1997 Ford F150 XL 4.6L 4X4 Milage 130.000km
Problem started intermittantly at first, rough when going from45 to 55 mph. Now its everytime the veh. goes thru this transition. Can I do something?
Thanks jimmac

 

I know that it may sound far fetched....but have you checked the tire balance? I lost a wieght from one of my wheels and I would get a little vibration from about 60 to 65. Had the wheels rebalanced and all was well again.

Just a thought

 

Thanks BB69 but its only like, when you go around a corner and let off the gas then accellerate out of the corner. Once your passed the 55 mph all's OK.

 

Auto or Standard ?

 

automatic transmission

 

I've had the same issue with my 97 F150 for a few years now. The Ford dealer has been playing dumb with me. Any time I take an exit ramp from the highway and go to accellerate into the new traffic pattern it is almost like I'm running on 4 cylinders. If I let off the gas completely the truck stalls out. Otherwise, I have to get the motor up to about 2500 rpms and its like someone threw a switch and restored full power to the motor.


-David

97 F150 XLT
4.2l V6
Manual Transmission

 

David, Thanks for getting back to me, the problem is almost the same only I don't stall out. As a matter of fact after reading many many threads in this great forum on FTE. I got to the bottom of the problem and got it fixed. Now my problem is I don't know what fixed it!! Da... All at the same time I cleaned the air filter, the 02 sensor, and put in a bottle of Injector cleaner, now the problem gone. I'll have to wait for it to come back, if it does I'll do one at a time.

jimmac

 

I began to get the same problem as described above very recently without the stalling. The engine spudders (like it is starved for air or fuel) when I accelarate in high gears. I can jackrabbit out of stops with no problems. I have a 2002 F-150 V6.

So far I have...
-changed the fuel filter
-changed the air filter
-cleaned the butterfly intake
-began using highest octane fuel
-checked my spark plug wires
-used "water out" and fuel injector cleaner

All to no avail.

Any advice would be deeply appreciated.

Jimmac, did you clean or replace the oxygen sensor? How did you do it?

Thanks, Scott

 

Scott, I'm by no means an expert on this stuff. The sensor I cleaned is inline with the air filter on my truck, a 1997 it wasn't dirty but I cleaned it anyway, yours is probably diff. I would suggest you read Racerguy's threads, His FAQ's start here is very informative. Good Luck.

jimmac

 

Scott, it could be a problem with your oxygen sensor, but they cannot be cleaned. Before you invest in new o2 sensors, go to Autozone and have them scan for codes, to be sure this is the problem. Other than the O2 sensor, it would probably be one of the other sensors, but until you get the codes, it's difficult to find which one.

Running high octane fuel will not solve the problem, as the engine was designed to run on 87 octane fuel.

 

What was the outcome of this? My truck just started doing something similar.

 

Chuck, these threads are 8 to 10 years old, have you noticed?
Your problem is a faulty coil.
If you had done more research you would have come across the answer.
.
Here it is in short.
You have a coil with shorted turns that is not a hard fault. This why there is no code set.
How to find it without guessing and spending a lot of money on parts you don't need:
Have a Scanner used to look at live data.
Look at mode 6, test 53.
This test looks at all cylinder monitors.
The one with high counts, out of limits, is the problem.
Another way is to set the Scanner up to trap the fault when it happens and freeze frame the information showing the cylinder that is causing the problem.
The faulty coil will not set a code for you to easily see.
You cannot guess on these systems without getting lucky.
Good luck.

 

Thanks but what are "shorted turns"? Like what are "turns"?

 

What is a coil?
A form wound with wire.
Many turns around the form.
The turns must be insulated from each other.
If any turns are electrically 'shorted' to each other in that winding, the coil output voltage will reduce.
This will cause misfires under certain conditions.
This condition can also be temperature sensitive and intermittent from the wide variations in temperature on the engine and in the engine bay plus outside temperature changes.
The faulty coil will be seen with a Scanner looking at the misfire monitors as first explained.
Good luck..
.

 

Understood. Thanks.