Thestiffone
Member
my 1999 expedition will idle like it has been cammed when it gets below 30 degrees. it also will randomly die when i come to a complete stop in drive when it gets below 20 degrees outside help please
Weird Idle Noise
- Thread starter Thestiffone
- Start date
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Lightnig
Full Access Members
Any check engine lights, or other symptoms?
Based on that very brief description, could be a great number of possibilities, but I must admit that a simple misfire comes to mind. that is just a blind guess and shot in the dark without more info...
Based on that very brief description, could be a great number of possibilities, but I must admit that a simple misfire comes to mind. that is just a blind guess and shot in the dark without more info...
1997SCEBFEX
Full Access Members
need more specifics, i.e. when was your last tune, if ever, and what is your
mileage, etc?
If you shift to neutral and apply slight pressure to the accelerator, does it smooth out? Sounds like classic idle air controller. If so, easy to remove and can be cleaned with brake cleaner, then reinstalled, or very inexpensive from most parts stores. it's on the rear of the intake, two bolts and the wiring harness.
have you ever replaced the idle air controller, air cleaner element etc.?
trying to figure it out "blindly" without the who, what, when, where, why, & how is sometimes difficult and want to center in on your issue.
a few IAC pics if that is it.
PanHandler.
mileage, etc?
If you shift to neutral and apply slight pressure to the accelerator, does it smooth out? Sounds like classic idle air controller. If so, easy to remove and can be cleaned with brake cleaner, then reinstalled, or very inexpensive from most parts stores. it's on the rear of the intake, two bolts and the wiring harness.
have you ever replaced the idle air controller, air cleaner element etc.?
trying to figure it out "blindly" without the who, what, when, where, why, & how is sometimes difficult and want to center in on your issue.
a few IAC pics if that is it.
PanHandler.
Attachments
Jcovill125
Member
My 02 5.4 is having the same issue. Check your vacuum lines too. Also check the two black hoses to the right (drivers side) that connect to the EGR thing (can't remember what its called lol) those tend to crack and it will throw a code. Electrical tape works until you can replace them. Basically, check all the hoses for cracks.
Thestiffone
Member
thanks for the help i have not had a tune in a while. But i dont believe it is my IAC for im not throwing any codes and it was replaced about a year and a half ago. my mileage is at 212xxx. the rough idle only happens when its quite cold out. and yes when in neutral it does smooth out. have cleaned my MAF and throttle body with respective cleaners form crc. Although i did have my computer scaned for any problems by a local parts store and my truck did read bank 1 and 2 lean but was informed that it was not enough to casue the problems i was having. also have a K&N air filter.
stamp11127
Full Access Members
Most of the part store employees don't have a clue what they are talking about. Only because they sell parts all day vs. diagnosing and repairing problems.
The engines of today are leaned out already. Now that the O2 sensor has detected a lean condition you should determine the cause and fix it. It may be the problem or contributing to it. The colder air becomes the higher its density = more oxygen = leaner condition.
How many miles since a tune up?
The engines of today are leaned out already. Now that the O2 sensor has detected a lean condition you should determine the cause and fix it. It may be the problem or contributing to it. The colder air becomes the higher its density = more oxygen = leaner condition.
How many miles since a tune up?
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jbanks
Full Access Members
Stamp is right about the part store employees. They don't know everything. Those Lean Codes are telling you something.
Ditch the K&N - Clean the MAF Sensor again
See this thread : http://www.expeditionforum.com/f27/rough-idle-p0171-p0174-heres-what-you-need-check-first-4926/
Just because the IAC was replaced does not mean it's not bad...again...Lot's of times, replacement part quality is hard to determine.
Ditch the K&N - Clean the MAF Sensor again
See this thread : http://www.expeditionforum.com/f27/rough-idle-p0171-p0174-heres-what-you-need-check-first-4926/
Just because the IAC was replaced does not mean it's not bad...again...Lot's of times, replacement part quality is hard to determine.
Not sure if this post will add anything useful, but:
My 2000 5.4l E.B. does something similar. When it is below 20f, when it starts, it runs fine. About the same time the temp gauge gets to about normal (after 5-10 minutes of running), when stopping at a light, it will run fine for about 2-3 seconds, then the Engine Computer wants to go to a different mode, and then the moter will cough and sputter with the rpms going from about 350 to 900 (back and forth quickly). Pressing the gas pedal smooths it right out. I put the scanner on it and have not been able to see what is going on. My scanner unfortunally does not give the IAC count so I cannot see what is going on there. One time it did this I was able to pull off a bank 2 lean pre-code, but it never actually turned on the check engine light.
After about another 5-10 minutes of operation, the issue goes away for good (for that day at least).
I did the vacuum leak check thing. First manually by manipulating all the vacuum hoses, especially the pcv hose where it runs to the back of the intake manifold area. Second by using carb cleaner to check for any engine speed changes while spraying in the likely areas.
My mechanic friend indicates that it could be: 1. the IAC, or 2. a temp sensor that is not working correctly when warming up (i.e. giving the engine computer bad data causing this situation).
The biggest issue is that once the air temp is warm enough for me to want to work the issue, the engine isn't doing it anymore (thus I lose interest in favor of playing some golf).
If you clean the IAC and it helps you, let us know.
My 2000 5.4l E.B. does something similar. When it is below 20f, when it starts, it runs fine. About the same time the temp gauge gets to about normal (after 5-10 minutes of running), when stopping at a light, it will run fine for about 2-3 seconds, then the Engine Computer wants to go to a different mode, and then the moter will cough and sputter with the rpms going from about 350 to 900 (back and forth quickly). Pressing the gas pedal smooths it right out. I put the scanner on it and have not been able to see what is going on. My scanner unfortunally does not give the IAC count so I cannot see what is going on there. One time it did this I was able to pull off a bank 2 lean pre-code, but it never actually turned on the check engine light.
After about another 5-10 minutes of operation, the issue goes away for good (for that day at least).
I did the vacuum leak check thing. First manually by manipulating all the vacuum hoses, especially the pcv hose where it runs to the back of the intake manifold area. Second by using carb cleaner to check for any engine speed changes while spraying in the likely areas.
My mechanic friend indicates that it could be: 1. the IAC, or 2. a temp sensor that is not working correctly when warming up (i.e. giving the engine computer bad data causing this situation).
The biggest issue is that once the air temp is warm enough for me to want to work the issue, the engine isn't doing it anymore (thus I lose interest in favor of playing some golf).
If you clean the IAC and it helps you, let us know.
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Jbanks,
You are correct about some replacement IAC's not being good. I had bought a discount part off the internet and it did not work. Neither did the second one that was sent as a replacement. (these were for a different truck). They both exhibited the same problems, but were different then the original parts failure mode. I then bought a name brand unit from O'Riellys and it worked great.
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Thestiffone
Member
Thanks again. My IAC is a motorcraft new part. And when my IAC originally went out my truck would not idle at all. Also my truck once the outside temp rises to a temperature to work in the problem is gone. Why ditch the k&n filter jbanks
jbanks
Full Access Members
Some oil from the K&N gets sucked in and coats the tiny wires in the MAF sensor and causes inaccuracy. They also do not block as much dirt as a regular filter.
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