My truck does not want to stay running ?

[Danny_Boy]

Hello all again,
I have a 1986 Ford F-150 step side FI 5.0L V8 truck that not to long ago i bought for the wife.

Heres the thing,I start it and she runs great for anywere from 4-5 minutes and then starts to searge alittle.After a minute or two of searging it will drop way down in idel and then just die.I'll start it back up and again it will run good but only for a minute or two it does the same thing all over again just takes less time to do so.Oh and forget about putting it into gear,as soon as you do its stalls right out.

The gas tank is new and was replaced not long ago,i also noticed it has a Bosch fuel filter w/ some black wire that runs from it and goes somewere ?

Any ideas what the problem is ?

[mrltd]

The surging could be from a bad idle control solenoid. Also, bad temp sensors could cause it to run rich and surge, vacuum leaks, bad TPS....

And the "bosch fuel filter" is probably the rail mount fuel pump.

[88grandmarq]

check the ECM for trouble codes... what you describe is very consistant with a bad ISC and/or CTS sensor. Also change the T/stat if you haven't in a while.

[Danny_Boy]

Thanks for the info guys,looks like i'll just have to start replacing items untill the problem goes away.I have no way to check for codes or anything so...

Any idea were the fuel filter is on this truck ? I figured it was that Bosch unit since i seen nothing else that looked like a fuel filter.Mrltd is probaly right about it being a rail mount fuel pump.

[Blaze86Vic]

I would suggest getting it diaged. It can get very expensive very quick if you just start replacing crap.

[88grandmarq]

http://www.troublecodes.net/Ford/

If you have a test light or a analog VM, you can check codes very easily.
Most parts stores sell an inexpensive code reader too.

Don't waste your time and money, randomly replacing parts. Diagnose the problem the first.

[gadget73]

:stupid:

I'd also check the vac lines for cracks and stuff like that from sheer old age. Replacing the PCV valve, grommet and screen just for maintainence would be a good idea as well.

[monterey1962]

I will save you money right now. I once had an '86 F-150. I spent $$$ left and right before I found the solution.

Only two things you need to replace.

1. Idle Air Control Valve.

2. The second fuel filter. Yes, there is a second one. It's one of Fords bad bright ideas. '86 and '87 had 'em. There is a black canister on the inside of the frame, drivers' side, between midway back and the tanks. It has a shield over it, so look close. It is where the tank selector valve is. Depressurize the fuel system, turn the canistor open (it's a bitch), pull the filter out and throw it in the trash. DO NOT PUT A NEW FILTER IN. Put a new seal in and tighten it up. You're truck will run like new. Trust me.

If your truck has a single tank, look anyway. There should still be a second filter in the line. Let me know what you find. Might want to replace the fuel filter that is just behind the engine as well. Get a factory spec one.

[Danny_Boy]

IAC and fuel filter,sounds like two winners.

A friend i work with has something i guess that can be pluged into my truck to read for codes and such so that will be the first thing i do before i start replacing items as you all mentened

Good info monterey1962 ! I was hoping someone on here had a mid '80s Ford Truck w/ the FI 302 and maybe had the same problems and could point me in a good direction.

I'll keep ya'll posted on what i find and what cures the problem as what should be done on all maintence threads

BTW its a single gas tank.Here is a older pic i have of it,still looks the same.

[Paul_]

i dig the older style bed

i want an f-150

[monterey1962]

Oh mang, I want that truck. Those step-side boxes are getting hard to come by in good shape. Take care of it.

Here's my old boy. Part of me wishes I could have kept him, but the repair costs were running me into the ground.

[88MercWagon]

Damn Monte that thing was clean. I like your's too Danny_Boy...Flairside's are teh shit.

[Danny_Boy]

Thanks guys,i like this truck too.Im really diggin that red truck monterey1962 damn thats sharp !

I payed $500 cash for this truck and could not pass it up.Its got a rebuilt tranny with shift kit and some other performence goodies.It also has nice fog lights on the bumper too.

[Grand Marquis GT]

Monte knows how much I liked that truck. Very nice