Bullnose Enthusiasts Forum

"The Great Unscrewing"

Classic

List

Threaded

63 messages Options

1234

Gary Lewis

Re: "The Great Unscrewing"

Administrator

Yes, the 1985 EFI system only has one O2 sensor. The one shown below:

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

railwayboiii

Re: "The Great Unscrewing"

The "Unscrewing" continues...

My new solenoid cluster came in with attached vacuum lines in tow. Upon a slight brushing of the lines, *snap!*

They were brittle and bad. Curses were said, and beers were had.

The next day, today, I went to Autozone to get soft line and connectors to make my own piping so this didn't happen again. After a hour of assembly, the lines came together like a dream and I was finally able to test the new part and see what it would do to the truck.

I literally can not believe it, low and behold it runs WORSE!

Not only does it run even RICHER, the engine isn't keeping a steady idle as it was before, even dying during the first 2 times.

I have no clue what to do now, besides go on with the O2 replacement and new spark plugs, and pray the O2 sensor is just super bad.

I feel like I should mention that I should put on new pigtails, the wires are exposed due to rot, but I have no clue if this would affect it THIS bad.

I will also add that the engine ran this way before I replaced the MAP sensor, so now I am just double lost.

I hear a clicking sound somewhere in the engine bay which sounds to me like a short, but I have no idea where and all of the fuses in the fuse box came back OK.

The only thing I can think of is something related to the EGR, at this point, it has been the only thing I haven't touched.

What are your first thoughts?

-Gideon, Northwest Indiana strong, hopelessly crazy for trains!

"Bluejay"-

1985 F150, 2WD w/ 302W EFI

"The Best Never Rest!"

ArdWrknTrk

Re: "The Great Unscrewing"

Administrator

I think the clicking is the solenoids opening and closing.

Is there a diagnostic in the EVTM?

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

railwayboiii

Re: "The Great Unscrewing"

I'm actually dumb, I kicked off the ignition coil lead to the distributor while working on it!

Put it back on, runs much better, solid idle, but still rich. We'll see what happens post O2.

-Gideon, Northwest Indiana strong, hopelessly crazy for trains!

"Bluejay"-

1985 F150, 2WD w/ 302W EFI

"The Best Never Rest!"

swampedout

Re: "The Great Unscrewing"

Nice looking truck!
Its always frustrating in the beginning but youll work all the little problems out.
Early EFI systems can be confusing but its worth trying to pull codes on it.

Sam
1984 F250. 460. C6. 4x4.
MSD Ignition. Airbag rear suspension
Whole buncha problems

Gary Lewis

Re: "The Great Unscrewing"

Administrator

In reply to this post by railwayboiii

railwayboiii wrote

I'm actually dumb, I kicked off the ignition coil lead to the distributor while working on it!

Put it back on, runs much better, solid idle, but still rich. We'll see what happens post O2.

I think those happenings are meant to keep us humble. Happens to me all the time. Glad you found it!

Gary, AKA "Gary fellow": Profile

railwayboiii

Re: "The Great Unscrewing"

In reply to this post by ArdWrknTrk

THE UNSCREWING CONTINUES! I am not dead!

Significant work was accomplished this week, after a seized O2 sensor and exhaust leak were discovered, new piping, manifolds, a CAT, and new plugs and a O2 sensor were installed. One dang thing after another though!

At first, it sounded good until, the engine's idle just got higher and HIGHER AND HIGHER!!!

I literally have NO clue where to start with this! It isn't even going down!

It never did this before the work was done on it! Any ideas?!

-Gideon, Northwest Indiana strong, hopelessly crazy for trains!

"Bluejay"-

1985 F150, 2WD w/ 302W EFI

"The Best Never Rest!"

ArdWrknTrk

Re: "The Great Unscrewing"

Administrator

Intake leak?
IAC?

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

Gary Lewis

Re: "The Great Unscrewing"

Administrator

Yes, it could be either an intake leak or the idle air controller. But, the fact that it is getting worse, meaning the idle is getting higher, suggests that something is leaking progressively more and more. I wouldn't think an intake leak would do that. But the IAC might. Or a vacuum hose may have cracked and be getting worse? But, it could also be a throttle position sensor.

And let's explain what appears to be going on. The EFI system wants the air/fuel mix to be about 14:1. And, it wants the idle to be ~650 RPM. However, it takes its cue for RPM from the throttle position sensor.

So if the TPS, or the throttle itself, isn't going back to idle then the computer thinks that you want a higher RPM than idle and adjusts the IAC and the fuel injector pulses accordingly.

But if the TPS is going back to idle and yet there's a vacuum leak the computer will add fuel to keep the air/fuel ratio at 14:1, which increases the RPM.

Adjustment of the idle speed is shown on Page 74 here: http://www.garysgaragemahal.com/1985-1986-fuel-system-adjustments.html

Perhaps a better description of adjusting the idle speed is given on Page 168 here: http://www.garysgaragemahal.com/efi-idle-speed-adjustment.html

And a description of the system is given here, although you probably don't need that: http://www.garysgaragemahal.com/efi.html

Gary, AKA "Gary fellow": Profile

85lebaront2

Re: "The Great Unscrewing"

Administrator

Ok, a few items from dealing with my son's 1986 F150 EFI 302. First, the 1985/86 EFI system uses the TPS voltage as the idle set point, not rpm. The set point is pretty sensitive as it is 1.0 VDC +/- .05 VDC. This is critical as the EGR controls start at 1.10 VDC and too much throttle opening will cause a solenoid "chatter" or a surging idle as the EGR opens than closes. The 1987 up systems use a "duty cycle" solenoid rather than the Vacuum/Vent system in 85-86. The wiring harnesses on these were also horrible quality, frayed insulation to the point of shorts and grounds.

