Bullnose Enthusiasts Forum

New year same problems...all 8 injectors firing two times per revolution

Classic

List

Threaded

58 messages Options

123

Gsmblue

Re: New year same problems...all 8 injectors firing two times per revolution

Previous owner may have changed the ecu.

1985.5 F-150 XL Explorer standard cab 5.0 EFI AOD 4x4
Daily Driver. We call her Eunice the Ute.

1982 Bronco XLT Lariat 351W AOD 4x4
Code name Esperanza, or Espy to her friends. Please see my Project thread for the blow by blow.

1984 F-350 XL Centurion crew cab 460 T19 4x4
"Eylza Dual-little"

85lebaront2

Re: New year same problems...all 8 injectors firing two times per revolution

Administrator

In reply to this post by ReneH

I would suggest (based on my experience with the 1985/86 EFI systems) that you really need to take the wiring harnesses off the EFI system and check for bad sections. I have seen at least 5 of these where the insulation was actually crumbling off the wires leading to shorts. Be especially careful with any shielded wires as the inner insulation may be bad.

After 1986, the O2 sensors were changed to heated ones and relocated from the right side exhaust manifold to beyond the point where the two sides of the exhaust join.

Bill AKA "LOBO" Profile

"Getting old is inevitable, growing up is optional" Darth Vader 1986 F350 460 converted to MAF/SEFI, E4OD 12X3 1/2 rear brakes, traction loc 3:55 gear, 160 amp 3G alternator Wife's 2011 Flex Limited Daily Driver 2009 Flex Limited with factory tow package Project car 1986 Chrysler LeBaron convertible 2.2L Turbo II, modified A413

Gsmblue

Re: New year same problems...all 8 injectors firing two times per revolution

If I recall, they made a new harness. It was documented in the other thread

ReneH

Re: New year same problems...all 8 injectors firing two times per revolution

In reply to this post by 85lebaront2

Ok, you are right. There is no other thing that is possible anymore...I have changed everything except the wiring...and I have had to move it while removing the engine.

To save time, I will only re-wire the ECU.
So I have to check what material I need.
I will keep you up to date with pics, so I can show, what I understand as a perfect wiring and routing.

BTW...does anybody know where I can buy the connectors for all the sensors?

René's Profile

Bronco 1986 Ford Bronco XLT 302/347 stroker with 351W EEC-IV and 351W factory cam C6 gearbox. Jeep 1986 Jeep CJ7 256 I6 with T5 gearbox. Buggy 1972 HAZ Buggy 122 Ford Cologne V6
Baron 1994 Chrysler LeBaron convertible 183 V6 4-speed automatic

85lebaront2

Re: New year same problems...all 8 injectors firing two times per revolution

Administrator

This post was updated on .

In reply to this post by Gsmblue

They did, but from what I read, only part was redone. I was trying to find what I did with the pictures I took of the 1986 harness I sold a while back. It was in two parts, one is strictly the engine portion, the other is the body portion. The body portion goes through the oval grommet to the EEC and EEC power relay. It also connects to the fuel pump relay, solenoid bank and MAP sensor next to the battery, and has the only ground for the entire system as a two pin 1/4" flat blade plug and socket. This is an unsealed connector, attached to the bolt on the negative battery cable clamp. This is one of the problem areas on these as the battery fumes will corrode the connector to the point it has a high enough resistance that the voltages in the system are screwed up relative to ground.

If my memory is correct, the right rear intake manifold bolt has a ground wire. Several items in refreshing my memory of these systems.
(1) at the test connector (C195) there are 6 holes in it of which 3 are directly concerned with the EFI, 359 (Black with White stripe) is the sensor return to pin #46 of the 1986 EEC, 95 (Tan with Red stripe) is injector bank #2 from pin #59 of the EEC, 96 (Tan with Orange stripe) is injector bank #1. On the wiring diagrams this may be referred to as "used during vehicle assembly".
(2) next to the connector is a single Red with White stripe wire, this is called the STI for Self Test Initiate and is used to activate the EEC self test mode (this works on all the EEC-IV systems).

With the EEC removed, key on (a) fuel pumps will not run, (b) you should have power on the Tan/Orange and Tan/Red wires. Grounding Tan/Red or Tan/Orange should cause 4 of the injectors to "click", a finger on the ones on the left (driver's) side will confirm which ones Tan/Red should be only the two middle ones (cylinders 6&7), Tan/Orange should be only the two end ones (5&8). If all 4 click, your problem is definitely in the wiring.

Bill AKA "LOBO" Profile

85lebaront2

Re: New year same problems...all 8 injectors firing two times per revolution

Administrator

In reply to this post by ReneH

There is a Motorcraft connector catalog, and Rock Auto carries some, Amazon carries some and I have a few other sources (one of which is salvaged parts).

Bill AKA "LOBO" Profile

Gary Lewis

Re: New year same problems...all 8 injectors firing two times per revolution

Administrator

The catalog is at Documentation/Electrical/Connectors.

Gary, AKA "Gary fellow": Profile

Dad's: '81 F150 Ranger XLT 4x4: Down for restomod: Full-roller "stroked 351M" w/Trick Flow heads & intake, EEC-V SEFI/E4OD/3.50 gears w/Kevlar clutches
Blue: 2015 F150 Platinum 4x4 SuperCrew wearing Blue Jeans & sporting a 3.5L EB & Max Tow
Big Blue: 1985 F250HD 4x4: 460/ZF5/3.55's, D60 w/Ox locker & 10.25 Sterling/Trutrac, Blue Top & Borgeson, & EEC-V MAF/SEFI

ReneH

Re: New year same problems...all 8 injectors firing two times per revolution

In reply to this post by 85lebaront2

OK. I will check this. I have made some pictures of the status-quo:

My Self-Test-Connector...only 3 cables attached. Is the test you have mentioned possible there?

