Hello all still new here but have lurked for a short while and like the answers and the questions. Now for my problems. bought the 350 about three years ago to use as a woods truck and to plow the drive. has always stumbled at low idle. On thanksgiving coming out of the woods the engine started to surge up and down did make it back to the house but the truck was not happy. started playing with vacuum lines and unplugged most of them found out the charcoal canister was only hooked to rusted metal and the same with the air pump. I am not concerned with emission things as it will never go on the road. But I need to get it running. Back to the story I had it idling nice and would rev up and sound good so back in the woods on Saturday. Drove in ok everything is downhill from the house, but when it was time to come home with a load of wood it would not climb the hill it would almost die out when you put it in gear and try to accelerate. It lived in the woods for a couple of weeks while I tried everything. Finally a friend helped haul it back to the house without the wood. I have found some of the problem with the map sensor when I pulled the airline off it idled a lot better. But still no power. And I pulled the cataylic converter off, just made it louder did poke a hole down through it hoping it would help. Any and all thoughts would be appreciated.
thanks for reading my saga

Fred in Connecticut

 

Temporarily plug all those vacuum leaks, no matter where they went, then you are going to have to start re-constructing the components they went to, unfortunately you need all the emissions controls to be working on these EFI computerized trucks.
J-yards are your best friend when it comes to scavenging old emiss. parts.
Hope this helps, and welcome to the zone!

 

Hi fredinct (good abbreviation) and you are in for a treat. I had a little stalling on this 460ci warm motor when in reverse that would surge and sometimes kill the engine. Ran wonderful except for that. i spent hours trouble-shooting and getting advice here. There are more friggin' vacuum lines and units on our motor than you can shake a can of worms at. And they all have to work. So get your favorite leak detector method, a stethoscope helps too, replace any brittle or cracked lines. Bend the lines a little and if fine cracks show up replace it. Work systematically from the top and down on all sides, in the back where you can't see, have to go by feel. And those lines go everywhere. Sounds like you've got missing lines and units to make it hard to replace and reroute them. My Haynes book shows just the major units like EGR and some emissions control lines.

There might be a vacuum schematic around here. Could you list more specs on your truck/engine/transmission to give a firmer picture of what you're working on?

 

thanks for the responses, I was hoping to eliminate a lot of the emission stuff, but may have to rebuild most of it. also have a leaking oil pan could be the result of the converter being possible plugged. I did take it off, just made it louder and did not improve the running. But did run a crowbar through it to open it up more. I know the lines off the air pump are rotted and the line from the gas tank to the charcoal canister is shot also. do you think all that needs to be replaced to hope to get it running again?

 

Unfortunately the coffee can has to be hooked up and working, the EGR relies on it.

Ran a crowbar through what?
You've got a good truck, but... Winter is a good time for some TLC, indoors i hope.

Here's a couple of basic vacuum schematics, they don't tell the whole story but might be enough

5.8L in a '95 F150
#ad


5.8L in a '95 Bronco
#ad

 

I poked a hole through the catalytic converter, to let more pressure out, as I said when I removed it the engine ran the same but I will try anything once. and this is my woods truck and I plow the driveway so it scares me if it snows heavy before it gets fixed. but I do have a friend who would push most of the drive for me, for a fee. I will try to pressure test the fuel pump this week end to make sure it is not the fuel pump. I am at the stage where anything will be tried.

 

I'm going to agree with the group here. You need to have all vacuum lines hooked up. If they're cracked, split, or anything else that might cause a leak, replace them. It's difficult enough to troubleshoot engine problems, but if there's a vacuum leak involved in one or more hoses, you'll never figure out what the problem is until the vacuum leaks are taken out of the equation.

 

thanks for the replies I have not had a chance to dig into the issue between the snow and the cold. I still need to check the fuel pressure I borrowed a tester but need to pickup an adapter to connect the gauge will get to it soon. shoveled snow fro three hours this past weekend. but keep the thoughts coming. thanks again.

 

Start with the map sensor up there on the firewall on the passenger side above the heater. be sure the electrical connection is hooked up too.
It will NOT run without that

 

thanks for the reply, the map sensor is one of the troubles, playing with the vacuum lines plugging it into the map made the truck stall, unplugging the vacuum the truck would idle. pulling the plug on the map without the vacuum line made on difference.
one of the mechanics I talk with said unplugging the power plug would put it into a fail safe mode and it should run.

 

It will run, but will be in "limp mode"
That is the mode that is there to get you to the repair shop when there is a code out problem. Sometimes Limp mode is only temporary, and may quit when you are in a very bad place to be


I wouldn't want to pay for the gas to run that truck!
Keep in mind, that running raw fuel down into the cat will overheat it, and cause it to melt down, creating another complete set of troubles for you

I have a 92 5.8 that I can take a picture of, and post a vacuum diagram for you if you want
Keep in mind, that every sensor, and vacuum componet was put on there to do a job to make the engine run properly
A lot of people think that unhooking "stuff" makes it run better, but that is far from the truth. The computer needs signals to know what is going on, and needs to tell the components what to do

 

thanks for the reply, I know it would run great with everything working on it but for gas mileage it may run 40 miles in a year it is about one half a mile down to the woods area and a half mile home with about a half a cord of wood I cut at the most 8 cord a year and then it plows my 500 foot driveway four or five times a year. it does not leave the farm. yes I would like it to run perfect maybe over the summer I can replace most of the emmissions stuff but in the cold and the snow I am willing to cut corners. most of the wood is in the yard it is the plowing that is important. it is suppose to warm up a little this week so am shotting to get the gas pressure tested to see if the fuel pump is running correctly. and will work from there to try to limp through the winter. but I really do appreciate the help and advice. thank you very much.
fred

 

I would like to appologize to everyone when I reread my previous post I sounded shi**y I am sorry. I have been frustrated trying to get my old stuff to run correctly. when I am not a great diagnostic type mechanic. I can rip out and replace a lot but that only helps if you know what is wrong. please accept my remorse.
thanks
Fred