Engine is running rough

Tiny
TERESA BISHOP
  • MEMBER
  • 1997 FORD THUNDERBIRD
  • 4.6L
  • V8
  • RWD
  • AUTOMATIC
  • 275,000 MILES
Car is running rough. We have replaced 02 sensors. Spark plugs. MAF sensor. Cleaned EGR valve. Replaced PCV valve. Checked for vacuum leaks. It has a new fuel pump. What do we need to do next? We reset PCM every time we do something to it. It is about to drive us crazy. Codes p1121, p1131, p0136, p0171, p0174
Saturday, October 14th, 2017 AT 11:33 AM

9 Replies

Tiny
STEVE W.
  • MECHANIC
  • 15,233 POSTS
Check the TPS sensor. If the ECM cannot track it properly it can cause rough running and it would throw other things out as well. STOP disconnecting the battery as well. That resets the idle learn, trans and more.
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Sunday, October 15th, 2017 AT 8:51 PM
Tiny
TERESA BISHOP
  • MEMBER
  • 24 POSTS
Replaced tps sensor and its not better. Its dying when I slow down or come to a stop. It doesn't want to take the gas. And its back firing.
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Sunday, October 22nd, 2017 AT 10:01 AM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,137 POSTS
I would start by doing a compression test to see if we have an engine or not. When the engine misfires it creates lean codes. Can you follow this guide and get back to us?

https://www.2carpros.com/articles/how-to-test-engine-compression

and

https://www.2carpros.com/articles/symptoms-of-low-compression

and

https://www.2carpros.com/articles/the-reasons-for-low-compression

Cheers, Ken

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Monday, October 23rd, 2017 AT 2:25 PM
Tiny
STEVE W.
  • MECHANIC
  • 15,233 POSTS
Dying when slowing or idling is a symptom of a dirty idle air control and losing it's idle control.
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Monday, October 23rd, 2017 AT 3:17 PM
Tiny
TERESA BISHOP
  • MEMBER
  • 24 POSTS
If the compression was bad wouldn't it run bad constantly?
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Monday, October 23rd, 2017 AT 3:59 PM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,137 POSTS
Yes it would, can you shoot a quick video of how it is running so we can see? Upload it here from your phone.
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Tuesday, October 24th, 2017 AT 11:56 AM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,137 POSTS
Anything on this problem?
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Wednesday, October 25th, 2017 AT 2:10 PM
Tiny
TERESA BISHOP
  • MEMBER
  • 24 POSTS
My husband did a vacuum test and he came to the conclusion its a clogged converter. He said there's no way to get it off. The way the tbird is made you can't hardly get to anything. Any suggestions?
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Thursday, October 26th, 2017 AT 4:04 AM
Tiny
KEN L
  • MASTER CERTIFIED MECHANIC
  • 54,137 POSTS
Those are a tough on but it can be replaced, Here is a guide that will give you an idea of what to do to fix the problem.

https://www.2carpros.com/articles/catalytic-converter-replacement

You will need to raise the car up safely,

https://www.2carpros.com/articles/jack-up-and-lift-your-car-safely

Here is what it will be like for your car (below)

Please let us know what happens.

Cheers, Ken
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Friday, October 27th, 2017 AT 11:17 AM

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