2001 starting issue
Thread Starter
|
Freshman User
Joined: Nov 2006
Posts: 45
Likes: 0
2001 starting issue
Hello all I have a 2001 with the 4.6 liter engine and it has difficulty starting when warm first start of the day is fine evey other start that day it will take longer and I have to hold the gas to the floor to get it to start. It is getting lots of gas. I have put new fuel pump in and completely cleaned out the gas tank as well as new filter and had the injectors replaced new spark plugs and coils. And it runs perfectly fine once running and all speeds not starving issues. Any help would be appriciated.
Lead Driver
Joined: Sep 2006
Posts: 7,907
Likes: 143
Flooring the throttle 'shuts' off the fuel.
Check fuel pressure for being excessive. Should be not more than 40 psi at anytime. Use gage on test port.
Other causes of excess fuel;
#vacuum leak has shifted the fuel tables rich,
#Thermostat stuck open,
#temperature sensor faulty,
intake air control sticks closed. Low hot idle would be the indicator..
.
Use a Scanner to look at these areas # for being out of limits..
Check fuel pressure for being excessive. Should be not more than 40 psi at anytime. Use gage on test port.
Other causes of excess fuel;
#vacuum leak has shifted the fuel tables rich,
#Thermostat stuck open,
#temperature sensor faulty,
intake air control sticks closed. Low hot idle would be the indicator..
.
Use a Scanner to look at these areas # for being out of limits..
Fleet Owner
Joined: Apr 2008
Posts: 24,316
Likes: 5,127
From: 0,0,1
By warm to you mean the weather? Does it start right up in the cool weather?
Hotshot
Joined: Jul 2005
Posts: 11,931
Likes: 180
Bluegrass mentioned temp sensor.... Different animal, but i had an older Explorer that would not start when hot... Looked at everything like you said.... Bluegrass mentioned temp sensor.. and i DID have a code for that but was paying no attention... When the motor is HOT the computer does not " choke" to start... When COLD you need excess gas to start ( think of how an old carburetor car works)...... If your TEMP sensor is not working, the computer can put EXCESS gas into the system because it thinks it is a COLD START UP.................... If you think about it, it makes sense.
Trending Topics
Thread Starter
|
Freshman User
Joined: Nov 2006
Posts: 45
Likes: 0
I had thought of that also but generally when the temp sensor begins to fail it will cause problems idling. But my truck idles perfectly and I did look at the temp sensor PID on my scan tool and it looks fine
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
Lead Driver
Joined: Sep 2006
Posts: 7,907
Likes: 143
It is possible the Crank Sensor plug is dirty and needs re-seating and is temperature sensitive from engine heat.
If this sensor circuit goes open, nothing will work but the fuel pump priming on any ignition On cycle that does not depend on the Crank Sensor for initial pump priming.. This would mean no ignition or fuel injection at cranking.
You have to find the root cause of the issue. Either fuel or ignition first, then pursue that direction.
Are the plugs wet with fuel?
Is ignition missing?
Only difference between cold and hot starting is the temperature of the Cooling system and the Intake air temperature. It's the only way the PCM has to know the difference.
The issue has to be centered on the warm/hot start system signals.
The supporting differences are amount of fuel commanded, ignition timing and IAC opening. The Ox Sensors don't come into the act until they get up to temperature after the motor starts..
If this sensor circuit goes open, nothing will work but the fuel pump priming on any ignition On cycle that does not depend on the Crank Sensor for initial pump priming.. This would mean no ignition or fuel injection at cranking.
You have to find the root cause of the issue. Either fuel or ignition first, then pursue that direction.
Are the plugs wet with fuel?
Is ignition missing?
Only difference between cold and hot starting is the temperature of the Cooling system and the Intake air temperature. It's the only way the PCM has to know the difference.
The issue has to be centered on the warm/hot start system signals.
The supporting differences are amount of fuel commanded, ignition timing and IAC opening. The Ox Sensors don't come into the act until they get up to temperature after the motor starts..
Logistics Pro
Joined: Jan 2001
Posts: 3,740
Likes: 37
From: Central NYS
While you’ Checking stuffs, I’d also check the fuel pressure regulator at the fuel rail. Be sure it vacuum hose is fully connected with no soft spots and that there is no fuel in the vacuum hose.
Thread
Thread Starter
Forum
Replies
Last Post
Odd_Ball
Ford Inline Six, 200, 250, 4.9L / 300
6
Nov 26, 2010 09:41 PM