I still don't know for what this connector is...

Is this correct? All the fusible-link cables connected to battery +12V?

This is the EEC-Power-Realy, as far as I know...

For these both I haven't found a counter-part

I don't have the climate-system installed, also removed the secondary gas-pump and all EGR-parts...maybe these were for one of them...

One of the cables at the connector has no isolation...I know this is GND...but is this "common"?

I will come back here, when I have done the tests and started re-wiring.

85lebaront2

Re: New year same problems...all 8 injectors firing two times per revolution

Administrator

First picture, it looks like your wires are tan/green and tan/red for the injector control. Yes, those are the ones to ground with the EEC removed and key on.

Second picture, connector was not used, it may have have been for a not installed option. It is cheaper to build a pretty much "universal" harness.

Third picture, definitely looks correct.

Fourth picture, that appears to be the fuel pump relay as it is underhood on the driver's side. Power relay should be next to the EEC on it's mounting bracket.

Fifth and sixth pictures, again, may have never been connected, particularly the sixth due to the dirt on it.

Seventh picture, a bare wire particularly if it is braided is not abnormal in those years.

Hope these help. Unfortunately, I will be gone most of tomorrow (US Eastern time 0900-1500) so really won't be able to respond.

Bill AKA "LOBO" Profile

ReneH

Re: New year same problems...all 8 injectors firing two times per revolution

Ok. Thanks at all. I will start on Saturday by checking, respectively testing the injectors as you have mentioned.

After that, I will un-tape the harness of the ECU and set new cable to it. Independently to the test, the error can also be made by the ECU, based on wrong input data of the sensors, in my opinion. So not only caused on the output side of the ECU, maybe also effected by some inductive or capacitive wrong input...

If the harness isn't the problem...I will get mad...it's the last thing I haven't replaced...

86 1/2 Brutus

Re: New year same problems...all 8 injectors firing two times per revolution

Based on everything i read here, Gary is right it most likely is the wiring. When we restored Brutus, Nick made all new harness's for everything inside and out. You would be surprised at how much bad wire was pulled out of that truck and Nick is the original owner. I wish you good luck.

Nick and George
1986 1/2 F150 XLT Lariat 4X2 300 Six - C6 - 3:08 in a 8.8 - Fully Loaded - 8 Foot Box
Owned since new

85lebaront2

Re: New year same problems...all 8 injectors firing two times per revolution

Administrator

This post was updated on .

Let me tell you about wiring, the 1985/86 EFI trucks I have dealt with had the crappiest condition wiring I had seen since helping restore some 55-57 T-Birds. Those had the old rubber/cloth insulation, cloth would fray or rot, rubber turned to a hardness and brittleness of Bakelite. When we bought a 1955 Packard Patrician to restore (my late wife grew up with Packards) I was pleasantly surprised to find why GM snapped up Packard Wire and Cable. All wiring other than accessories was color coded and numbered with Hypalon insulation. Still fully flexible nearly 30 years later. The accessories (light sockets, blower motors etc.) were either AC Delco or Autolite and had rubber/cloth insulation that had to be handled very carefully or it crumbled.

I will not be at all surprised if the wiring is the problem.

Bill AKA "LOBO" Profile

Gary Lewis

Re: New year same problems...all 8 injectors firing two times per revolution

Administrator

Somewhere in that wiring Bank 1 and Bank 2 are shorted.

Gary, AKA "Gary fellow": Profile

86 1/2 Brutus

Re: New year same problems...all 8 injectors firing two times per revolution

In reply to this post by 85lebaront2

Yes indeed Bill, i concur, just ask Brutus. We had a double wammy , being he is a half year special edition truck, we have the joy of 86, 87, 80 and 79 wire harness

Nick and George
1986 1/2 F150 XLT Lariat 4X2 300 Six - C6 - 3:08 in a 8.8 - Fully Loaded - 8 Foot Box
Owned since new

ReneH

Re: New year same problems...all 8 injectors firing two times per revolution

In reply to this post by Gary Lewis

Hi. So I have checked again the resistance between both wires of the injector banks...what should I say... 7 ohms...so they have contact...I have done this many times without getting any resistance...so it's definitely the wiring.

Tomorrow I will open all isolation tapes and get the singe wires out. So I also get their physical route.

The one of the connectors I don't know for what it is is also directly connected to the EFI-System...same wire colors...so this connector is maybe for testing the injectors...
20230121_161401.jpg

I will keep you up to date, tomorrow when I'm starting...

85lebaront2

Re: New year same problems...all 8 injectors firing two times per revolution

Administrator

That connector may be C160, and is probably near the back of the engine. With it unplugged, and key on, you should have power at the injector wires. Grounding either one it should activate 4 injectors (either end or center).

Bill AKA "LOBO" Profile

Gary Lewis

Re: New year same problems...all 8 injectors firing two times per revolution

Administrator

In reply to this post by ReneH

Now THAT is PROGRESS!

Gary, AKA "Gary fellow": Profile

ReneH

Re: New year same problems...all 8 injectors firing two times per revolution

In reply to this post by ReneH

Ok... I have done a capital mistake...

Measuring the resistance between bank one and two will always result 7 ohms...

You ask why?

14 ohms per injector (inductor).
4 injectors parallel on one bank = 3.5 ohms per bank.

Both banks share the plus connection.
So both banks are in series if measuring from one GND to the other.
2x3.5 ohms = 7 ohms.

So this resistance is correct...that wasn't the error...

123