Low Idle Issues
Thread Starter
|
Hotshot
Joined: Jun 2003
Posts: 12,343
Likes: 4,369
From: SW VA
Low Idle Issues
I asked this question before...My truck ('97, 4.6L, auto) will bog down to around 450-500 RPM's when coming to a stop, and it will sputter and hesitate when I give it throttle to take off. It doesnt do this every time, but about 80% of the time once the truck is warmed up.
Also, It only does it when in a drive gear. While sitting at a stop light, I can shift into neutral and the RPM's will jump up to 750-800 where they should be. But once I shift back into drive, the RPM's fall back to around 500-600. I can hold the brake and rev the truck towards 1500RPM and let off the throttle slowly, and the RPM's will usually hold 750-800 by the time my foot is off the throttle (also while sitting at a light).
Sometimes, while driving down the road, if I let off the throttle I notice the RPM's drop well below normal, and the truck slows down faster than it should (engine braking).
I just replaced the IAC valve, and it didn't help at all. When I get a chance, I want to clean the MAF....I have no idea if the previous owner ever cleaned/replaced it or not. I've had the truck for 20K miles now (2 years).
Any ideas of what to check for possible solutions?
Also, It only does it when in a drive gear. While sitting at a stop light, I can shift into neutral and the RPM's will jump up to 750-800 where they should be. But once I shift back into drive, the RPM's fall back to around 500-600. I can hold the brake and rev the truck towards 1500RPM and let off the throttle slowly, and the RPM's will usually hold 750-800 by the time my foot is off the throttle (also while sitting at a light).
Sometimes, while driving down the road, if I let off the throttle I notice the RPM's drop well below normal, and the truck slows down faster than it should (engine braking).
I just replaced the IAC valve, and it didn't help at all. When I get a chance, I want to clean the MAF....I have no idea if the previous owner ever cleaned/replaced it or not. I've had the truck for 20K miles now (2 years).
Any ideas of what to check for possible solutions?
Thread Starter
|
Hotshot
Joined: Jun 2003
Posts: 12,343
Likes: 4,369
From: SW VA
I ran seafoam through it not too long ago, but I need to do it again.
I will check the PCV valve when I get a chance. I doubt it has ever been changed (there's 100K on my truck). I just dont want to go replacing what I don't need to...I'm very tight on money. The IAC was $60...
*EDIT*
I forgot to ask...is there a way to check or clean the PCV vavle? I dont want to replace it just yet if I dont have to...
I will check the PCV valve when I get a chance. I doubt it has ever been changed (there's 100K on my truck). I just dont want to go replacing what I don't need to...I'm very tight on money. The IAC was $60...
*EDIT*
I forgot to ask...is there a way to check or clean the PCV vavle? I dont want to replace it just yet if I dont have to...
Freshman User
Joined: Dec 2006
Posts: 25
Likes: 0
Where have you guys been getting your auto parts? I got my IAC valve from Auto Zone and it cost me $42 and my PCV valve was $1.99 at Auto Zone also.I'm not trying to plug them but they were cheaper then anybody including rockauto.com. I dont think you can clean one because once the spring in it is worn out its had it.
Trending Topics
Freshman User
Joined: Dec 2006
Posts: 41
Likes: 0
From: Napoleon Ohio
hey i have 01 5.4L f 150 and i changed everything that they told you to, and i found out that my problem was my tranny... my ford dealer said it was a shutter that gets stuck open or closed when you shift (mine was in second gear mosly) but when it happened it idled about 4-500rpm and vibrated when i accelerated so you might want to look into that too
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
10 Things Every Truck Owner NEEDS (2026 Edition)
Michael S. Palmer
Rezvani's Latest Post-Apocalyptic Monster Is a Ford F-150 Raptor Underneath
Verdad Gallardo
Top 10 Most Expensive Ford Trucks Ever Sold on Bring a Trailer
Joe Kucinski
2027 Ford Super Duty Buyer's Guide (Every Model, Engine, & Package)
Brett Foote
Top 10 Ford Truck Tragedies
Joe Kucinski
AEV FXL Super Duty - the Super Duty Raptor Ford Doesn't Make
Brett Foote
Lobo Vs Lobo: Proof the F-150 Lobo Should Be Even Lower!
Michael S. Palmer
Ford's 2001 Explorer Sportsman Concept Looks For a New Home
Verdad Gallardo
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
Thread Starter
|
Hotshot
Joined: Jun 2003
Posts: 12,343
Likes: 4,369
From: SW VA
Alright...I bought the PCV valve, but havent had time to replace it yet. $3 at AdvanceAuto...I was thinking it was going to be $30-$40...
FYI, I paid $60 at a dealership for the IAC.
BlueWolf: Yes, the spark plugs and wires are all origional. Other than the IAC and the Alternator...everything on the truck is origional (even the rotors).
Thanks for all the information. I should have time tomorrow morning to change it.
FYI, I paid $60 at a dealership for the IAC.
BlueWolf: Yes, the spark plugs and wires are all origional. Other than the IAC and the Alternator...everything on the truck is origional (even the rotors).
Thanks for all the information. I should have time tomorrow morning to change it.
Thread
Thread Starter
Forum
Replies
Last Post
Dennis.King
Escape & Escape Hybrid
0
Feb 8, 2012 09:45 PM
Aune163rd
1987 - 1996 F150 & Larger F-Series Trucks
2
May 8, 2011 02:35 PM