Not idling?

1999 FORD EXPEDITION
250,000 MILES • 5.4L • V8 • 4WD • AUTOMATIC
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DIANA WALLACE
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  • 4 POSTS
Okay, thought the problem was the fuel filter and replaced it. Then vacuum lines were messed with and it won't idle from that point. I replaced catalytic converters and o2 sensors just yesterday and replaced them with a used ERG valve. Still won't idle.
I'm stumped!!!!
Dec 7, 2022 at 1:57 PM
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JACOBANDNICKOLAS
  • AUTOMOTIVE REPAIR CONTRIBUTOR
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Diana,

If someone was messing with the vacuum hoses, that is what is likely causing this issue. Chances are one of the hoses is damaged, cracked, disconnected, or installed incorrectly.

Do me a favor. Take a look at this link. It explains how to check for, locate, and repair an engine vacuum leak. Let me know if this is something you are comfortable performing.

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Also, from the rear of the throttle body, there is a vacuum hose that has a 90-degree angle in it. The angle is known to dry rot and leak.

Let me know what you find, what I can do to help, or if you simply have other questions.,

Take care,

Joe
Dec 7, 2022 at 6:30 PM
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DIANA WALLACE
  • MEMBER
  • 4 POSTS
Thanks for the suggestions!
Okay, I tried all that and can't find any issues with the vacuum lines.
Did inspect the throttle body and that's all gummed up and when that was disconnected from the lines, it idled on its own, but that was short lived. I also took off the main vacuum line and it was too gummed up and it stayed idling, great sign!! So going to clean the heck out of both and hopefully that'll help.
It's still at a consistent idle running rough.
Any suggestions are welcome and appreciated!!
We are getting closer it seems!
Dec 10, 2022 at 10:10 AM
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JACOBANDNICKOLAS
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 110,190 POSTS
Hi,

Is it the hoses that are gummed up or the throttle body? As far as the throttle body, here is a link you may find helpful:

https://www.2carpros.com/articles/throttle-actuator-service

Let me know if that helps and how things turn out for you.

Take care,

Joe

Dec 10, 2022 at 6:15 PM
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DIANA WALLACE
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  • 4 POSTS
Hey Joe,

It's fixed!! Finally!
It was a vacuum line that was near the firewall in the back of the engine. It is now idling and running great!! What a pain in the butt that was to find.
Thanks for the help!
Dec 11, 2022 at 9:07 AM
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JACOBANDNICKOLAS
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 110,190 POSTS
Hi,

Excellent! I'm glad you found it. They can be a pain. LOL Just out of curiosity, was it a hose that has a 90-degree bend in it? I've seen that one off the rear of the engine dry rot and leak.

Regardless, if you have a chance, let me know. Also, thanks for the update, and feel free to come back in the future. You're always welcome.

Take care,

Joe
Dec 11, 2022 at 12:54 PM
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DIANA WALLACE
  • MEMBER
  • 4 POSTS
Hey,

It was an angle part but had two lines going into it. And it was dry rotted like no other. My brother-in-law actually found it. He was literally laying on the engine and his arms were deep down behind it. Went to the parts house and it was a $25.00 fix!!
I'm just elated it's running right again.
Happy dance!!
Thanks again Joe!!!
Dec 11, 2022 at 1:16 PM
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JACOBANDNICKOLAS
  • AUTOMOTIVE REPAIR CONTRIBUTOR
  • 110,190 POSTS
Hi,

You are very welcome. I wish I had a nickel for each time that hose has caused an issue.

Regardless, thanks for letting me know. Also, feel free to come back anytime in the future. You are always welcome here.

Take care and I hope you have a great Christmas.

Joe
Dec 11, 2022 at 6:22 PM