Idle issues
Thread Starter
|
Trailering
Joined: Feb 2024
Posts: 17
Likes: 5
Idle issues
My 90 F150 5.0 aod trans has developed a high idle when stating cold and settles down if i touch the acc pedal. When i shift from park to drive sometimes the idle will increase and i can hear air flowing somewhere.
Got a code reader and it has checked out with no codes.Drives real good and the aod shifts good also, fuel gauge drops pretty quickly but i don't expect great economy.
The engine has new cap, rotor , plugs and leads. New egr pos sensor and egr solenoid. Not many of these lhd xlt Lariats in Australia.
Thanks in avance for the help.
Got a code reader and it has checked out with no codes.Drives real good and the aod shifts good also, fuel gauge drops pretty quickly but i don't expect great economy.
The engine has new cap, rotor , plugs and leads. New egr pos sensor and egr solenoid. Not many of these lhd xlt Lariats in Australia.
Thanks in avance for the help.
Cargo Master
Joined: Aug 2021
Posts: 2,249
Likes: 738
From: Maryland
Cargo Master
Joined: Aug 2021
Posts: 2,249
Likes: 738
From: Maryland
Hotshot
Joined: Jul 2020
Posts: 10,268
Likes: 2,563
From: Near Salt Lake City
It is supposed to have fdle fast until it warms up
Monitor the ECT voltage (backprobe the sensor)
.64v is hot (hot enough to turn the electric fans on in cars)
1.94v is luke warm and fast idle will result (115 degrees f)
3 volts is a cold engine (room temp)
Your thermostat might be stuck open or broken, not allowing the engine to get up to temp
If you run a quick test it may come back saying something about the engine not being up to temp
Find and buy a super star 2 Ford tester for your powertrain control
Or learn the paperclip method
Get a 1990 PCED and a 1990 EVTM for your truck
Monitor the ECT voltage (backprobe the sensor)
.64v is hot (hot enough to turn the electric fans on in cars)
1.94v is luke warm and fast idle will result (115 degrees f)
3 volts is a cold engine (room temp)
Your thermostat might be stuck open or broken, not allowing the engine to get up to temp
If you run a quick test it may come back saying something about the engine not being up to temp
Find and buy a super star 2 Ford tester for your powertrain control
Or learn the paperclip method
Get a 1990 PCED and a 1990 EVTM for your truck
Cargo Master
Joined: Aug 2021
Posts: 2,249
Likes: 738
From: Maryland
Thread Starter
|
Trailering
Joined: Feb 2024
Posts: 17
Likes: 5
My motorcraft tps arrived and i cleaned up the iac valve again. Fitted the tps and my reading was .81 volts so i elongated the mounting holes and set the tps to .98 and let the computer relearn. The trucks now doesn't have the super high idle and when driving the truck it's really smooth and
responds really well . The aod shifts nice and smooth. Pretty happy with the outcome as is a different truck to drive. My next question is do i replace the 30 year old capacitators in the computer ?
Thanks for the help.
responds really well . The aod shifts nice and smooth. Pretty happy with the outcome as is a different truck to drive. My next question is do i replace the 30 year old capacitators in the computer ?
Thanks for the help.
Trending Topics
Cargo Master
Joined: Aug 2021
Posts: 2,249
Likes: 738
From: Maryland
My motorcraft tps arrived and i cleaned up the iac valve again. Fitted the tps and my reading was .81 volts so i elongated the mounting holes and set the tps to .98 and let the computer relearn. The trucks now doesn't have the super high idle and when driving the truck it's really smooth and
responds really well . The aod shifts nice and smooth. Pretty happy with the outcome as is a different truck to drive. My next question is do i replace the 30 year old capacitators in the computer ?
Thanks for the help.
responds really well . The aod shifts nice and smooth. Pretty happy with the outcome as is a different truck to drive. My next question is do i replace the 30 year old capacitators in the computer ?
Thanks for the help.
As far as capacitors go, if it ain't broke, don't fix it is my motto.
Have you ever pulled engine codes? They'll point you in the right direction, if any are present.
https://www.ford-trucks.com/forums/1...nd-points.html
Here's a thread on ground points. Corroded or loose grounds cause problems.
FTE Stories
Ford Trucks for Ford Truck Enthusiasts
10 Best Ford Truck Engines We Miss the Most!
Joe Kucinski
2026 Shelby F-150 Off-Road: Better Than a Raptor R?
Brett Foote
2027 Super Duty Carhartt Package First Look: 12 Things You NEED to Know!
Michael S. Palmer
10 Most Surprising 2026 Ford Truck Features!
Joe Kucinski
Top 10 Ford Trucks Coming to Mecum Indy 2026
Brett Foote
5 Best / 5 Worst Ford Truck Wheels of All Time
Joe Kucinski
Ford Super Duty: 5 Things Owners LOVE, 5 Things They LOATHE!
Joe Kucinski
Every 2026 Ford Truck Engine RANKED from WORST to FIRST!
Michael S. Palmer
The Best F-150 Deal of Every Trim Level (XL through Raptor)
Joe Kucinski
Thread
Thread Starter
Forum
Replies
Last Post
Moslof77
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
22
Mar 13, 2024 08:52 PM
mrcassidy95
1980 - 1986 Bullnose F100, F150 & Larger F-Series Trucks
5
Jul 6, 2010 10:12 PM
racefan966
1987 - 1996 F150 & Larger F-Series Trucks
11
Nov 14, 2008 09:47 PM