Notices
1987 - 1996 F150 & Larger F-Series Trucks 1987 - 1996 Ford F-150, F-250, F-350 and larger pickups - including the 1997 heavy-duty F250/F350+ trucks

Weird???

Old Jan 10, 2008 | 04:11 PM
  #1  
THE KING's Avatar
THE KING
Thread Starter
Joined: Jul 2006
Posts: 1,328
Likes: 0
From: Capac MI
Weird???

Hey guys, Ive been trying to think about how to explain this but its hard to do. So here goes nothing. When im at a stop sign, the truck will be idling good, but the engine will change its pitch to a deep grown. Tac doesnt move and everything seams great. Just weird. Like a deep sound you hear way down in your ears. Its also Irratic. It did it before i took it apart but im just wondering whats causing this? I drove it to college today, bout an 40 miles so 80 miles round trip, city and highway mix, i went through a tad over an eight a tank. Runs really smooth since i put the new cap and rotor on. No more little jolts and an idle. Sometimes i think it stalled it runs so smooth lol.
 
Reply
Old Jan 10, 2008 | 04:14 PM
  #2  
BChance's Avatar
BChance
Elder User
Joined: Apr 2007
Posts: 617
Likes: 0
From: Los Alamos
might just be resonation..hitting just the right frequency to be noticeable..
 
Reply
Old Jan 10, 2008 | 04:16 PM
  #3  
THE KING's Avatar
THE KING
Thread Starter
Joined: Jul 2006
Posts: 1,328
Likes: 0
From: Capac MI
Yea its crazy, Not loud enough to hear when the radio is on, i have a new exhaust and if i point my head towards the rear i can hear the exhaust and doesnt sound like its changing pitch back there, just up by me. Maby its just me lol
 
Reply
Old Jan 10, 2008 | 07:37 PM
  #4  
mhg's Avatar
mhg
Fleet Mechanic
Joined: Sep 2003
Posts: 1,279
Likes: 0
From: savannah,ga
a/c compressor cycling on and off?
 
Reply
Old Jan 10, 2008 | 08:19 PM
  #5  
DJdemon6696's Avatar
DJdemon6696
Posting Guru
Joined: Dec 2006
Posts: 1,923
Likes: 0
mine does it at 600-700 RPMs... when im in a stop light its a loud WOOOOOOOOOOOOOOOOOOOOOOOOOO..... am i right?

if its like that its the exhuast... the flowmaster 40 Delta flow has a DEEP bass rumble to it..
 
Reply
Old Jan 10, 2008 | 08:24 PM
  #6  
THE KING's Avatar
THE KING
Thread Starter
Joined: Jul 2006
Posts: 1,328
Likes: 0
From: Capac MI
Yea thats what mine does, i have no cats and a 40 series its like a WOOOOOOOO WOOOOOOOOO WOOOOOOOOOOOOO WOOOOOOOOOOOO WOOOOOOOOOOOO No rise or drop in the tac at all
 
Reply
Old Jan 10, 2008 | 08:27 PM
  #7  
DJdemon6696's Avatar
DJdemon6696
Posting Guru
Joined: Dec 2006
Posts: 1,923
Likes: 0
yeah mine is a single 3' no cat, flowmaster 40, dump after axle..
jepp its completly normall... i got used to it tough.. maybe it didnt do it before becuase the engine wasnt running as smooth as she is running now..
 
Reply
Old Jan 10, 2008 | 09:20 PM
  #8  
THE KING's Avatar
THE KING
Thread Starter
Joined: Jul 2006
Posts: 1,328
Likes: 0
From: Capac MI
Quite Possible, Its definatly running smooth, i acually got better MPG than my fathers diesel on the highway, I know put a trailer behind them and see who gets the most then lol but im happy. Went from probably going to cost me 25 dollars a day for gas, to 10. Dad and i sat down and figured it out
 
