Driving issues bucking

[hellfirejim]

I have searched but I was unable to find the answer. I have a 98 3.0 ranger auto at 217,000. While driving under lite load it will buck. For example at highway speeds and I start to go up a hill it might, might buck once maybe twice or so.

I have also noticed that it was or feels like it is down some on power. Recently we have had a very cold snap and I had to manually (foot on pedal) help the idle for about 30 seconds and then it was ok.

Finally two things. First I have changed the fuel filter and secondly it does not throw any codes even will driving. This was checked with the reader

This part is just an opinon. It feels like it is mechanically lean, not electronically lean if that makes any sense. I have a TPS the I am also going to replace. Not necesarily to cure the problem but with the miles I am sure it is worn and is pretty cheap.
Any thoughts would be appreciated.
jim

 

[almostclueless]

217K!! goodness.....have the injectors been checked/replaced?

 

[vincedia]

Not specifically our motor but I'm going to give it a shot.

http://www.focushacks.com/printable.php?modid=80

Follow the link for the temp solution to see if that is your problem. I have the same problem and I will be giving this a shot tomm.

Good luck!

Vince

 

[hellfirejim]

thanks for the input. I will try the fix to see if it makes a difference.

Apparently I forgot to add some important information, sorry. While driving around with the reader attached it showed the fuel pressure dropping. Even stranger it was more on one side of the motor.

I just don't know. It has said to me that maybe the fuel pump sock is clogged not allowing the right amount of fuel to flow. Maybe. What gets me is no codes????

any and all ideas are welcome.
jim

 

[shadetree]

The throttle position sensor will cause the symptom you are having. If you already have one, change it and see if it makes a difference. shady

 

[hellfirejim]

I have one and it is just a problem of getting it put on. Started to do that today and one screw won't come out..... My buddy has a repair shop who has done all the work on my truck. I will leave it with him and take one of his cars...

I will let you know.
jim

 

[hellfirejim]

When we disturbed the intake tract when we tried to switch TPS it changed the running of the truck. Improved, so my guess is that we are right on switching the tps. I will let you know.
jim