I will start there. First ford I've owned so kinda lost. Learning new things every. Day Thanks again for you help

 

During my research, I was finding a lot of the suggestions to start with the PCV valve and hose (They come together). I bought OEM from the dealer and it wasn't too expensive. I started there and started replacing the other stuff after I noticed they looked pretty bad. The fuel filter was for good measure as I had not changed that in a very long time.

However, this is what worked for me and I can't say it will fix yours. Before you run out and start buying parts, see if other more experienced members respond and offer suggestions.

 

It should set a hard code, if it did that. Have you had the OBDII computer checked for any stored codes? This might help narrow it down. I think it is best to start there, then work from that point. Hopefully there is a code set to try and follow.

 

This is really good maintenance on your truck to keep it running great and it is well worth the little bit of money it costs. You could also clean your MAF because this is also both cheap and easy to do (spray it down with MAF cleaner) and will make sure your truck continues to run good. Check the air filter when you do this. Running a bottle of fuel system cleaner through your next tank of gas is also cheap and cleans up the injectors.