My 1993 Ford Bronco seems to start running rough when I'm pulling a tailer.
It will run fine for about 30mi. or till it gets hot.

Thanks, Matt

 

Try a search and if you can't find your problem at least you will have a better idea
on how to explain the problems you are having.

 

Welcome to FTE and a great group of helpful folks.

First I would suggest you pull codes. Mouse over Forums above and click on Search. Add the "+" to include both search words like +pull +codes. Another trick is to hold down Ctrl and click both the Bronco and F-150 to search both forums at the sime time. You can pull codes with a paper clip but I prefer the thirty something dollad digital code reader. If you get code 111, indicating pass then go with copper Motorcraft or Autolite plugs and 9mm Ford Racing wires while you are at it. Set timing at 11-12 degrees btdc.

How hot is it getting? It it overheating?

I pull a trailer 90% of the time. When mine started missing and gas mileage got horrible the above fixed it.

 

b4hntn,,is right....fixed mine too....be sure and run the wires the way the sticker (where the vacuum,epa and jack instructions are...) says or you'll have mis fires...go ahead and get a rotor and dist cap too...
Capt.G

 

I have replaced the plugs and wires a few mouth ago.
I didn't however replace them with what you suggested. I have also replaced the rotor and cap.
Could this be the cat. backing up when it gets hot under a load.
Or mabey the O2 senors.
No it is not over heating.
I'm have someone that has a digtel code read. Hopefuly that will happen this week.
Thanks for the info.

 

Please enter info into a signature so we do not need to ask year, engine, etc. I make it more convenient. Triple check your plug wire hookup.

Look at 7 and 8 wires for possible cross firing. Also, you might check it on a night with high humidity to see any arcing.

What about the fuel filter? Could it be starving for gas under load?

 

He can't add info to his signature yet you need so many posts, For now just put a tag line at the bottom of your posts in the future. The cat should do better when it is hot
Is this a daily driver or just a weekend toy hauler? You can clean the O2 sensor before
replacing it if the code scan comes back with bad O2. If you do short runs less than
20 minutes on a regular basis(work, school) or if it is just a weekend truck. Condensation and carbon could be building up in all your systems and would benifit
from a weekly highway jaunt for an extended time say if normal drive is 20 minutes
at 55mph get it out on the highway at 70mph for an hour and go up to 80 then 75
basically get it to really get everything heated up good to blow all the garbage out.
O2 and cat con will self clean if brought to the right temp for long enough. To make
sure the O2 is clean take out and run through a propane torch flame for 20 seconds
and wipe with a lint free cloth, If it has a buildup of carbon it may take longer just
add 7-10 sec wipe clean until the layers of carbon are thinned out, It is not going to
come out sparkling new. You just need it to get thin so it can have better response
time to get the ratio right. When is the last time the trans fluid was changed? When
towing you need to change out the fluid more frequently!!

 

I will check the wires and the fuel filter.
This is a daily driver 10 to 20 miles a day.
When this problem happen I had been driving about 30 to 40 miles at 50 to 60 mph towing a trailer loaded with wood. ( not a big load )
This has happed before but not as bad when I frist bought the bronco it was about a 30 mile trip.
This was only the second time I have towed something more then 5 miles.
The tran fuild was change about 10,000 to 15,000 miles ago.

Not sure how to do a signature. I'm new at this.
1993 Bronco 302 5sp.
Thanks,

 

You need to get out and run it for an hour and half or two hours straight running to
get everything up to temp!! Daily10-20-30 mile runs are not good since things do not get hot enough to burn of C&C!! Try a nice blast down the highway at 70 mph or so
and just drive around for awhile varying speeds end with another quick blast, I would pull the plugs before and after and see what they look like. http://www.ngksparkplugs.com/techinf...q/faqread2.asp