Reply
FTE Stories

Ford Trucks for Ford Truck Enthusiasts

story-0

10 Ugly Ford Trucks That We Still Kinda Love

 Joe Kucinski
story-1

10 Things Every Truck Owner NEEDS (2026 Edition)

 Michael S. Palmer
story-2

Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

 Verdad Gallardo
story-3

Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

 Joe Kucinski
story-4

2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

 Brett Foote
story-5

Top 10 Ford Truck Tragedies

 Joe Kucinski
story-6

AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

 Brett Foote
story-7

Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

 Michael S. Palmer
story-8

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

 Verdad Gallardo
story-9

10 Best Ford Truck Engines We Miss the Most!

 Joe Kucinski
Old Jan 10, 2008 | 09:53 PM
  #9  
DJdemon6696's Avatar
DJdemon6696
Posting Guru
Joined: Dec 2006
Posts: 1,923
Likes: 0
nice... my mpg went up right after i changed the Fuel pressure regulator.. it was 6 mpg's now its at 11 mpg's
i think its the best i will ever see.. or maybe a littlemore after i change my bad ECU
 
Reply
Old Jan 10, 2008 | 09:56 PM
  #10  
THE KING's Avatar
THE KING
Thread Starter
Joined: Jul 2006
Posts: 1,328
Likes: 0
From: Capac MI
Yea, I saw your post about your tires and wheels, They look good! Definatly wish i had the money for those MTZ's Good choice. Lift and tires might be in my near future also. Im getting sick of the low ground clearance lol.
 
Reply
Old Jan 14, 2008 | 09:34 PM
  #11  
Old_Paint's Avatar
Old_Paint
Elder User
Joined: Jun 2006
Posts: 805
Likes: 3
Originally Posted by THE KING
Hey guys, Ive been trying to think about how to explain this but its hard to do. So here goes nothing. When im at a stop sign, the truck will be idling good, but the engine will change its pitch to a deep grown. Tac doesnt move and everything seams great. Just weird. Like a deep sound you hear way down in your ears. Its also Irratic. It did it before i took it apart but im just wondering whats causing this? I drove it to college today, bout an 40 miles so 80 miles round trip, city and highway mix, i went through a tad over an eight a tank. Runs really smooth since i put the new cap and rotor on. No more little jolts and an idle. Sometimes i think it stalled it runs so smooth lol.
Umm, a little hint. Might not be the exhaust at all. There is a heat shield on the bottom of the cab where the cat is/should be/used to be, whatever the case. I put shorties on mine which changed the resonance of the exhaust too, and gave it a decent sound, even with stock Y, cats, and muffler. Then came the VERY annoying buzzing noise. Drove me crazy for a while, now I just ignore it. Turned out to be the heat sheild which is pop-riveted to the bottom of the cab, i.e. no way to tighten it without drilling out the rivets and putting new ones in. The shorties set up a vibration in the exhaust that resonates on the heatsheild. I'll fix it when I build a new true-dual for the Moriah with side dumps.
 
Reply


Thread Tools
Search this Thread

All times are GMT -5. The time now is 06:49 PM.

story-0
10 Ugly Ford Trucks That We Still Kinda Love

Slideshow: 10 ugly Ford trucks that we still kinda love.

By Joe Kucinski | 2026-06-03 09:51:16


VIEW MORE
story-1
10 Things Every Truck Owner NEEDS (2026 Edition)

Slideshow: the best gifts for dads & grads

By Michael S. Palmer | 2026-06-03 15:43:58


VIEW MORE
story-2
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath

Slideshow: Called the Fortress, the 850-horsepower pickup combines Raptor underpinnings with military-inspired features, survival equipment, and a starting price of $285,000.

By Verdad Gallardo | 2026-06-03 11:38:36


VIEW MORE
story-3
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer

Slideshow: 10 most expensive Ford trucks ever sold on Bring a Trailer.

By Joe Kucinski | 2026-05-27 16:24:34


VIEW MORE
story-4
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)

Here's everything that has changed for the latest model year.

By Brett Foote | 2026-05-27 16:17:28


VIEW MORE
story-5
Top 10 Ford Truck Tragedies

Slideshow: Top 10 Ford truck tragedies.

By Joe Kucinski | 2026-05-18 19:34:33


VIEW MORE
story-6
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make

And it might be even better than that.

By Brett Foote | 2026-05-18 19:26:42


VIEW MORE
story-7
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!

Slideshow: Does lowering an F-150 Lobo RUIN the ride quality?

By Michael S. Palmer | 2026-05-18 19:20:37


VIEW MORE
story-8
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-9
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