Notices
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks Discuss the Early Eighties Bullnose Ford Truck

LT Headers/o2 sensor problems

Thread Tools
 
Search this Thread
 
Old Dec 26, 2008 | 08:54 PM
  #1  
EffunFiddy's Avatar
EffunFiddy
Thread Starter
|
Senior User
Joined: Jun 2008
Posts: 352
Likes: 2
From: Lucknow, ON
LT Headers/o2 sensor problems

Hey,
I have an 85 f150 2WD with 5.0L EFI and long tube headers with true duals. I relocated the o2 sensor to roughly the same spot as factory but it was only in the no.4 cylinder tube on the header. The sensor is brand new and whenever i start the truck and run it to temperature it begins smoking only out of the passenger side, the same side as the sensor. I was wondering if i need to locate it to the collector to get a proper reading? I have to removie the headers anyways to sandblast and repaint them because there was rust under the crappy-*** factory paint causing the paint to all flake when i first started it lol. To relocate to the collector i need a sensor extension for the wire to reach and all i can find are ones for 86 mustangs in a set of two since the mustangs have two sensors. I was wondering if the extensions would be the same for mustangs as the f150s? Any help would be greatly appreciated, thanks.
 
Reply
Old Dec 26, 2008 | 09:13 PM
  #2  
uncle.stosh's Avatar
uncle.stosh
Postmaster
Joined: Feb 2008
Posts: 2,658
Likes: 5
From: Out of here
I can't help you with the wiring, but to answer your first question:

Yes, the O2 sensor should always be in the collector. That way you are sampling the entire bank, not just one cylinder.
 
Reply
Old Dec 26, 2008 | 10:06 PM
  #3  
EffunFiddy's Avatar
EffunFiddy
Thread Starter
|
Senior User
Joined: Jun 2008
Posts: 352
Likes: 2
From: Lucknow, ON
Thanks very much uncle.stosh. Would the current o2 sensor location in the 4th cylinder tube be causing the engine to smoke out of that one side?
P.S. I notcied you're a flareside fan, my truck is also a flareside. I love 'em.
Thanks again
 
Reply
Old Dec 27, 2008 | 06:28 PM
  #4  
Franklin2's Avatar
Franklin2
Moderator
25 Year Member
Photogenic
Community Builder
Community Influencer
Joined: Jan 2001
Posts: 56,950
Likes: 2,718
From: Virginia
Club FTE Gold Member
If the number 4 cylinder was running lean for some reason, the O2 sensor would tell the computer this, and the computer would make the whole engine rich. The smoke you are seeing. Is it black?

Some guys who are messing with their FI engines are just leaving the o2 sensor disconnected. This puts the computer in the open loop mode, where it doesn't look at the O2 sensor for fueling instructions, but instead looks up fueling in tables in the memory of the computer. Your fuel mileage may suffer some if you do this, but you never know till you try it.
 
Reply
Old Dec 27, 2008 | 09:07 PM
  #5  
EffunFiddy's Avatar
EffunFiddy
Thread Starter
|
Senior User
Joined: Jun 2008
Posts: 352
Likes: 2
From: Lucknow, ON
Oh yeah, the smoke was black. It's alot of fuel not getting burned. If it's not the o2 sensor, then I figure it's more than likely a bad plug or two or a bad wire or two. If it's either, they are all getting replaced regardless. The timing isn't exactly spot on either, all of which could i suppose make a difference. I suppose i should try all of these things first and then see what happens. The plugs were old and a little blackened from a vaccum line that was off, which we fixed and the wires, as far as I can see are original. Wouldn't be surprised if it could also use a new cap and rotor too. I'll be replacing all the wires, plugs, cap and rotor with likely some performance ones just for ****s 'n giggles. Just wondering if anybody had heard of this happening before because it's only smoking out of the one side and the whole truck was more or less tore completely apart over the course of last winter and something could have possibly gone wrong in that time, although i hope not. Thanks again for the help guys.
 
Reply




All times are GMT -5. The time now is 11:19 AM.

story-0
Ford's 2001 Explorer Sportsman Concept Looks For a New Home

Slideshow: Ford's bizarre fishing-themed Explorer concept has resurfaced after spending decades largely forgotten.

By Verdad Gallardo | 2026-05-12 18:07:46


VIEW MORE
story-1
10 Best Ford Truck Engines We Miss the Most!

Slideshow: The 10 best Ford truck engines we miss the most.

By Joe Kucinski | 2026-05-12 13:09:47


VIEW MORE
story-2
2026 Shelby F-150 Off-Road: Better Than a Raptor R?

Slideshow: first look at the 810 hp 2026 Shelby F-150 Off-Road!

By Brett Foote | 2026-05-12 12:50:07


VIEW MORE
story-3
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!

Slideshow: Everything You Need to Know about the 2027 Super Duty Carhartt Package!

By Michael S. Palmer | 2026-05-07 17:51:06


VIEW MORE
story-4
10 Most Surprising 2026 Ford Truck Features!

Slideshow: 10 most surprising Ford truck options/features in 2026.

By Joe Kucinski | 2026-05-05 11:17:22


VIEW MORE
story-5
Top 10 Ford Trucks Coming to Mecum Indy 2026

Slideshow: Here are the top 10 Fords coming to Mecum Indy 2026.

By Brett Foote | 2026-05-04 13:49:49


VIEW MORE
story-6
5 Best / 5 Worst Ford Truck Wheels of All Time

Slideshow: The 5 best and 5 worst Ford truck wheels of all time

By Joe Kucinski | 2026-04-29 16:49:01


VIEW MORE
story-7
Ford Super Duty: 5 Things Owners LOVE, 5 Things They LOATHE!

Slideshow: Ranking the 5 things owners love about their Super Duty and 5 things they don't

By Joe Kucinski | 2026-04-29 16:36:49


VIEW MORE
story-8
Every 2026 Ford Truck Engine RANKED from WORST to FIRST!

Slideshow: Ranking all 12 Ford truck engines available in 2026.

By Michael S. Palmer | 2026-04-22 13:32:20


VIEW MORE
story-9
The Best F-150 Deal of Every Trim Level (XL through Raptor)

Slideshow: The best Ford F-150 deal for every trim level (XL through Raptor)

By Joe Kucinski | 2026-04-21 15:59:01


VIEW MORE