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F-150 Engine Problems.

Greetings!
This is my first post, not likely to be my last.
This is about my first Ford, I just got the truck off of my Grandpa, needed something to run to work and back in.
First off, it's an 86 F-150 with a 302 V8 FI, Engine has about 200k or more on it, no way of knowing since the engine was rebuilt or something sometime ago. (Details are kind of hard to get.)
I've several problems, I'm going to start with the one that concerns me the most.
Now keep in mind, I don't hot-rod my truck, can't afford the gas, and as a Professional Driver (Semi) I can't afford the ticket.
The issue is, when I press on the gas pedal, I have to use a feather touch, if I were to try to get a quick start, or hot-rod the engine, it bogs down and sputters pretty hard. Getting up to speed takes a little more time, but it will run pretty good once it gets to point.
Also with this, the truck has issues with hills, I can keep the same amount of pressure on the pedal, but once I come up to a hill, I will drop speed quickly. (IE: 65 down to 55)

Any help in fixing this is greatly appreciated, and as I'm on a tight budget right now, results that require money will be slow in coming. (The joys of the first paycheck.)

Thank you.
 

mtflat

Flatheads Forever
2,559
147
Welcome!
Automatic? I have the same truck, but with a manual trans.

A code reader would help - certainly shorten the process of eliminating things that are working. Things I'd check and replace or maintain as you can:

Cheap fix. Take the throttle body off and clean out the carbon that builds up there. It bolts to the front of the intake plenum.

And/or run a bottle of Seafoam treatment thru it. 1/3 bottle in the crankcase, 1/3 in the fuel tank and dump the last 1/3 down the vacuum hose on the brake booster. Let sit for 20 minutes and start it up. Smokes like a house on fire and stinks!

Throttle Positioning Sensor could be bad.

EGR body and O2 Sensor could throw things off.

Could be odd things like a fuel pressure regulator starting to go or fuel pumps (low-pressure in the tank and hi-pressure pump inside the frame rail under the driver's door) or etc...........

I had a 302 I recently replaced that I believed was shot. When I pulled it I realized it had a badly worn timing chain/gears. Wear to the cylinders wasn't bad enough to cause the poor running condition it had.

Keep in touch. I happen to love the 5.0L EFI. My truck has logged 330,000 miles.
 
Thanks for the info. I'll do that as soon as I can, as for cleaning the throttle body, Got a picture of what it's supposed to look like?
Most of my experinces are with older cars/trucks with a carb. This FI stuff throws me through a loop.
First paycheck, I'll pickup a code reader. As for TPS, EGR, Not quite sure what those are exactly either.
As for the fuel pumps, those will be the first to be replaced, along with the Oil Pan Gasket, which has a pretty good leak.

Since you have the same truck, I'll ask this, although I'm pretty sure I know the answer, my lights, the ones inside the truck, below the passenger side dash, and the dome light, do not work unless the radio is turned on. Is this a wiring issue from Ford Factory, or is something within my truck crossed? (I'm guessing the Latter, but the very few Fords I've worked on, oil changes and etc were not designed, smart, I will say.)
 
Why are you going to replace the Fuel Pumps?
AS far as codes go you do not need a code reader how ever they are nice.

To check your codes without a reder go to one of these links below:

This is good for the KOEO test:
http://fordfuelinjection.com/?p=13

This one is good for the KOER test:
http://www.broncodata.com/tech/codes.htm

Throttle Body:
ThrottleBody.jpg


EGR
EGRVan.jpg


TPS
TPS.jpg

/
 
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Thanks for the picture, I'll get out there tomorrow (Depending on the weather.) And take a look at it. It'll have to be next weekend before I can actually dismantle anything as I need the truck to get to work. (That and I'll need to make sure I have money to replace anything that might go wrong, Murphy's Law)
As for the Code Reader, I've been working on cars/trucks for a few years now, simple things, IE: Starter, Alternator, Water Pump, etc. It's just about time that I learn how to use one.
In regards of the pumps, the truck had been sitting for quite some time, at least three or four months out at my grandpa's house, and no telling how long it's been since the truck was driven before that. So since I need to replace the fuel level sensor on the rear tank, I might as well replace the filters and the pumps while I'm working on it. (Depending on the difficultly level I might just replace the fuel line completely, make sure anything that's built up in there won't effect me later down the line.)
 
Alright, I went out and looked at the engine and I found it. So when I take this off, what do I use to clean it? I don't want to use something that might cause problems. Can't remember the name of it, but I used to use this brake cleaner, came in a red can and a green can, fast drying, no residue stuff. (Brakekleen? Something.) Would that work in cleaning off the Throttle Body?
 

john112deere

caffeine junkie
Staff member
10,807
405
central Vermont
They make spray cans of throttle body cleaner.

I'd say get a can of one of them...other stuff may work, but for the $3/can, I'd just as soon use the right stuff for the job.
 
True enough for that. Alright, I'll bookmark this, and as soon as I can get the money to start this, I'll update. Even though this is just a start, I want to say thank you all for the help.
 

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