Computer Problem
Thread Starter
|
Freshman User
Joined: Feb 2009
Posts: 26
Likes: 0
Computer Problem
I have a 87 fuel injected 300, the truck has set for about 5 years. I drained the gas, replaced the high presssure pump, plugs, engine module, fuel pump relay and removed both of the cats and the muffler. The truck starts fine , but will only fun for about 5 minutes, then it will die. If you let is cool off for a little bit then it will start right up. I have replaced about everything i know to replace, but the computer, some one told me that it could be the propblem but i was trying to get some more thoughts on the subject before i go and buy anymore usless parts. Thanks for the help.
Elder User
Joined: Feb 2002
Posts: 504
Likes: 2
From: Saddle Brook United State
Sounds like you might have an TFI ignition module (the one on the distributor) problem. That is if the 87 has a distributor mounted TFI module. Those are the symptoms of a bad one. When it dies check for spark. Also you need to check for fuel pressure on the fuel rail, for that you will need a gauge assembly , about $10.
Thread Starter
|
Freshman User
Joined: Feb 2009
Posts: 26
Likes: 0
I replaced the ignition module, that was what i thought it was. when it dies the fuel pressure drops to zero, so i replaced the high pressure pump and the fuel relay. Do you think it could be the low pressure pump.
Elder User
Joined: Feb 2002
Posts: 504
Likes: 2
From: Saddle Brook United State
I would start with the pressure regulator on the fuel rail and change that first. I am going by mine (90) and that has only one pump and a pressure regulator on the fuel rail. The low pressure (in tank) pump is a boost pump for the high pressure pump. It supplies it with pressurized fuel so it doesn't have to work as hard. I would guess if it (low pressure pump) was bad the high pressure pump would have a hard time pulling fuel through a bad pump due to the internal design of the pumps. There is a test for the low pressure pump in one of my books , but it gets involved. I would run the engine with the pressure test gauge on the fuel rail and watch to see what happens. Does it loose pressure all of a sudden or gradually? First I would change the fuel pressure regulator.
Thread Starter
|
Freshman User
Joined: Feb 2009
Posts: 26
Likes: 0
I replaced the fuel pressure regulator, and now i can drive it with out it shutting off. But, instead of cutting all the way off it shudders and acts like i'm running out of gas when i'm going up hil or the motor gets a load on it. I put a fresh fuel filter on it, but it didn't help. Any ideas, Thanks for the help.
Elder User
Joined: Feb 2002
Posts: 504
Likes: 2
From: Saddle Brook United State
Did you replace the fuel filter after all that time it may be clogged with sludge from old gas? Mine is on the frame about mid way. Never mind I see you did.
Trending Topics
Posting Guru
Joined: Sep 2004
Posts: 1,915
Likes: 1
From: Yokosuka, Honshu, Japan
May want to take a look at your stator and pickup inside the distributor. If they are dirty, wet, or going out, it will cause all kinds of issues and mimick a bad TFI module somewhat. If you haven't looked at the cap, rotor, wires, and plugs, you may want to check them as well. If you have a code reader - pull codes. You can also go to most parts stores and they can loan you a reader to pull codes or pull them for you for free. The only other thing I can think of, in relation to the FPR, is maybe the MAP sensor or EGR is having issues.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Top 10 Ford Truck Tragedies
Joe Kucinski
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Posting Guru
Joined: May 2007
Posts: 1,208
Likes: 2
From: North Reading Mass
My 94 had the same issue before it finally died. The problem was in the wire harness that fed the pump above the tank. A bad pump can be intermittent but many times its the wiring. My system is the single pump one. Unfortunately many of the auto parts stores will only read codes for OBD2. The OBD1 system on your truck can be read without a code reader from info on this and other sites.
regards
rikard
regards
rikard
Thread Starter
|
Freshman User
Joined: Feb 2009
Posts: 26
Likes: 0
i replaced the in tank pump, and inspected all the wiring. Now that i did this and replaced the regulater, it doesent die all the way. When im driving along and put it in fourth and start gion up a hill it seems to be flooding or running out of gas, hard to tell witch. I have plenty of gas in the tank.
I have replaced everything in the fuel system except the injecters. The propblem is a lot better but still there. I'm out of ideas of what to do.
I have replaced everything in the fuel system except the injecters. The propblem is a lot better but still there. I'm out of ideas of what to do.
Elder User
Joined: Feb 2002
Posts: 504
Likes: 2
From: Saddle Brook United State
You might want to find out exactly what the EGR code is/means. If you have an egr valve stuck open it could impact power when you need it. The thermactor (whatever it said) is part of the air system ( read emissions) that feed air to the ports in the head at the exhaust ports and feeds air to the cat/cats.