General Technical & Electrical General technical and electrical discussion for the Ford Ranger that does not fit in any other sub-forum.

1990 4.0

Thread Tools
 
Search this Thread
 
Old Feb 29, 2016
  #1  
fayjim2's Avatar
Thread Starter
|
Member
Joined: Apr 2011
Posts: 12
Likes: 0
From: Athol Id.
1990 4.0

My 1990 4.0 just won,t idle smooth,in fact at times I need to shift to neutral . I posted this before and I don,t like buying parts shotgun style. This does it sometines when its cold and then it may do it when warm? Help out a old mAN. FAYJIM2@FRONTIER.COM thanks
 
Reply
Old Feb 29, 2016
  #2  
RonD's Avatar
RF Veteran
iTrader: (1)
Joined: Jan 2014
Posts: 30,635
Likes: 2,952
From: Vancouver, BC
IAC(idle air control) Valve is how computer sets warm and cold idle RPMs.
It should be cleaned every 5 years or so.
Just 2 bolts.

read here for details: How to: IAC valve cleaning thread (w/pics) - Ford Explorer and Ranger Forums "Serious Explorations"®


4.0l OHV engines eat most brands of spark plugs, Motorcraft seem to last the longest, then Autolite.
Never use single platinum spark plugs on distributorless Fords, regular or double platinum only, single is a waste of money.

Worn out spark plugs cause rough idles.

My '94 spark plug wires lasted 18 years, but they did eventually start to cause misfires, poor idle.
 
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
reader585
Project Logs
14
Dec 8, 2008 04:18 PM
BigDSnyder
General Ford Ranger Discussion
9
Jul 16, 2007 05:30 AM
reelfishin
General Ford Ranger Discussion
8
Oct 27, 2006 12:50 AM
opivyattack
Auto Detailing 101
11
Oct 19, 2006 06:55 AM
Hoover
Suspension Tech
5
Aug 26, 2005 06:00 PM




All times are GMT -6. The time now is 09:16 AM.