2001 Ranger 4.0 Problems

[Zack4831]

Hi folks. This is my first post, sorta. Computer took a dump and destroyed all my passwords and user names so I rejoined.
I've got a problem with my 2001 Ford Ranger XLT 4.0 engine. Runs fine in cooler weather but on a hot day the engine starts to shut down., no acceleration. If I pull off the road, turn the engine off for a few minutes then restart it all is good; for 5 miles or so. Then it starts all over, surging and loss of power. The idle is not affected. Just when I try to accelerate.

Put a code reader on it and no codes. Thought it might be the fuel filter, changed that out, installed a new MAF sensor on and that didn't fix it.
Have any of guys ever ran across a problem like this? Again, just on hot days. If the outside temp is 60F or below, engine runs like a dream.

Is it possible this could be a fuel pump going bad? Possible that the warmer days affect the pump in some way? This problem showed up late last summer, then it cooled down. All winter truck ran fine. Now with the return of warm weather the problem's back.
Thanks in advance. Any help you can give me is much appreciated! Zack

 

[SenorNoob]

On an 01, do you have a scanner that can view live data?

If so the first thing I'd check is engine temperature when it does it. This feels like the computer thinks it's hotter than it really is...

 

[Zack4831]

Thanks SenorNoob, I'll check it out. YES, I do have a scanner that can view live data. Bought one for this project.

I've been reading about Ford's 'limp mode'. Was limp mode a thing back in 2001? When did they start doing that? Thanks for your reply. Zack

 

[lil_Blue_Ford]

Yeah, I’d take a good look at live data. Before, during and after it does it. Something is reacting badly to heat. On the old trucks that was usually the TFI module but that doesn’t apply to you exactly. The 4.0 never used those.

 

[SenorNoob]

Limp mode has been a thing on EFI since at least the late 80s. Always gotta have some kind of plan if a sensor goes out.

 

[Zack4831]

Well, I think I'm getting somewhere. That live stream code reader is SO much better than what I had/have. There is a learning curve to it.
55F here so of course the Ranger motor runs like a dream. The problem waits till hot weather to rear its ugly head.
BUT, I did drive it to town today, ran it hard and, when I got home and before I shut the motor off I plugged in the new live stream code reader and it showed a 'pending' P0455 code, which says:

Evaporative Emission Control System Leak Detected (gross leak).

What'll happen I think, is that after the motor cools down the pending P0455 code will go away. What goes bad on the EVAP system that might be causing this problem? Any insight is surely appreciated. Zack

PS, SenorNoob, that makes sense, EVAP system had a bad gross leak and is going into 'limp' mode to protect the engine. The hotter the ambient air temp the more pronounced the problem, finally getting drastic enough that the computer limits the rpm to protect the engine. Does that sound right to you?