4.9 sputtering and idk why - Ford F150 Forum - Community of Ford Truck Fans

Topic Sponsor
1987 - 1996 F150 Still running strong! Talk about your 8th and 9th generation Ford F150 trucks.

4.9 sputtering and idk why

Reply

 
 
 
Old 07-20-2010, 09:40 PM
  #1  
Senior Member
Thread Starter
 
91whitelariat's Avatar
 
Join Date: Jan 2010
Location: Gray, GA
Posts: 113
Thanks: 0
Thanked 0 Times in 0 Posts
Default 4.9 sputtering and idk why

I got a 91 4.9 and it has a weird skip/sputtering, its not on a regular cycle like one cylinder, it just does it when it feels like it. What is this? I ran seafoam through it and got a k&n drop in lately too...Just saying. Any help is appreciated. Thanks.
91whitelariat is offline  
Reply With Quote
Old 07-21-2010, 07:31 AM
  #2  
Senior Member
 
Pine Barron's Avatar
 
Join Date: May 2009
Location: NJ
Posts: 171
Thanks: 0
Thanked 2 Times in 2 Posts
Default

How long has it been since you your air filter, spark plugs, plugwires, were replaced? If it is truely random you might also want to check your ground connection.

After that i think anybody here would tell you the next step in isolating the problem would be to check for error codes. The steps for doing that are here https://www.f150forum.com/f10/how-re...es-obdi-10907/

Good luck.
Pine Barron is offline  
Reply With Quote
Old 07-21-2010, 09:26 AM
  #3  
I NOM NOM NOM Threads...
 
Franchi's Avatar
 
Join Date: Sep 2008
Location: Wal-Mart, Women's section.
Posts: 5,751
Thanks: 0
Thanked 8 Times in 5 Posts
Default

Is it jerking/shuddering when under accleration? Could be a pinhole in a vacuum line as well. But I'd check Pine's suggestion first.
Franchi is offline  
Reply With Quote
Old 07-21-2010, 08:22 PM
  #4  
Junior Member
 
Join Date: Jun 2010
Posts: 14
Thanks: 0
Thanked 0 Times in 0 Posts
Default

it could be a number of things. first thing to check is the spark plugs and replace plugs, wires and distributer cap all at once if they seem worn out. if it still persists next i would check is 02 sensor. if its over 80grand on the odometer since the last one its a good idea to replace it. it would throw an engine if it was bad though... other than that check vaccuum lines(especially if ur cruise control doesnt work it would point to this since cruise works off vaccuum lines) after that i would say check for faulty gaskets in the throttle body/upper plenum/ intake manifold, or else maybe even could be a bad cat or two. after that the only thing i could think of is a fuel pump going bad or just plain old bad delivery. if theres a code it would be hella easier though to pinpoint whats wrong.
jd whitney is offline  
Reply With Quote
Old 07-22-2010, 09:35 AM
  #5  
Senior Member
Thread Starter
 
91whitelariat's Avatar
 
Join Date: Jan 2010
Location: Gray, GA
Posts: 113
Thanks: 0
Thanked 0 Times in 0 Posts
Default

ok Well i will go ahead and say that plugs and dist cap are fairly new but idk about wires, just got a new air filter, and i think vacuum lines are good, cruise control works. I will check codes soon, i have checked it before and posted the codes i got but nobody really helped. I will see if i can check for codes again.
91whitelariat is offline  
Reply With Quote
Old 08-19-2010, 04:25 AM
  #6  
Junior Member
 
Join Date: Aug 2010
Posts: 20
Thanks: 0
Thanked 0 Times in 0 Posts
Default

i have a 1992 i had a idol problem solved it myself with throttle body cleaning front and backside cleaned with carb cleaner and small wire brush removed 18 years of junk was a mess no more eratic odol etc. runs super now .. good luck
sam2007 is offline  
Reply With Quote
Old 08-20-2010, 10:36 PM
  #7  
Senior Member
 
GMtraitor's Avatar
 
Join Date: Aug 2010
Location: WV
Posts: 104
Thanks: 0
Thanked 5 Times in 4 Posts
Default

Originally Posted by jd whitney View Post
it could be a number of things. first thing to check is the spark plugs and replace plugs, wires and distributer cap all at once if they seem worn out. if it still persists next i would check is 02 sensor. if its over 80grand on the odometer since the last one its a good idea to replace it. it would throw an engine if it was bad though... other than that check vaccuum lines(especially if ur cruise control doesnt work it would point to this since cruise works off vaccuum lines) after that i would say check for faulty gaskets in the throttle body/upper plenum/ intake manifold, or else maybe even could be a bad cat or two. after that the only thing i could think of is a fuel pump going bad or just plain old bad delivery. if theres a code it would be hella easier though to pinpoint whats wrong.
I would do these steps exactly in order!!! Definately spark or sensor (probably o2) try to check for codes before u start checking around for leaky gaskets and fuel pump
GMtraitor is offline  
Reply With Quote
 
 
 


Thread Tools
Search this Thread
Quick Reply: 4.9 sputtering and idk why


Contact Us Advertising Cookie Policy Privacy Statement Terms of Service

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.
 
  • Ask a Question
    Get answers from community experts
Question Title:
Description:
Your question will be posted in: