Hey guys

I have a 1998 F150 4.6 2wd regular cab with 255,000 miles on it. Lately it has had some problems. The first is that it will run really rough when under a load, meaning when I step on the gas. It runs smooth at idle and at cruise but when I step on the accelerator it bogs way down and almost shuts off. I have changed the spark plugs, spark plug wires, coil packs and fuel filter. Now I'm thinking maybe fuel pump? Any suggestions??

The other issue is that when the truck is having to work a little harder (i.e. pulling a trailer or running in the summer with the AC on) it will start to run hot. I have changed the thermostat, flushed the coolant, cleaned out the radiator, etc. and it still does it.

Could both of my issues be related to a fuel problem??

Thanks in advance guys

 

yep... get that fuel pressure tested.
Cycle the key on and off a few times when testing the fuel pressure...watch to see if the pressure slowly rises.

but on a simpler note.... did ya ever change the air filter?

 

When you"re checking/changing your air filter
clean the mass air flow sensor as well
Good luck keep us posted

 

Oh yeah...forgot to mention that.

 

hey guys how do you CLEAN the mass air flow sensor "properly" i know its a silly question but can you use a spray cleaner of some sort

thanks

 

I prefer to use aerosol cleaners that state on the container that it is safe for MAF sensors. I know of others that just use carb cleaner. but I'd stay with cleaner for MAF sensors....most parts stores carry this.

How to clean the MAF (Mass Airflow Sensor) in a Ford F150

Part 1 -How to Clean the MAF Sensor (Ford 4.2L, 4.6L, 5.4L).

 

I'd double check your plugs and wires to ensure they're seated properly.

 

Alright, so I got the coil packs and plugs (auto lite platinums) tested. Everything was good. Fuel pressure tested good as well. My number 4 plug wire was popping off, so I took a pair of pliers and crimped it down slightly. I also cleaned my mass air flow censor. What a difference that made! I took mine all the way out before cleaning it but probably could have just cleaned it without taking it out. Simple and cheap fix but made a big difference. Time will tell if it cures my other problem of overheating when under a load, but it sure made it run smoother. Thanks for the help guys.

 

I just wanted to ask a quick question. I have heard before that you cant clean the mass air flow sensors while the engines warm or has been ran. I have heard the engine has to have been sitting for several hours before you can clean it. Is this true ? I don't mean to ask this on your thread but I would really like to know so I can clean mine very soon

 

IDK blue,I have never heard of that before
There is a small heated element that might be a problem but should cool rather quickly
I have cleaned them right after a hesitation diagnoses and have never had a problem
Maybe someone else will chime in