How would a bad battery affect performance ?
Postmaster
Joined: Jun 2008
Posts: 2,564
Likes: 11
From: Wayyy NoCal, USA
It's unlikely, but possible for an intermittent shorts or opens inside the battery to cause pretty significant voltage fluctuations in the system. The ECU is a computer. Computers don't much like variable voltage. Also, since most sensors are variable resistors, fluctuating input voltages result in fluctuating output voltages - which is what the ECU is "reading" and using to select timing and fuel maps. Think GIGO....
Thread Starter
|
New User
Joined: Mar 2010
Posts: 18
Likes: 0
Just replaced the battery yesterday and started thinking about most everything on these trucks running off of some sort of electricity if it would affect the afore mentioned power, performance .
Trending Topics
Former Vendor
Joined: Sep 2000
Posts: 2,627
Likes: 76
From: South Carolina
my 2 cents
A maf sensor uses voltage to measure air flow (fuel/spark).. when a batteries voltage drops for what ever reason ( weak battery or alt.) say at wide open throttle... the vehicle can drift to a lean condition...
A maf sensor uses voltage to measure air flow (fuel/spark).. when a batteries voltage drops for what ever reason ( weak battery or alt.) say at wide open throttle... the vehicle can drift to a lean condition...
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
10 Fords to Drive Before You Die
Joe Kucinski
3 Best / Worst Features Of The 2025+ Ford Expedition
Brett Foote
10 Ways Ford is LOSING to the Competition
Joe Kucinski
Top 6 Best Deals Available on New Fords & Lincolns Right Now
Brett Foote
This Hennessey Takes the Expedition Tremor's Off-Roading Capability to the Next Level
Verdad Gallardo
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
Thread Starter
|
New User
Joined: Mar 2010
Posts: 18
Likes: 0
So that could be the reason for my drop in fuel mileage ? Maybe we'll see filled up this morning I'll see what I get on this tank?.
FTE Leadership Emeritus
Joined: Jul 2002
Posts: 42,562
Likes: 424
From: Long Island USA
Hmm...
Posting Guru
Joined: Mar 2005
Posts: 2,060
Likes: 7
From: Burnsville, MN
That would depend on how the reference voltage is establish.... Certain devices (like zener diodes) trigger relative to particular set voltages, not as a percentage of the available voltage. Not a clue though as to what is actualy going on inside the PCM....
Thread
Thread Starter
Forum
Replies
Last Post
exidor12
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
5
Sep 13, 2015 06:34 AM
FeralFord
Air Intakes, Air Filters & Ram Air
25
Mar 30, 2012 02:14 PM
cjben
1987 - 1996 F150 & Larger F-Series Trucks
9
Dec 22, 2009 11:53 AM