I was able to retrieve the harness(s) I had obtained for him and have perfect set of solenoids for the system.

I will not be able really lay these out and do a full inspection/photos until probably 1 June as I am not at home nor will be till Sunday afternoon at the earliest.

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

85lebaront2

Re: "The Great Unscrewing"

Administrator

Ok, did a quick scan of the stuff in the box, it appears there are 2 sets in there. Some damage on each, mostly some missing plug shells.

Bill AKA "LOBO" Profile

railwayboiii

Re: "The Great Unscrewing"

Fun day today. Got codes (fun!)

23- TPS out of range
10- Cylinder balance
(funny story, I was dumb and unplugged the live spark wire from the distributor to see if it was truly dead or not, talk about a shock!)
63- TPS circuit fault
31- EGR valve control fault/EVAP fault
18 Loss of tachometer input, IDM circuit faulure, SPOUT circuit grounded (what the heck is IDM/SPOUT?)

Going to test the TPS and EGR to see if it's in range, but I've been digging up other stories of 86's having the same rough idle and richness issues with the codes.

I thought that the richness issues could be timing, but fiddling with it did little to no good, especially since my timing mark is too far off! I'm pretty sure the balancer has slipped, so it's all by feel now, until I can get it replaced.

I had replaced my TPS sensor the the beginning of the Unscrewing last year. Could a bad ground toast it?

Thank you for your help!

-Gideon, Northwest Indiana strong, hopelessly crazy for trains!

"Bluejay"-

1985 F150, 2WD w/ 302W EFI

"The Best Never Rest!"

ArdWrknTrk

Re: "The Great Unscrewing"

Administrator

One thing about codes.
Always start with the lowest number first.
Often fixing one thing will clear others higher up.

SPOUT is "SPark OUT" it is the computers way of controlling advance.
When setting base timing you always need to remove a jumper (or in very early systems, disconnect the wire)
Your '86 should have a little plug close to the distributor.

The most important ground is the one coming from the main harness directly to the battery - terminal.

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

railwayboiii

Re: "The Great Unscrewing"

Today leaps and bounds have been made. I wasn't able to get my hands on a Motocraft TPS but a Standard one (for 44 dollars I hope it's near the same!)

Installed the new TPS, engine can hold a idle, but still a light surge issue.

Did some testing, engine would nearly die and sputter after coming down from pressing on the pedal.

After this, me and my neighbor readded the Cat and what a difference did it make!

The engine would not die after coming down from high revs except if we floored it!

I'm happy but I'm shocked that the exhaust system being whole had such an effect on it!

In hindsight now, I wonder if the EGR valve is faulty/dirty. Tomorrow, I will do a full cleaning of it.

-Gideon, Northwest Indiana strong, hopelessly crazy for trains!

"Bluejay"-

1985 F150, 2WD w/ 302W EFI

"The Best Never Rest!"

Gary Lewis

Re: "The Great Unscrewing"

Administrator

That's good news! Congrat's! I didn't realize it would make that much difference, but that's good to know.

Gary, AKA "Gary fellow": Profile

85lebaront2

Re: "The Great Unscrewing"

Administrator

Gary, the 1985/86 EFI is a bit different in the way the TPS effects the system. On these the closed throttle voltage is what determines the idle stop setting, starting in 1987 it is a IAC closed rpm and the EEC uses the voltage measured at startup as closed throttle (why it is not good to open the throttle when starting). If the voltage is a bit too high, the EEC will open the EGR vacuum valve and then try to balance things resulting in a surging idle and chattering solenoid valves.

There is a thread Matt posted on FTE on this issue, his was caused by an aftermarket TPS that would not come low enough on the voltage to make the EEC happy.

Bill AKA "LOBO" Profile

Gary Lewis

Re: "The Great Unscrewing"

Administrator

They sure tried some strange stuff before settling on "the right way".

Gary, AKA "Gary fellow": Profile

railwayboiii

Re: "The Great Unscrewing"

It seems as if good deeds do not go unpunished. After doing a full caliper, pad, bearing and rotor installation, it was finally time to bleed the system and take it for the first test drive in months.

Unfortunately, after 3 hours of trying to open the back brake bleeder, we find out that it is VERY rusted. I had the bright idea to try to approach it from the tire side, we took out the tire and drum and found that ALL the springs have rusted off!!!!

The cherry on top, is while working on freeing the screw, the brake line started leaking due to rust!! It's VERY overdue for a brake rebuild.

So now, new hardware and shoes are being ordered and I'm going to sand down the rust off the drums and repaint.

It seems as if my new project this week will be getting a healthy coat of POR-15 in the back (she's flaky)

In addition to this, what diameter of brake line should I get? Any tips?

-Gideon, Northwest Indiana strong, hopelessly crazy for trains!

"Bluejay"-

1985 F150, 2WD w/ 302W EFI

"The Best Never Rest!"

ArdWrknTrk

Re: "The Great Unscrewing"

Administrator

3/16

Replace the hose/splitter/axle vent bolt while you're at it.

Note that the left side brake tube uses a 7/8-20 fitting at the splitter.
If you're not making your own lines be SURE to get the adapter bushing to fit the brass block on the hose.

The above is a public service announcement, from the sponsor of this program....

Jim,
Lil'Red is a '87 F250 HD, 4.10's, 1356 4x4, Zf-5, 3G, PMGR, Saginaw PS, desmogged with a Holley 80508 and Performer intake.
Too much other stuff to mention.

railwayboiii

Re: "The Great Unscrewing"

Thank you!!!

-Gideon, Northwest Indiana strong, hopelessly crazy for trains!

"Bluejay"-

1985 F150, 2WD w/ 302W EFI

"The Best Never Rest!"

1234