87 bronco EEC nightmare
Thread Starter
|
Senior User
Joined: Aug 2008
Posts: 239
Likes: 0
87 bronco EEC nightmare
some thing new happened the EEC quit giving power to the injectors, it has 40psi of gas and spark, I already removed the in tank fuel pump, how do I check the EEC, it has power according to the wiring diagram and the number on the EEC is SFI-SD3 E8SF-12A650-AA1A, it has a 5.0 and gives no check code
Lead Driver
Joined: Sep 2002
Posts: 9,182
Likes: 12
From: Gateway to the West
So, KOEO and KOER tests yield absolutely nothing? I'd be checking to make sure you haven't lost power feed to it first. KOEO and KOER tests should yield code 11 or 111 at the very least. If you can't get a code response through the KOEO test, you can check to see if there is VREF power (which is +5VDC approx.). Test by taking a voltage reading between pins 26 and 46 of the EEC computer with the computer connected, the key ON and the engine OFF. There is a litany of possible problems that need to be addressed BEFORE assuming the computer is bad. Check HERE before replacing the EEC computer.
Thread Starter
|
Senior User
Joined: Aug 2008
Posts: 239
Likes: 0
I will check that out but to top it off the fuel pump don't turn on by it self any more, the relay is good, a month ago I removed the in tank fuel pump because it was rarely getting power but the main pump would get power 75% of the time so I put in a bypass switch for when it didn't work, the EEC gots power and ground it will run on starting fluid and it is a wiring mess
Senior User
Joined: Dec 2005
Posts: 124
Likes: 0
From: Da UP, eh!
KOEO No Codes
So, KOEO and KOER tests yield absolutely nothing? I'd be checking to make sure you haven't lost power feed to it first. KOEO and KOER tests should yield code 11 or 111 at the very least. If you can't get a code response through the KOEO test, you can check to see if there is VREF power (which is +5VDC approx.). Test by taking a voltage reading between pins 26 and 46 of the EEC computer with the computer connected, the key ON and the engine OFF. There is a litany of possible problems that need to be addressed BEFORE assuming the computer is bad. Check HERE before replacing the EEC computer.
Lead Driver
Joined: Sep 2002
Posts: 9,182
Likes: 12
From: Gateway to the West
No codes at all? Does the truck start? There may be no fault codes if the truck is running right. But as this thread mentions, at the very least the ECM should give you a code 11 or 111. When the test is begun, it must be done with the engine at operating temperature. At the outset there will be a series of flashes that indicate which engine the computer in the truck is running. 2 flashes for a four-cylinder (obviously in other Ford vehicles), 3 four a 6-cylinder and four for an 8-cylinder. After that, there should be a long pause before the codes begin to flash out.
Trending Topics
Posting Guru
Joined: Nov 2004
Posts: 2,155
Likes: 1
From: sunny fla sometimes windy
Put the in tank pump back in!! It is there for a reason!! All new efi vehicles only come with an in tank and the reason is that having just the one on the frame rail can lead to
that pump cavitating and leading to poor fuel delivery to the fuel rail. The in tank gets
a steady stream of fuel to the frame rail pump so cavitation doesn't occur, which can
lead to the pump surfaces getting pitted and thereby losing efficiency and psi.
that pump cavitating and leading to poor fuel delivery to the fuel rail. The in tank gets
a steady stream of fuel to the frame rail pump so cavitation doesn't occur, which can
lead to the pump surfaces getting pitted and thereby losing efficiency and psi.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
Top 10 Fords at 2026 Carlisle Ford Nationals
Joe Kucinski
3 Best / 3 Worst Parts of Modern Ford Ownership
Brett Foote
10 Amazing Upgrades That Solve Common Ford Truck Owner Headaches
Pouria Savadkouei
Every 2026 Ford Engine Explained
Brett Foote
10 Ugly Ford Trucks That We Still Kinda Love
Joe Kucinski
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Thread Starter
|
Senior User
Joined: Aug 2008
Posts: 239
Likes: 0
with out the in tank pump it has ran better than it ever has with a steady 40psi and with how I have the return going to a filter right before the pump not the tank it can keep fuel near it, the filter has tank in, return in, out to pump
Lead Driver
Joined: Sep 2002
Posts: 9,182
Likes: 12
From: Gateway to the West
The early in-tank units were low-pressure not high pressure. They were there to keep the high pressure pump on the frame rail from starving and cavitating. The move to the in-tank high pressure units later, kept the high pressure pumps cooler during operation by leaving them submerged in fuel.
Thread
Thread Starter
Forum
Replies
Last Post
FordAnne
1987 - 1996 F150 & Larger F-Series Trucks
8
Aug 15, 2023 08:21 AM
HD
1987 - 1996 F150 & Larger F-Series Trucks
13
Jan 9, 2016 07:05 AM
